Applications & Pathways
Preference Structure on the Design of Hydrogen Refueling Stations to Activate Energy Transition
Aug 2020
Publication
As a countermeasure to the greenhouse gas problem the world is focusing on alternative fuel vehicles (AFVs). The most prominent alternatives are battery electric vehicles (BEV) and fuel cell electric vehicles (FCEVs). This study examines FCEVs especially considering hydrogen refueling stations to fill the gap in the research. Many studies suggest the important impact that infrastructure has on the diffusion of AFVs but they do not provide quantitative preferences for the design of hydrogen refueling stations. This study analyzes and presents a consumer preference structure for hydrogen refueling stations considering the production method distance probability of failure to refuel number of dispensers and fuel costs as core attributes. For the analysis stated preference data are applied to choice experiments and mixed logit is used for the estimation. Results indicate that the supply stability of hydrogen refueling stations is the second most important attribute following fuel price. Consumers are willing to pay more for green hydrogen compared to gray hydrogen which is hydrogen produced by fossil fuels. Driver fuel type and perception of hydrogen energy influence structure preference. Our results suggest a specific design for hydrogen refueling stations based on the characteristics of user groups.
A Combined Heat and Green Hydrogen (CHH) Generator Integrated with a Heat Network
Sep 2021
Publication
Combined heat and power (CHP) systems offer high energy efficiencies as they utilise both the electricity generated and any excess heat by co-suppling to local consumers. This work presents the potential of a combined heat and hydrogen (CHH) system a solution where Proton exchange membrane (PEM) electrolysis systems producing hydrogen at 60–70% efficiency also co-supply the excess heat to local heat networks. This work investigates the method of capture and utilisation of the excess heat from electrolysis. The analysed system was able to capture 312 kW of thermal energy per MW of electricity and can deliver it as heated water at either 75 ◦C or 45 ◦C this appropriate for existing district heat networks and lower temperature heat networks respectively. This yields an overall CHH system efficiency of 94.6%. An economic analysis was conducted based on income generated through revenue sales of both hydrogen and heat which resulted in a significant reduction in the Levelized Cost of Hydrogen.
Hydrogen to Support Electricity Systems
Jan 2020
Publication
The Department of Environment Land Water and Planning (DELWP) engaged GHD Advisory and ACIL Allen to assess the roles opportunities and challenges that hydrogen might play in the future to support Australia’s power systems and to determine whether the relevant electricity system regulatory frameworks are compatible with both enabling an industrial-scale1 hydrogen production capability and the use of hydrogen for power generation.
You can read the full report on the website of the Australian Government at this link
You can read the full report on the website of the Australian Government at this link
Experimental Investigation of the Effect of Hydrogen Addition on Combustion Performance and Emissions Characteristics of a Spark Ignition High Speed Gasoline Engine
Sep 2014
Publication
Considering energy crises and pollution problems today much work has been done for alternative fuels for fossil fuels and lowering the toxic components in the combustion products. Expert studies proved that hydrogen one of the prominent alternative energy source which has many excellent combustion properties that can be used for improving combustion and emissions performance of gasoline-fuelled spark ignition (SI) engines. This article experimentally investigated the performance and emission characteristics of a high speed single cylinder SI engine operating with different hydrogen gasoline blends. For this purpose the conventional carburetted high speed SI engine was modified into an electronically controllable engine with help of electronic control unit (ECU) which dedicatedly used to control the injection timings and injection durations of gasoline. Various hydrogen enrichment levels were selected to investigate the effect of hydrogen addition on engine brake mean effective pressure (Bmep) brake thermal efficiency volumetric efficiency and emission characteristics. The test results demonstrated that combustion performances fuel consumption and brake mean effective pressure were eased with hydrogen enrichment. The experimental results also showed that the brake thermal efficiency was higher than that for the pure gasoline operation. Moreover HC and CO emissions were all reduced after hydrogen enrichment.
The Technical and Economic Potential of the H2@Scale Concept within the United States
Oct 2020
Publication
The U.S. energy system is evolving as society and technologies change. Renewable electricity generation—especially from wind and solar—is growing rapidly and alternative energy sources are being developed and implemented across the residential commercial transportation and industrial sectors to take advantage of their cost security and health benefits. Systemic changes present numerous challenges to grid resiliency and energy affordability creating a need for synergistic solutions that satisfy multiple applications while yielding system-wide cost and emissions benefits. One such solution is an integrated hydrogen energy system (Figure ES-1). This is the focus of H2@Scale—a U.S. Department of Energy (DOE) initiative led by the Office of Energy Efficiency and Renewable Energy’s Hydrogen and Fuel Technologies Office. H2@Scale brings together stakeholders to advance affordable hydrogen production transport storage and utilization in multiple energy sectors. The H2@Scale concept involves hydrogen as an energy intermediate. Hydrogen can be produced from various conventional and renewable energy sources including as a responsive load on the electric grid. Hydrogen has many current applications and many more potential applications such as energy for transportation—used directly in fuel cell electric vehicles (FCEVs) as a feedstock for synthetic fuels and to upgrade oil and biomass—feedstock for industry (e.g. for ammonia production metals refining and other end uses) heat for industry and buildings and electricity storage. Owing to its flexibility and fungibility a hydrogen intermediate could link energy sources that have surplus availability to markets that require energy or chemical feedstocks benefiting both. This document builds upon a growing body of analyses of hydrogen as an energy intermediate by reporting the results from our initial analysis of the potential impacts of the H2@Scale vision by the mid-21st century for the 48 contiguous U.S. states. Previous estimates have been based on expert elicitation and focused on hydrogen demands. We build upon them first by estimating hydrogen’s serviceable consumption potential for possible hydrogen applications and the technical potential for producing hydrogen from various resources. We define the serviceable consumption potential as the quantity of hydrogen that would be consumed to serve the portion of the market that could be captured without considering economics (i.e. if the price of hydrogen were $0/kg over an extended period); thus it can be considered an upper bound for the size of the market. We define the technical potential as the resource potential constrained by real-world geography and system performance but not by economics. We then compare the cumulative serviceable consumption potential with the technical potential of a number of possible sources. Second we estimate economic potential: the quantity of hydrogen at an equilibrium price at which suppliers are willing to sell and consumers are willing to buy the same quantity of hydrogen. We believe this method provides a deeper understanding than was available in the previous analyses. We develop economic potentials for multiple scenarios across various market and technology-advancement assumptions.
An Overview of Promising Alternative Fuels for Road, Rail, Air, and Inland Waterway Transport in Germany
Feb 2022
Publication
To solve the challenge of decarbonizing the transport sector a broad variety of alternative fuels based on different concepts including Power-to-Gas and Power-to-Liquid and propulsion systems have been developed. The current research landscape is investigating either a selection of fuel options or a selection of criteria a comprehensive overview is missing so far. This study aims to close this gap by providing a holistic analysis of existing fuel and drivetrain options spanning production to utilization. For this purpose a case study for Germany is performed considering different vehicle classes in road rail inland waterway and air transport. The evaluated criteria on the production side include technical maturity costs as well as environmental impacts whereas on the utilization side possible blending with existing fossil fuels and the satisfaction of the required mission ranges are evaluated. Overall the fuels and propulsion systems Methanol-to-Gasoline Fischer–Tropsch diesel and kerosene hydrogen battery-electric propulsion HVO DME and natural gas are identified as promising future options. All of these promising fuels could reach near-zero greenhouse gas emissions bounded to some mandatory preconditions. However the current research landscape is characterized by high insecurity with regard to fuel costs depending on the predicted range and length of value chains.
Hybrid Hydrogen PEM Fuel Cell and Batteries Without DC–DC Converter
Sep 2013
Publication
Concerns about greenhouse gases as well as the price and security of oil supply have acted as a spur to sustainable automobile development. The hydrogen fuel cells electric vehicle (HFCEV) is generally recognised by leading automobile manufacturers and scientists as one of the optimum technologies for long-term future low carbon vehicle. In a typical HFCEV power train a DC–DC converter is required to balance the voltage difference between the fuel cells (FCs) stack and batteries. However research shows that a considerable amount of energy generated by the hydrogen FCs stack is deplete during this conversion process as heat. This experiment aims to improve the power train efficiency by eliminating the DC–DC converter by finding the best combination of FC stack and batteries matching the size and capacity of the electrical components.
Hydrogen Double Compression-expansion Engine (H2DCEE): A Sustainable Internal Combustion Engine with 60%+ Brake Thermal Efficiency Potential at 45 Bar BMEP
May 2022
Publication
Hydrogen (H2) internal combustion engines may represent cost-effective and quick solution to the issue of the road transport decarbonization. A major factor limiting their competitiveness relative to fuel cells (FC) is the lower efficiency. The present work aims to demonstrate the feasibility of a H2 engine with FC-like 60%+ brake thermal efficiency (BTE) levels using a double compression-expansion engine (DCEE) concept combined with a high pressure direct injection (HPDI) nonpremixed H2 combustion. Experimentally validated 3D CFD simulations are combined with 1D GT-Power simulations to make the predictions. Several modifications to the system design and operating conditions are systematically implemented and their effects are investigated. Addition of a catalytic burner in the combustor exhaust insulation of the expander dehumidification of the EGR and removal of the intercooling yielded 1.5 1.3 0.8 and 0.5%-point BTE improvements respectively. Raising the peak pressure to 300 bar via a larger compressor further improved the BTE by 1.8%-points but should be accompanied with a higher injector-cylinder differential pressure. The λ of ~1.4 gave the optimum tradeoff between the mechanical and combustion efficiencies. A peak BTE of 60.3% is reported with H2DCEE which is ~5%-points higher than the best diesel-fueled DCEE alternative.
Strategies for the Sampling of Hydrogen at Refuelling Stations for Purity Assessment
Aug 2021
Publication
Hydrogen delivered at hydrogen refuelling station must be compliant with requirements stated in different standards which require specialized sampling device and personnel to operate it. Currently different strategies are implemented in different parts of the world and these strategies have already been used to perform 100s of hydrogen fuel sampling in USA EU and Japan. However these strategies have never been compared on a large systematic study. The purpose of this paper is to describe and compare the different strategies for sampling hydrogen at the nozzle and summarize the key aspects of all the existing hydrogen fuel sampling including discussion on material compatibility with the impurities that must be assessed. This review highlights the fact it is currently difficult to evaluate the impact or the difference these strategies would have on the hydrogen fuel quality assessment. Therefore comparative sampling studies are required to evaluate the equivalence between the different sampling strategies. This is the first step to support the standardization of hydrogen fuel sampling and to identify future research and development area for hydrogen fuel sampling.
The Sector Coupling Concept: A Critical Review
Jun 2020
Publication
Pursued climate goals require reduced greenhouse gas emissions by substituting fossil fuels with energy from renewable sources in all energy-consuming processes. On a large-scale this can mainly be achieved through electricity from wind and sun which are subject to intermittency. To efficiently integrate this variable energy a coupling of the power sector to the residential transport industry and commercial/trade sector is often promoted called sector coupling (SC). Nevertheless our literature review indicates that SC is frequently misinterpreted and its scope varies among available research from exclusively considering the use of excess renewable electricity to a rather holistic view of integrated energy systems including excess heat or even biomass sources. The core objective of this article is to provide a thorough understanding of the SC concept through an analysis of its origin and its main purpose as described in the current literature. We provide a structured categorization of SC derived from our findings and critically discuss its remaining challenges as well as its value for renewable energy systems. We find that SC is rooted in the increasing use of variable renewable energy sources and its main assets are the flexibility it provides for renewable energy systems decarbonization potential for fossil-fuel-based end-consumption sectors and consequently reduced dependency on oil and gas extracting countries. However the enabling technologies face great challenges in their economic feasibility because of the uncertain future development of competing solutions.
Refuelling Infrastructure Requirements for Renewable Hydrogen Road Fuel through the Energy Transition
Nov 2022
Publication
Current commercially available options for decarbonisation of road transport are battery electric vehicles or hydrogen fuel cell electric vehicles. BEVs are increasingly deployed while hydrogen is in its infancy. We examine the infrastructure necessary to support hydrogen fuelling to various degrees of market penetration. Scotland makes a good exemplar of transport transition with a world leading Net-Zero ambition and proven pathways for generating ample renewable energy. We identified essential elements of the new transport systems and the associated capital expenditure. We developed nine scenarios based on the pace of change and the ultimate market share of hydrogen and constructed a model to analyse their infrastructure requirements. This is a multi-period model incorporating Monte Carlo and Markov Chain elements. A “no-regrets” initial action is rapid deployment of enough hydrogen infrastructure to facilitate the early years of a scenario where diesel fuel becomes replaced with hydrogen. Even in a lower demand scenario of only large and heavy goods vehicles using hydrogen the same infrastructure would be required within a further two years. Subsequent investment in infrastructure could be considered in the light of this initial development.
Comparative Study of Spark-Ignited and Pre-Chamber Hydrogen-Fueled Engine: A Computational Approach
Nov 2022
Publication
Hydrogen is a promising future fuel to enable the transition of transportation sector toward carbon neutrality. The direct utilization of H2 in internal combustion engines (ICEs) faces three major challenges: high NOx emissions severe pressure rise rates and pre-ignition at mid to high loads. In this study the potential of H2 combustion in a truck-size engine operated in spark ignition (SI) and pre-chamber (PC) mode was investigated. To mitigate the high pressure rise rate with the SI configuration the effects of three primary parameters on the engine combustion performance and NOx emissions were evaluated including the compression ratio (CR) the air–fuel ratio and the spark timing. In the simulations the severity of the pressure rise was evaluated based on the maximum pressure rise rate (MPRR). Lower compression ratios were assessed as a means to mitigate the auto-ignition while enabling a wider range of engine operation. The study showed that by lowering CR from 16.5:1 to 12.5:1 an indicated thermal efficiency of 47.5% can be achieved at 9.4 bar indicated mean effective pressure (IMEP) conditions. Aiming to restrain the auto-ignition while maintaining good efficiency growth in λ was examined under different CRs. The simulated data suggested that higher CRs require a higher λ and due to practical limitations of the boosting system λ at 4.0 was set as the limit. At a fixed spark timing using a CR of 13.5 combined with λ at 3.33 resulted in an indicated thermal efficiency of 48.6%. It was found that under such lean conditions the exhaust losses were high. Thus advancing the spark time was assessed as a possible solution. The results demonstrated the advantages of advancing the spark time where an indicated thermal efficiency exceeding 50% was achieved while maintaining a very low NOx level. Finally the optimized case in the SI mode was used to investigate the effect of using the PC. For the current design of the PC the results indicated that even though the mixture is lean the flame speed of H2 is sufficiently high to burn the lean charge without using a PC. In addition the PC design used in the current work induced a high MPRR inside the PC and MC leading to an increased tendency to engine knock. The operation with PC also increased the heat transfer losses in the MC leading to lower thermal efficiency compared to the SI mode. Consequently the PC combustion mode needs further optimizations to be employed in hydrogen engine applications.
Low Temperature Autoignition of Diesel Fuel Under Dual Operation with Hydrogen and Hydrogen-carriers
Mar 2022
Publication
While electrification of light duty vehicles is becoming a real solution to abate local pollutant as well as greenhouse gases emission heavy duty applications (such as long distance freight and maritime transport) will keep requiring fuel-based propulsion systems. In these sectors dominated by compression ignition engines research on alternative biofuels and new combustion modes is still highly necessary. Dual-fuel combustion appears as a very promising concept to replace conventional diesel fuel by sustainable ones. Among the latter hydrogen-derived fuels (the so-called electrofuels or e-fuels) are maybe the most interesting. This work addresses the effect of partial substitution of diesel fuel by hydrogen and hydrogen-carriers (ammonia and methane) on the autoignition process under low temperature conditions. Tests were carried out in a constant volume combustion chamber at different temperatures (535 600 and 650 ◦C) and pressures (11 16 and 21 bar). While the cool flames timing and intensity was only slightly affected by the low reactivity fuel energy content the main ignition was delayed this effect being much more noticeable for ammonia followed by hydrogen and finally methane. Kinetic simulations showed a clear competition for active radicals between both fuels (diesel and low reactivity fuel). The combustion duration also increased with the hydrogen or hydrogen-carrier content which greatly points to the need of modifications in the injection strategy of compression ignition engines operating under dual mode. A correlation was proposed for estimating the autoignition delay time for dual-fuel lean combustion at low temperature.
Permeation Tests in Type-approval Regulations for Hydrogen Fuelled Vehicles: Analysis and Testing Experiences at the JRC-GASTEF Facility
Jan 2023
Publication
This article presents an analysis of the permeation tests established in the current regulations for the type-approval of on board tanks in hydrogen vehicles. The analysis is done from the point of view of a test maker regarding the preparation for the execution of a permeation test. The article contains a description of the required instrumentation and set-up to carry out a permeation test according to the applicable standards and regulations. Tank conditions at the beginning of the test configuration of permeation chamber duration of the test or permeation rate to be reported are aspects that are not well-defined in regulations. In this paper we examine the challenges when carrying out a permeation test and propose possible solutions to overcome them with the intention of supporting test makers and helping the development of permeation test guidelines.
Planetary Boundaries Assessment of Deep Decarbonisation Options for Building Heating in the European Union
Jan 2023
Publication
Building heating is one of the sectors for which multiple decarbonisation options exist and current geopolitical tensions provide urgency to design adequate regional policies. Heat pumps and hydrogen boilers alongside alternative district heating systems are the most promising alternatives. Although a host of city or country-level studies exist it remains controversial what role hydrogen should play for building heating in the European Union compared with electrification and how blue and green hydrogen differ in terms of costs and environmental impacts. This works assesses the optimal technology mix for staying within planetary boundaries and the influence of international cooperation and political restrictions. To perform the analysis a bottom-up optimisation model was developed incorporating life cycle assessment constraints and covering production storage transport of energy and carbon dioxide as well as grid and non-grid connected end-users of heat. It was found that a building heating system within planetary boundaries is feasible through large-scale electrification via heat pumps although at a higher cost than the current system with abatement costs of around 200 €/ton CO2. Increasing interconnector capacity or onshore wind energy is found to be vital to staying within boundaries. A strong trade-off for hydrogen was identified with blue hydrogen being cost-competitive but vastly unsustainable (when applied to heating) and green hydrogen being 2–3 times more expensive than electrification while still transgressing several planetary boundaries. The insights from this work indicate that heat pumps and renewable electricity should be prioritised over hydrogen-based heating in most cases and grid-stability and storage aspects explored further while revealing a need for policy instruments to mitigate increased costs for consumers.
Hydrogen Technology for Supply Chain Sustainability: The Mexican Transportation Impacts on Society
Mar 2022
Publication
This study sheds light on the Hydrogen technology in transportation for reaching the sustainability goals of societies illustrated by the case of Mexico. In terms of the affected supply chains the study explores how the packaging and distribution of a fuel-saving tool that allows the adoption of hydrogen as complementary energy for maritime transportation to improve economic and environmental performance in Mexico. This exploratory study performs interviews observations simulations and tests involving producers suppliers and users at 26 ports in Mexico. The study shows that environmental and economic performance are related to key processes in Supply Chain Management (SCM) in which packaging and distribution are critical for achieving logistics and transportation sustainability goals. Reusable packaging and the distribution of a fuel-saving tool can help decrease costs - of transport and downstream/upstream processes in SCM while at the same time increasing the environmental performance.
Investigations on Pressure Dependence of Coriolis Mass Flow Meters Used at Hydrogen Refueling Stations
Sep 2020
Publication
In the framework of the ongoing EMPIR JRP 16ENG01 ‘‘Metrology for Hydrogen Vehicles’’ a main task is to investigate the influence of pressure on the measurement accuracy of Coriolis Mass Flow Meters (CFM) used at Hydrogen Refueling Stations (HRS). At a HRS hydrogen is transferred at very high and changing pressures with simultaneously varying flow rates and temperatures. It is clearly very difficult for CFMs to achieve the current legal requirements with respect to mass flow measurement accuracy at these measurement conditions. As a result of the very dynamic filling process it was observed that the accuracy of mass flow measurement at different pressure ranges is not sufficient. At higher pressures it was found that particularly short refueling times cause significant measurement deviations. On this background it may be concluded that pressure has a great impact on the accuracy of mass flow measurement. To gain a deeper understanding of this matter RISE has built a unique high-pressure test facility. With the aid of this newly developed test rig it is possible to calibrate CFMs over a wide pressure and flow range with water or base oils as test medium. The test rig allows calibration measurements under the conditions prevailing at a 70 MPa HRS regarding mass flows (up to 3.6 kg min−1) and pressures (up to 87.5 MPa).
Economic Evaluation of Renewable Hydrogen Integration into Steelworks for the Production of Methanol and Methane
Jun 2022
Publication
This work investigates the cost-efficient integration of renewable hydrogen into steelworks for the production of methane and methanol as an efficient way to decarbonize the steel industry. Three case studies that utilize a mixture of steelworks off-gases (blast furnace gas coke oven gas and basic oxygen furnace gas) which differ on the amount of used off-gases as well as on the end product (methane and/or methanol) are analyzed and evaluated in terms of their economic performance. The most influential cost factors are identified and sensitivity analyses are conducted for different operating and economic parameters. Renewable hydrogen produced by PEM electrolysis is the most expensive component in this scheme and responsible for over 80% of the total costs. Progress in the hydrogen economy (lower electrolyzer capital costs improved electrolyzer efficiency and lower electricity prices) is necessary to establish this technology in the future.
Optimal Design of Photovoltaic, Biomass, Fuel Cell, Hydrogen Tank Units and Electrolyzer Hybrid System for a Remote Area in Egypt
Jul 2022
Publication
In this paper a new isolated hybrid system is simulated and analyzed to obtain the optimal sizing and meet the electricity demand with cost improvement for servicing a small remote area with a peak load of 420 kW. The major configuration of this hybrid system is Photovoltaic (PV) modules Biomass gasifier (BG) Electrolyzer units Hydrogen Tank units (HT) and Fuel Cell (FC) system. A recent optimization algorithm namely Mayfly Optimization Algorithm (MOA) is utilized to ensure that all load demand is met at the lowest energy cost (EC) and minimize the greenhouse gas (GHG) emissions of the proposed system. The MOA is selected as it collects the main merits of swarm intelligence and evolutionary algorithms; hence it has good convergence characteristics. To ensure the superiority of the selected MOA the obtained results are compared with other well-known optimization algorithms namely Sooty Tern Optimization Algorithm (STOA) Whale Optimization Algorithm (WOA) and Sine Cosine Algorithm (SCA). The results reveal that the suggested MOA achieves the best system design achieving a stable convergence characteristic after 44 iterations. MOA yielded the best EC with 0.2106533 $/kWh the net present cost (NPC) with 6170134 $ the loss of power supply probability (LPSP) with 0.05993% and GHG with 792.534 t/y.
Refueling of LH2 Aircraft—Assessment of Turnaround Procedures and Aircraft Design Implication
Mar 2022
Publication
Green liquid hydrogen (LH2) could play an essential role as a zero-carbon aircraft fuel to reach long-term sustainable aviation. Excluding challenges such as electrolysis transportation and use of renewable energy in setting up hydrogen (H2) fuel infrastructure this paper investigates the interface between refueling systems and aircraft and the impacts on fuel distribution at the airport. Furthermore it provides an overview of key technology design decisions for LH2 refueling procedures and their effects on the turnaround times as well as on aircraft design. Based on a comparison to Jet A-1 refueling new LH2 refueling procedures are described and evaluated. Process steps under consideration are connecting/disconnecting purging chill-down and refueling. The actual refueling flow of LH2 is limited to a simplified Reynolds term of v · d = 2.35 m2/s. A mass flow rate of 20 kg/s is reached with an inner hose diameter of 152.4 mm. The previous and subsequent processes (without refueling) require 9 min with purging and 6 min without purging. For the assessment of impacts on LH2 aircraft operation process changes on the level of ground support equipment are compared to current procedures with Jet A-1. The technical challenges at the airport for refueling trucks as well as pipeline systems and dispensers are presented. In addition to the technological solutions explosion protection as applicable safety regulations are analyzed and the overall refueling process is validated. The thermodynamic properties of LH2 as a real compressible fluid are considered to derive implications for airport-side infrastructure. The advantages and disadvantages of a subcooled liquid are evaluated and cost impacts are elaborated. Behind the airport storage tank LH2 must be cooled to at least 19 K to prevent two-phase phenomena and a mass flow reduction during distribution. Implications on LH2 aircraft design are investigated by understanding the thermodynamic properties including calculation methods for the aircraft tank volume and problems such as cavitation and two-phase flows. In conclusion the work presented shows that LH2 refueling procedure is feasible compliant with the applicable explosion protection standards and hence does not impact the turnaround procedure. A turnaround time comparison shows that refueling with LH2 in most cases takes less time than with Jet A-1. The turnaround at the airport can be performed by a fuel truck or a pipeline dispenser system without generating direct losses i.e. venting to the atmosphere.
PEMFC Poly-Generation Systems: Developments, Merits, and Challenges
Oct 2021
Publication
Significant research efforts are directed towards finding new ways to reduce the cost increase efficiency and decrease the environmental impact of power-generation systems. The poly-generation concept is a promising strategy that enables the development of a sustainable power system. Over the past few years the Proton Exchange Membrane Fuel Cell-based Poly-Generation Systems (PEMFC-PGSs) have received accelerated developments due to the low-temperature operation high efficiency and low environmental impact. This paper provides a comprehensive review of the main PEMFC-PGSs including Combined Heat and Power (CHP) co-generation systems Combined Cooling and Power (CCP) co-generation systems Combined Cooling Heat and Power (CCHP) tri-generation systems and Combined Water and Power (CWP) co-generation systems. First the main technologies used in PEMFC-PGSs such as those related to hydrogen production energy storage and Waste Heat Recovery (WHR) etc. are detailed. Then the research progresses on the economic energy and environmental performance of the different PEMFC-PGSs are presented. Also the recent commercialization activities on these systems are highlighted focusing on the leading countries in this field. Furthermore the remaining economic and technical obstacles of these systems along with the future research directions to mitigate them are discussed. The review reveals the potential of the PEMFC-PGS in securing a sustainable future of the power systems. However many economic and technical issues particularly those related to high cost and degradation rate still need to be addressed before unlocking the full benefits of such systems.
Trends in the Global Steel Industry: Evolutionary Projections and Defossilisation Pathways through Power-to-steel
Sep 2022
Publication
Steel production is a carbon and energy intensive activity releasing 1.9 tons of CO2 and requiring 5.17 MWh of primary energy per ton produced on average globally resulting in 9% of all anthropogenic CO2 emissions. To achieve the goals of the Paris Agreement of limiting global temperature increase to below 1.5 °C compared to pre-industrial levels the structure of the global steel production must change fundamentally. There are several technological paths towards a lower carbon intensity for steelmaking which bring with them a paradigm shift decoupling CO2 emissions from crude steel production by transitioning from traditional methods of steel production using fossil coal and fossil methane to those based on low-cost renewable electricity and green hydrogen. However the energy system consequences of fully defossilised steelmaking has not yet been examined in detail. This research examines the energy system requirements a global defossilised power-to-steel industry using a GDP-based demand model for global steel demands which projects a growth in steel demand from 1.6 Gt in 2020 to 2.4 Gt in 2100. Three scenarios are developed to investigate the emissions trajectory energy demands and economics of a high penetration of direct hydrogen reduction and electrowinning in global steel production. Results indicate that the global steel industry will see green hydrogen demands grow significantly ranging from 2809 to 4371 TWhH2 by 2050. Under the studied conditions global steel production is projected to see reductions in final thermal energy demand of between 38.3% and 57.7% and increases in total electricity demand by factors between 15.1 and 13.3 by 2050 depending on the scenario. Furthermore CO2 emissions from steelmaking can be reduced to zero.
Optimal Battery and Hydrogen Fuel Cell Sizing in Heavy-haul Locomotives
Jul 2023
Publication
Global supply chains must be decarbonised as part of meeting climate targets set by the United Nations and world leaders. Rail networks are vital infrastructure in passenger and freight transport however have not received the same push for decarbonisation as road transport. In this investigation we used real world data from locomotives operating on seven rail corridors to identify optimal battery capacity and hydrogen fuel cell (HFC) power in hybrid systems. We found that the required battery capacity is dependent on both the available regenerative braking energy and on the capacity required to buffer surpluses and deficits from the HFC. The optimal system for each corridor was identified however it was found that one 3.6 MWh battery and 860 kW HFC system could service six of the seven corridors. The optimal systems presented in this work suggest an average of around 5 h of battery storage for the HFC power which is larger than the 2 h previously reported in literature. This may indicate a gap between purely theoretical works that use only route topography and speed and those that employ real world locomotive data.
A Zero CO2 Emissions Large Ship Fuelled by an Ammonia-hydrogen Blend: Reaching the Decarbonisation Goals
Aug 2023
Publication
To reach the decarbonisation goals a zero CO2 emissions large ship propulsion system is proposed in this work. The ship selected is a large ferry propelled by an internal combustion engine fuelled by an ammonia-hydrogen blend. The only fuel loaded in the vessel will be ammonia. The hydrogen required for the combustion in the engine will be produced onboard employing ammonia decomposition. The heat required for this decomposition section will be supplied by using the hot flue gases of the combustion engine. To address the issues regarding NOx emissions a selective catalytic reduction (SCR) reactor was designed. The main operating variables for all the equipment were computed for engine load values of 25% 50% 75% and 100%. Considering the lowest SCR removal rate (91% at an engine load of 100%) the NOx emissions of the vessel were less than 0.5 g/kWh lower than the IMO requirements. An energy analysis of the system proposed to transform ammonia into energy for shipping was conducted. The global energy and exergy efficiencies were 42.4% and 48.1%. In addition an economic analysis of the system was performed. The total capital cost (CAPEX) for the system can be estimated at 8.66 M€ (784 €/kW) while the operating cost (OPEX) ranges between 210 €/MWh (engine load 100%) and 243 €/MWh (engine load of 25%). Finally a sensitivity analysis for the price of ammonia was performed resulting in the feasibility of reducing the operating cost to below 150 €/MWh in the near horizon.
Bioinspired Hybrid Model to Predict the Hydrogen Inlet Fuel Cell Flow Change of an Energy Storage System
Nov 2019
Publication
The present research work deals with prediction of hydrogen consumption of a fuel cell in an energy storage system. Due to the fact that these kind of systems have a very nonlinear behaviour the use of traditional techniques based on parametric models and other more sophisticated techniques such as soft computing methods seems not to be accurate enough to generate good models of the system under study. Due to that a hybrid intelligent system based on clustering and regression techniques has been developed and implemented to predict the necessary variation of the hydrogen flow consumption to satisfy the variation of demanded power to the fuel cell. In this research a hybrid intelligent model was created and validated over a dataset from a fuel cell energy storage system. Obtained results validate the proposal achieving better performance than other well-known classical regression methods allowing us to predict the hydrogen consumption with a Mean Absolute Error (MAE) of 3.73 with the validation dataset.
Techno-Economic Analysis of Solid Oxide Fuel Cell-Gas Turbine Hybrid Systems for Stationary Power Applications Using Renewable Hydrogen
Jun 2023
Publication
Solid oxide fuel cell (SOFC)–gas turbine (GT) hybrid systems can produce power at high electrical efficiencies while emitting virtually zero criteria pollutants (e.g. ozone carbon monoxide oxides of nitrogen and sulfur and particulate matters). This study presents new insights into renewable hydrogen (RH2 )-powered SOFC–GT hybrid systems with respect to their system configuration and techno-economic analysis motivated by the need for clean on-demand power. First three system configurations are thermodynamically assessed: (I) a reference case with no SOFC off-gas recirculation (II) a case with cathode off-gas recirculation and (III) a case with anode off-gas recirculation. While these configurations have been studied in isolation here we provide a detailed performance comparison. Moreover a techno-economic analysis is conducted to study the economic competitiveness of RH2 -fueled hybrid systems and the economies of scale by offering a comparison to natural gas (NG)-fueled systems. Results show that the case with anode off-gas recirculation with 68.50%-lower heating value (LHV) at a 10 MW scale has the highest efficiency among the studied scenarios. When moving from 10 MW to 50 MW the efficiency increases to 70.22%-LHV. These high efficiency values make SOFC–GT hybrid systems highly attractive in the context of a circular economy as they outcompete most other power generation technologies. The cost-of-electricity (COE) is reduced by about 10% when moving from 10 MW to 50 MW from USD 1976/kW to USD 1668/kW respectively. Renewable H2 is expected to be economically competitive with NG by 2030 when the U.S. Department of Energy’s target of USD 1/kg RH2 is reached.
Hydrogen Supply Chain and Refuelling Network Design: Assessment of Alternative Scenarios for the Long-haul Road Freight in the UK
Mar 2023
Publication
Shifting from fossil fuels to clean alternative fuel options such as hydrogen is an essential step in decarbonising the road freight transport sector and facilitating an efficient transition towards zero-emissions goods distribution of the future. Designing an economically viable and competitive Hydrogen Supply Chain (HSC) to support and accelerate the widespread adoption of hydrogen powered Heavy Goods Vehicles (H2-HGVs) is however significantly hindered by the lack of the infrastructure required for producing storing transporting and distributing the required hydrogen. This paper focuses on a bespoke design of a hydrogen supply chain and distribution network for the long-haul road freight transportation in the UK and develops an improved end-to-end and spatially-explicit optimisation tool to perform scenario analysis and provide important first-hand managerial and policy making insights. The proposed methodology improves over existing grid-based methodologies by incorporating spatially-explicit locations of Hydrogen Refuelling Stations (HRSs) and allowing further flexibility and accuracy. Another distinctive feature of the method and the analyses carried out in the paper pertains to the inclusion of bulk geographically agnostic as well as geological underground hydrogen storage options and reporting on significant cost saving opportunities. Finally the curve for H2-HGVs penetration levels safety stock period decisions and the transport mode capacity against hydrogen levelized cost at pump have been generated as important policy making tools to provide decision support and insights into cost resilience and reliability of the HSC.
Effect of Carbon Monoxide on Polymer Electrolyte Fuel Cell Performance with a Hydrogen Circulation System
Feb 2022
Publication
The effect of carbon monoxide (CO) on the performance of polymer electrolyte fuel cells (PEFCs) with either a hydrogen circulation system or a hydrogen one-way pass system is investigated and compared. The voltage drop induced by adding 0.2 ppm of CO to the PEFC with the hydrogen circulation system was less than one-tenth of that observed in the PEFC with the hydrogen one-way pass system at 1000 mA cm–2 and a cell temperature of 60 °C. Gas analysis results showed that CO concentration in the hydrogen circulation system was lower than the initially supplied CO concentration. In the hydrogen circulation system permeated oxygen from the cathode should enhance CO oxidation. This should lead to decrease the CO concentration and mitigate the voltage drop in the hydrogen circulation system.
Analysis of CO2 Emissions Reduction on the Future Hydrogen Supply Chain Network for Dubai Buses
Apr 2023
Publication
There is an impetus to decarbonize transportation sector and mitigate climate change. This study examines the effect of adopting hydrogen (H2) as a fuel for Dubai Buses at different penetration scales on carbon dioxide (CO2) emissions reduction. A H2 supply-chain system dynamics model is developed to conduct life cycle cost and environmental analysis and evaluate the efficacy of different carbon prices and subsidies. Gray green and mixed H2 production scenarios were considered. The results show that gray hydrogen reduces 7.1 million tons of CO2 which is half of green hydrogen buses. Replacing diesel fleet at end of lifetime with mixed hydrogen bus fleet was the optimal approach to promote green hydrogen at pump reaching $4/kg in a decade. This gradual transition reduces 62% of the well-to-wheel CO2 emissions of the new bus fleet and creates mass for economies of scale as carbon prices and subsidies cannot promote green hydrogen alone.
Progress in Electrical Energy Storage System: A Critical Review
Jan 2009
Publication
Electrical energy storage technologies for stationary applications are reviewed. Particular attention is paid to pumped hydroelectric storage compressed air energy storage battery flow battery fuel cell solar fuel superconducting magnetic energy storage flywheel capacitor/supercapacitor and thermal energy storage. Comparison is made among these technologies in terms of technical characteristics applications and deployment status.
Investigating the Impact of Economic Uncertainty on Optimal Sizing of Grid-Independent Hybrid Renewable Energy Systems
Aug 2021
Publication
One of the many barriers to decarbonization and decentralization of the energy sector in developing countries is the economic uncertainty. As such this study scrutinizes economics of three grid-independent hybrid renewable-based systems proposed to co-generate electricity and heat for a small-scale load. Accordingly the under-study systems are simulated and optimized with the aid of HOMER Pro software. Here a 20-year average value of discount and inflation rates is deemed a benchmark case. The techno-economic-environmental and reliability results suggest a standalone solar/wind/electrolyzer/hydrogen-based fuel cell integrated with a hydrogen-based boiler system is the best alternative. Moreover to ascertain the impact of economic uncertainty on optimal unit sizing of the nominated model the fluctuations of the nominal discount rate and inflation respectively constitute within the range of 15–20% and 10–26%. The findings of economic uncertainty analysis imply that total net present cost (TNPC) fluctuates around the benchmark value symmetrically between $478704 and $814905. Levelized energy cost varies from an amount 69% less than the benchmark value up to two-fold of that. Furthermore photovoltaic (PV) optimal size starts from a value 23% less than the benchmark case and rises up to 55% more. The corresponding figures for wind turbine (WT) are respectively 21% and 29%. Eventually several practical policies are introduced to cope with economic uncertainty.
Numerical Redesign of 100kw MGT Combustor for 100% H2 Fueling
Jan 2014
Publication
The use of hydrogen as energy carrier in a low emission microturbine could be an interesting option for renewable energy storage distributed generation and combined heat & power. However the hydrogen using in gas turbine is limited by the NOx emissions and the difficulty to operate safely. CFD simulations represent a powerful and mature tool to perform detailed 3-D investigation for the development of a prototype before carrying out an experimental analysis. This paper describes the CFD supported redesign of the Turbec T100 microturbine combustion chamber natural gas-fired to allow the operation on 100% hydrogen.
Fuelling the Transition Podcast: How Will Hydrogen Heat and Safety in the Home?
Jan 2022
Publication
In this episode Angela Needle Director of Strategy at Cadent and John Williams Head of Hydrogen Expertise Cluster at AFRY Management Consulting join us to discuss a range of topics concerning hydrogen and the energy transition. This includes Cadent’s involvement in hydrogen through HyNet the role of hydrogen in heat safety and plans for the first hydrogen village. They also explore Angela’s role as co-founder of the Women’s Utilities Network a group focussed on helping women develop their skills within the energy space.
The podcast can be found on their website.
The podcast can be found on their website.
An Extensive Review of Liquid Hydrogen in Transportation with Focus on the Maritime Sector
Sep 2022
Publication
The European Green Deal aims to transform the EU into a modern resource-efficient and competitive economy. The REPowerEU plan launched in May 2022 as part of the Green Deal reveals the willingness of several countries to become energy independent and tackle the climate crisis. Therefore the decarbonization of different sectors such as maritime shipping is crucial and may be achieved through sustainable energy. Hydrogen is potentially clean and renewable and might be chosen as fuel to power ships and boats. Hydrogen technologies (e.g. fuel cells for propulsion) have already been implemented on board ships in the last 20 years mainly during demonstration projects. Pressurized tanks filled with gaseous hydrogen were installed on most of these vessels. However this type of storage would require enormous volumes for large long-range ships with high energy demands. One of the best options is to store this fuel in the cryogenic liquid phase. This paper initially introduces the hydrogen color codes and the carbon footprints of the different production techniques to effectively estimate the environmental impact when employing hydrogen technologies in any application. Afterward a review of the implementation of liquid hydrogen (LH2 ) in the transportation sector including aerospace and aviation industries automotive and railways is provided. Then the focus is placed on the maritime sector. The aim is to highlight the challenges for the adoption of LH2 technologies on board ships. Different aspects were investigated in this study from LH2 bunkering onboard utilization regulations codes and standards and safety. Finally this study offers a broad overview of the bottlenecks that might hamper the adoption of LH2 technologies in the maritime sector and discusses potential solutions.
Carbon Footprint and Energy Transformation Analysis of Steel Produced via a Direct Reduction Plant with an Integrated Electric Melting Unit
Aug 2022
Publication
The production of fat steel products is commonly linked to highly integrated sites which include hot metal generation via the blast furnace basic oxygen furnace (BOF) continuous casting and subsequent hot-rolling. In order to reach carbon neutrality a shift away from traditional carbon-based metallurgy is required within the next decades. Direct reduction (DR) plants are capable to support this transition and allow even a stepwise reduction in CO2 emissions. Nevertheless the implementation of these DR plants into integrated metallurgical plants includes various challenges. Besides metallurgy product quality and logistics special attention is given on future energy demand. On the basis of carbon footprint methodology (ISO 14067:2019) diferent scenarios of a stepwise transition are evaluated and values of possible CO2equivalent (CO2eq) reduction are coupled with the demand of hydrogen electricity natural gas and coal. While the traditional blast furnace—BOF route delivers a surplus of electricity in the range of 0.7 MJ/kg hot-rolled coil; this surplus turns into a defcit of about 17 MJ/ kg hot-rolled coil for a hydrogen-based direct reduction with an integrated electric melting unit. On the other hand while the product carbon footprint of the blast furnace-related production route is 2.1 kg CO2eq/kg hot-rolled coil; this footprint can be reduced to 0.76 kg CO2eq/kg hot-rolled coil for the hydrogen-related route provided that the electricity input is from renewable energies. Thereby the direct impact of the processes of the integrated site can even be reduced to 0.15 kg CO2eq/ kg hot-rolled coil. Yet if the electricity input has a carbon footprint of the current German or European electricity grid mix the respective carbon footprint of hot-rolled coil even increases up to 3.0 kg CO2eq/kg hot-rolled coil. This underlines the importance of the availability of renewable energies.
A Model for Cost- and Greenhouse Gas Optimal Material and Energy Allocation of Biomass and Hydrogen
Nov 2022
Publication
BENOPT an optimal material and energy allocation model is presented which is used to assess cost-optimal and/or greenhouse gas abatement optimal allocation of renewable energy carriers across power heat and transport sectors. A high level of detail on the processes from source to end service enables detailed life-cycle greenhouse gas and cost assessments. Pareto analyses can be performed as well as thorough sensitivity analyses. The model is designed to analyse optimal biomass and hydrogen usage as a complement to integrated assessment and power system models
A Study on Green Hydrogen-based Isolated Microgrid
Oct 2022
Publication
This paper assesses the techno-economic feasibility of a green hydrogen-based microgrid for a remote Australian island. Hydrogen can be used to provide clean energy in areas where large-scale renewable energy sources are not feasible owing to geography government regulations or regulatory difficulties. This study not only identifies the appropriate component size for a hydrogen-based microgrid but also provides an economic perspective of decarbonising Thursday Island in Torres Straits Queensland Australia. Due to geographical constraints the green hydrogen production system needs to be distinct from the electrical network. This research shows how to produce green hydrogen transport it and generate power at a low cost. The study was performed utilising the HOMER simulation platform to find the least cost solution. The simulation results demonstrate an AU$0.01 reduction in Levelised Cost of Energy compared to the present electricity generation cost which is AU$0.56. The inclusion of a green hydrogen system will potentially minimise CO2 emissions by 99.6% while ensuring almost 100% renewable penetration. The results of this study will also serve as a guide for the placement of hydrogen-based microgrids in similar remote locations around the world where numerous remote energy systems are located close to each other.
Residential Fuel Transition and Fuel Interchangeability in Current Self-Aspirating Combustion Applications: Historical Development and Future Expectations
May 2022
Publication
To reduce greenhouse gases and air pollutants new technologies are emerging to reduce fossil fuel usage and to adopt more renewable energy sources. As the major aspects of fuel consumption power generation transportation and industrial applications have been given significant attention. The past few decades witnessed astonishing technological advancement in these energy sectors. In contrast the residential sector has had relatively little attention despite its significant utilization of fuels for a much longer period. However almost every energy transition in human history was initiated by the residential sector. For example the transition from fuelwood to cheap coal in the 1700s first took place in residential houses due to urbanization and industrialization. The present review demonstrates the energy transitions in the residential sector during the past two centuries while portending an upcoming energy transition and future energy structure for the residential sector. The feasibility of the 100% electrification of residential buildings is discussed based on current residential appliance adoption and the analysis indicates a hybrid residential energy structure is preferred over depending on a single energy source. Technical considerations and suggestions are given to help incorporate more renewable energy into the residential fuel supply system. Finally it is observed that compared to the numerous regulations on large energy-consumption aspects standards for residential appliances are scarce. Therefore it is concluded that establishing appropriate testing methods is a critical enabling step to facilitate the adoption of renewable fuels in future appliances.
Batteries, Fuel Cells, or Engines? A Probabilistic Economic and Environmental Assessment of Electricity and Electrofuels for Heavy Goods Vehicles
Oct 2022
Publication
Uncertainty surrounding the total cost of ownership system costs and life cycle environmental impacts means that stakeholders may lack the required information to evaluate the risks of transitioning to low-carbon fuels and powertrains. This paper assesses the life cycle costs and well-to-wheel environmental impacts of using electricity and electrofuels in Heavy Good Vehicles (HGVs) whilst considering input parameter uncertainty. The complex relationship between electricity cost electrolyser capacity factor CO2 capture cost and electricity emissions intensity is assessed within a Monte Carlo based framework to identify scenarios where use of electricity or electrofuels in heavy goods vehicles makes economic and environmental sense. For vehicles with a range of less than 450 km battery electric vehicles achieve the lowest total cost of ownership for an electricity cost less than 100 €/MWh. For vehicles that require a range of up to 900 km hydrogen fuel cell vehicles represent the lowest long-term cost of abatement. Power-to-methane and power-to-liquid scenarios become economically competitive when low-cost electricity is available at high-capacity factors and CO2 capture costs for fuel synthesis are below 100 €/tCO2; these fuels may be more applicable to decarbonise shipping and aviation. Battery electric HGVs reduce greenhouse gas emissions by 50% compared to the diesel baseline with electricity emissions of 350 gCO2e/kWh. Electricity emissions less than 35 gCO2e/kWh are required for the power-to-methane and power-to-liquid scenarios to meet EU emissions savings criteria. High vehicle capital costs and a lack of widespread refuelling infrastructure may hinder initial uptake of low-carbon fuels and powertrains for HGVs.
Fuel Cell Electrical Vehicles as Mobile Coupled Heat and Power Backup-Plant in Neighbourhoods
Apr 2022
Publication
Fuel cell electric vehicles (FCEVs) can be used during idle times to convert hydrogen into electricity in a decentralised manner thus ensuring a completely renewable energy supply. In addition to the electric power waste heat is generated in the fuel cell stack that can also be used. This paper investigates how the energy demand of a compiled German neighbourhood can be met by FCEVs and identifies potential technical problems. For this purpose energy scenarios are modelled in the Open Energy System Modelling Framework (oemof). An optimisation simulation finds the most energetically favourable solution for the 10-day period under consideration. Up to 49% of the heat demand for heating and hot water can be covered directly by the waste heat of the FCEVs. As the number of battery electric vehicles (BEVs) to be charged increases so does this share. 5 of the 252 residents must permanently provide an FCEV to supply the neighbourhood. The amount of hydrogen required was identified as a problem. If the vehicles cannot be supplied with hydrogen in a stationary way 15 times more vehicles are needed than required in terms of performance due to the energy demand.
Iron as Recyclable Energy Carrier: Feasibility Study and Kinetic Analysis of Iron Oxide Reduction
Oct 2022
Publication
Carbon-free and sustainable energy storage solutions are required to mitigate climate change. One possible solution especially for stationary applications could be the storage of energy in metal fuels. Energy can be stored through reduction of the oxide with green hydrogen and be released by combustion. In this work a feasibility study for iron as possible metal fuel considering the complete energy cycle is conducted. Based on equilibrium calculations it could be shown that the power-to-power efficiency of the iron/iron oxide cycle is 27 %. As technology development requires a more detailed description of both the reduction and the oxidation a first outlook is given on the kinetic analysis of the reduction of iron oxides with hydrogen. Based on thermogravimetric experiments using Fe2O3 Fe3O4 and FeO it could be shown that the reduction is a three-step process. The maximum reduction rate can be achieved with a hydrogen content of 25 %. Based on the experimental results a reaction mechanism and accompanied kinetic data were developed for description of Fe2O3 reduction with H2 under varying experimental conditions.
Reduction Kinetics of Hematite Powder in Hydrogen Atmosphere at Moderate Temperatures
Sep 2018
Publication
Hydrogen has received much attention in the development of direct reduction of iron ores because hydrogen metallurgy is one of the effective methods to reduce CO2 emission in the iron and steel industry. In this study the kinetic mechanism of reduction of hematite particles was studied in a hydrogen atmosphere. The phases and morphological transformation of hematite during the reduction were characterized using X-ray diffraction and scanning electron microscopy with energy dispersive spectroscopy. It was found that porous magnetite was formed and the particles were degraded during the reduction. Finally sintering of the reduced iron and wüstite retarded the reductive progress. The average activation energy was extracted to be 86.1 kJ/mol and 79.1 kJ/mol according to Flynn-Wall-Ozawa (FWO) and Starink methods respectively. The reaction fraction dependent values of activation energy were suggested to be the result of multi-stage reactions during the reduction process. Furthermore the variation of activation energy value was smoothed after heat treatment of hematite particles.
Techno-economic Modelling of Zero-emission Marine Transport with Hydrogen Fuel and Superconducting Propulsion System: Case Study of a Passenger Ferry
Mar 2023
Publication
This paper proposes a techno-economic model for a high-speed hydrogen ferry. The model can describe the system properties i.e. energy demand weight and daily operating expenses of the ferry. A novel aspect is the consideration of superconductivity as a measure for cost saving in the setting where liquid hydrogen (LH2) can be both coolant and fuel. We survey different scenarios for a high-speed ferry that could carry 300 passengers. The results show that despite higher energy demand compressed hydrogen gas is more economical compared with LH2 for now; however constructing large-scale hydrogen liquefaction plants make it competitive in the future. Moreover compressed hydrogen gas is restricted to a shorter distance while LH2 makes longer distances possible and whenever LH2 is accessible using a superconducting propulsion system has a beneficial impact on both energy and cost savings. These effects strengthen if the operational time or the weight of the ferry increases.
Smart Energy Management System: Design of a Smart Grid Test Bench for Educational Purposes
Apr 2022
Publication
The presented article aims to design an educational test bench setup for smart grids and renewable energies with multiple features and techniques used in a microgrid. The test bench is designed for students laboratory engineers and researchers which enables electrical microgrid system studies and testing of new advanced control algorithms to optimize the energy efficiency. The idea behind this work is to design hybrid energy sources such as wind power solar photovoltaic power hydroelectric power hydrogen energy and different types of energy storage systems such as batteries pumped storage and flywheel integrating different electrical loads. The user can visualize the state of the components of each emulated scenario through an open-source software that interacts and communicates using OPC Unified Architecture protocol. The researchers can test and validate new solutions to manage the energy behavior in the grid using machine learning and optimization algorithms integrated in the software in form of blocks that can be modified and improved and then simulate the results. A model-based system of engineering is provided which describes the different requirements and case studies of the designed test bench respecting the open-source software and the frugal innovation features in which there is use of low-cost hardware and open-source software. The users obtain the opportunity to add new sources and new loads change software platforms and communicate with other simulators and equipment. The students can understand the different features of smart grids such as defect classification energy forecasting energy optimization and basics of production transmission and consumption.
Delivering a Reliable Decarbonised Power System
Mar 2023
Publication
This report illustrates what a reliable resilient decarbonised electricity supply system could look like in 2035 and the steps required to achieve it. It provides new insights and new advice on how such a system can be achieved by 2035 using real weather data and hourly analysis of Great Britain’s power system (Northern Ireland is part of the all-Ireland system). It also looks at the implications for hydrogen.
Review on the Safe Use of Ammonia Fuel Cells in the Maritime Industry
May 2021
Publication
In April 2018 the International Maritime Organisation adopted an ambitious plan to contribute to the global efforts to reduce the Greenhouse Gas emissions as set by the Paris Agreement by targeting a 50% reduction in shipping’s Green House Gas emissions by 2050 benchmarked to 2008 levels. To meet these challenging goals the maritime industry must introduce environmentally friendly fuels with negligible or low SOX NOX and CO2 emissions. Ammonia use in maritime applications is considered promising due to its high energy density low flammability easy storage and low production cost. Moreover ammonia can be used as fuel in a variety of propulsors such as fuel cells and can be produced from renewable sources. As a result ammonia can be used as a versatile marine fuel exploiting the existing infrastructure and having zero SOX and CO2 emissions. However there are several challenges to overcome for ammonia to become a compelling fuel towards the decarbonisation of shipping. Such factors include the selection of the appropriate ammonia-fuelled power generator the selection of the appropriate system safety assessment tool and mitigating measures to address the hazards of ammonia. This paper discusses the state-of-the-art of ammonia fuelled fuel cells for marine applications and presents their potential and challenges.
Improving Ecological Efficiency of Gas Turbine Power System by Combusting Hydrogen and Hydrogen-Natural Gas Mixtures
Apr 2023
Publication
Currently the issue of creating decarbonized energy systems in various spheres of life is acute. Therefore for gas turbine power systems including hybrid power plants with fuel cells it is relevant to transfer the existing engines to pure hydrogen or mixtures of hydrogen with natural gas. However significant problems arise associated with the possibility of the appearance of flashback zones and acoustic instability of combustion an increase in the temperature of the walls of the flame tubes and an increase in the emission of nitrogen oxides in some cases. This work is devoted to improving the efficiency of gas turbine power systems by combusting pure hydrogen and mixtures of natural gas with hydrogen. The organization of working processes in the premixed combustion chamber and the combustion chamber with a sequential injection of ecological and energy steam for the “Aquarius” type power plant is considered. The conducted studies of the basic aerodynamic and energy parameters of a gas turbine combustor working on hydrogen-containing gases are based on solving the equations of conservation and transfer in a multicomponent reacting system. A four-stage chemical scheme for the burning of a mixture of natural gas and hydrogen was used which allows for the rational parameters of environmentally friendly fuel burning devices to be calculated. The premixed combustion chamber can only be recommended for operations on mixtures of natural gas with hydrogen with a hydrogen content not exceeding 20% (by volume). An increase in the content of hydrogen leads to the appearance of flashback zones and fuel combustion inside the channels of the swirlers. For the combustion chamber of the combined-cycle power plant “Vodoley” when operating on pure hydrogen the formation of flame flashback zones does not occur.
Multi-Model Assessment for Secondary Smelting Decarbonisation: The Role of Hydrogen in the Clean Energy Transition
Jan 2023
Publication
Extensive decarbonisation efforts result in major changes in energy demand for the extractive industry. In 2021 the extraction and primary processing of metals and minerals accounted for 4.5 Gt of CO2 eq. per year. The aluminium industry was responsible for 1.1 Gt CO2 eq. direct and indirect emissions. To reach the European milestone of zero emissions by 2050 a reduction of 3% annually is essential. To this end the industry needs to take a turn towards less impactful production practices coupling secondary production with green energy sources. The present work aims to comprehensively compare the lifecycle energy consumption and environmental performance of a secondary aluminium smelter employing alternative thermal and electricity sources. In this frame a comparative analysis of the environmental impact of different thermal energy sources namely natural gas light fuel oil liquified petroleum gas hydrogen and electricity for a secondary aluminium smelter is presented. The results show that H2 produced by renewables (green H2 ) is the most environmentally beneficial option accounting for −84.156 kg CO2 eq. By producing thermal energy as well as electricity on site H2 technologies also serve as a decentralized power station for green energy production. These technologies account for a reduction of 118% compared to conventionally used natural gas. The results offer a comprehensive overview to aid decision-makers in comparing environmental impacts caused by different energy sources.
Can Hydrogen Production Be Economically Viable on the Existing Gas-Fired Power Plant Location? New Empirical Evidence
Apr 2023
Publication
The paper provides an economic model for the assessment of hydrogen production at the site of an existing thermal power plant which is then integrated into the existing gas grid. The model uses projections of electricity prices natural gas prices and CO2 prices as well as estimates of the cost of building a power-to-gas system for a 25-year period. The objective of this research is to calculate the yellow hydrogen production price for each lifetime year of the Power-to-gas system to evaluate yellow hydrogen competitiveness compared to the fossil alternatives. We test if an incentive scheme is needed to make this technology economically viable. The research also provides several sensitivity scenarios of electricity natural gas and CO2 price changes. Our research results clearly prove that yellow hydrogen is not yet competitive with fossil alternatives and needs incentive mechanisms for the time being. At given natural gas and CO2 prices the incentive for hydrogen production needs to be 52.90 EUR/MWh in 2025 and 36.18 EUR/MWh in 2050. However the role of hydrogen in the green transition could be very important as it provides ancillary services and balances energy sources in the power system.
Economic Operation Strategy of Integrated Hydrogen Energy System Considering the Uncertainty of PV Power Output
Jan 2023
Publication
To address the negative influence caused by power randomness of distributed PV output on energy system’s economic operation in this work an economic operation strategy considering the uncertainty features of PV output has been designed and applied on an integrated hydrogen energy system. First the thermal system operation model and the thermoelectric output control model are precisely built for the integrated hydrogen energy system and the hydrogen-based fuel cell respectively. Then referring to the PV output prediction data the uncertainty of light intensity variation is analyzed to correct the PV output prediction curve. Finally a cost–benefit model for the optimal economic operation of the integrated hydrogen energy system including PV hydrogen fuel cell and cogeneration unit is designed with an objective function of achieving an optimal economic operation of the multi-energy coupling devices. The simulation tests validate that considering the influence of PV output uncertainty on hydrogen fuel cell output can make the system operation more reasonable which ensures the economic and reliable operation of hydrogen energy systems.
Increasing Technical Efficiency of Renewable Energy Sources in Power Systems
Mar 2023
Publication
This paper presents a method for refining the forecast schedule of renewable energy sources (RES) generation by its intraday adjustment and investigates the measures for reserving RES with unstable generation in electric power systems (EPSs). Owing to the dependence of electricity generation by solar and wind power plants (PV and WPPs respectively) on natural conditions problems arise with their contribution to the process of balancing the power system. Therefore the EPS is obliged to keep a power reserve to compensate for deviations in RES from the planned generation amount. A system-wide reserve (mainly the shunting capacity of thermal and hydroelectric power plants) is used first followed by other means of power reserve: electrochemical hydrogen or biogas plants. To analyze the technical and economic efficiency of certain backup means mathematical models based on the theory of similarity and the criterion method were developed. This method is preferred because it provides the ability to compare different methods of backing up RES generation with each other assess their proportionality and determine the sensitivity of costs to the capacity of backup methods with minimal available initial information. Criterion models have been formed that allow us to build dependencies of the costs of backup means for unstable RES generation on the capacity of the backup means. It is shown that according to the results of the analysis of various methods and means of RES backup hydrogen technologies are relatively the most effective. The results of the analysis in relative units can be clarified if the current and near-term price indicators are known.
Hydrogen Fuel Cell Vehicle Development in China: An Industry Chain Perspective
Jun 2020
Publication
Hydrogen fuel cell vehicle (FCV) technology has significant implications on energy security and environmental protection. In the past decade China has made great progress in the hydrogen and FCV industry considering both the government’s policy issuances and enterprises’ production. However there are still some technological and cost challenges obstructing the commercialization of FCVs. Herein the status of China’s hydrogen FCV industry is analyzed comprehensively from three perspectives: policy support market application and technology readiness level. The unique characteristics and key issues in each part of the industry chain are emphasized. Furthermore the energy environmental and economic performances of FCV in the life-cycle perspective are reviewed and summarized based on pre-existing literature and reports. The life-cycle analysis of hydrogen and FCV indicates that the energy and environmental impacts of FCVs are highly related to the sources of hydrogen. With the combination of industry status and technology performances it is highlighted that technology advancements in hydrogen production and fuel cells and the optimization of the manufacturing processes for fuel cell systems are equally essential in the development of hydrogen FCVs.
Comparative TCO Analysis of Battery Electric and Hydrogen Fuel Cell Buses for Public Transport System in Small to Midsize Cities
Jul 2021
Publication
This paper shows the results of an in-depth techno-economic analysis of the public transport sector in a small to midsize city and its surrounding area. Public battery-electric and hydrogen fuel cell buses are comparatively evaluated by means of a total cost of ownership (TCO) model building on historical data and a projection of market prices. Additionally a structural analysis of the public transport system of a specific city is performed assessing best fitting bus lines for the use of electric or hydrogen busses which is supported by a brief acceptance evaluation of the local citizens. The TCO results for electric buses show a strong cost decrease until the year 2030 reaching 23.5% lower TCOs compared to the conventional diesel bus. The optimal electric bus charging system will be the opportunity (pantograph) charging infrastructure. However the opportunity charging method is applicable under the assumption that several buses share the same station and there is a “hotspot” where as many as possible bus lines converge. In the case of electric buses for the year 2020 the parameter which influenced the most on the TCO was the battery cost opposite to the year 2030 in where the bus body cost and fuel cost parameters are the ones that dominate the TCO due to the learning rate of the batteries. For H2 buses finding a hotspot is not crucial because they have a similar range to the diesel ones as well as a similar refueling time. H2 buses until 2030 still have 15.4% higher TCO than the diesel bus system. Considering the benefits of a hypothetical scaling-up effect of hydrogen infrastructures in the region the hydrogen cost could drop to 5 €/kg. In this case the overall TCO of the hydrogen solution would drop to a slightly lower TCO than the diesel solution in 2030. Therefore hydrogen buses can be competitive in small to midsize cities even with limited routes. For hydrogen buses the bus body and fuel cost make up a large part of the TCO. Reducing the fuel cost will be an important aspect to reduce the total TCO of the hydrogen bus.
Prioritization and Optimal Location of Hydrogen Fueling Stations in Seoul: Using Multi-Standard Decision-Making and ILP Optimization
Mar 2023
Publication
Thus far the adoption of hydrogen fuel cell vehicles (HCEVs) has been hampered by the lack of hydrogen fueling infrastructure. This study aimed to determine the optimal location and prioritization of hydrogen fueling stations (HFSs) in Seoul by utilizing a multi-standard decision making approach and optimization method. HFS candidate sites were evaluated with respect to relevant laws and regulations. Key factors such as safety economy convenience and demand for HCEVs were considered. Data were obtained through a survey of experts in the fields of HCEV and fuel cells and the Analytic Hierarchy Process method was applied to prioritize candidate sites. The optimal quantity and placement of HFSs was then obtained using optimization software based on the acceptable travel time from intersections of popular roads in Seoul. Our findings suggest that compliance with legal safety regulations is the most important factor when constructing HFSs. Furthermore sensitivity analysis revealed that the hydrogen supply cost currently holds the same weight as other elements. The study highlights the importance of utilizing a multi-standard decision-making approach and optimization methods when determining the optimal location and prioritization of HFSs and can help develop a systematic plan for the nationwide construction of HFSs in South Korea.
Cost-optimal Reliable Power Generation in a Deep Decarbonisation Future
Jul 2019
Publication
Considering the targets of the Paris agreement rapid decarbonisation of the power system is needed. In order to study cost-optimal and reliable zero and negative carbon power systems a power system model of Western Europe for 2050 is developed. Realistic future technology costs demand levels and generator flexibility constraints are considered. The optimised portfolios are tested for both favourable and unfavourable future weather conditions using results from a global climate model accounting for the potential impacts of climate change on Europe’s weather. The cost optimal mix for zero or negative carbon power systems consists of firm low-carbon capacity intermittent renewable energy sources and flexibility capacity. In most scenarios the amount of low-carbon firm capacity is around 75% of peak load providing roughly 65% of the electricity demand. Furthermore it is found that with a high penetration of intermittent renewable energy sources a high dependence on cross border transmission batteries and a shift to new types of ancillary services is required to maintain a reliable power system. Despite relatively small changes in the total generation from intermittent renewable energy sources between favourable and unfavourable weather years of 6% emissions differ up to 70 MtCO2 yr−1 and variable systems costs up to 25%. In a highly interconnected power system with significant flexible capacity in the portfolio and minimal curtailment of intermittent renewables the potential role of green hydrogen as a means of electricity storage appears to be limited.
Numerical Investigation of Dual Fuel Combustion on a Compression Ignition Engine Fueled with Hydrogen/Natural Gas Blends
Mar 2022
Publication
The present work aims to assess the influence of the composition of blends of hydrogen (H2 ) and Natural Gas (NG) on Dual Fuel (DF) combustion characteristics including gaseous emissions. The 3D-CFD study is carried out by means of a customized version of the KIVA-3V code. An automotive 2.8 L 4-cylinder turbocharged diesel engine was previously modified in order to operate in DF NG–diesel mode and tested at the dynamometer bench. After validation against experimental results the numerical model is applied to perform a set of combustion simulations at 3000 rpm–BMEP = 8 bar in DF H2/NG-diesel mode. Different H2–NG blends are considered: as the H2 mole fraction varies from 0 vol% to 50 vol% the fuel energy within the premixed charge is kept constant. The influence of the diesel Start Of Injection (SOI) is also investigated. Simulation results demonstrate that H2 enrichment accelerates the combustion process and promotes its completion strongly decreasing UHC and CO emissions. Evidently CO2 specific emissions are also reduced (up to about 20% at 50 vol% of H2 ). The main drawbacks of the faster combustion include an increase of in-cylinder peak pressure and pressure rate rise and of NOx emissions. However the study demonstrates that the optimization of diesel SOI can eliminate all aforementioned shortcomings.
Hydrogen Internal Combustion Engine Vehicles: A Review
Nov 2022
Publication
Motor vehicles are the backbone of global transport. In recent years due to the rising costs of fossil fuels and increasing concerns about their negative impact on the natural environment the development of low-emission power supply systems for vehicles has been observed. In order to create a stable and safe global transport system an important issue seems to be the diversification of propulsion systems for vehicles which can be achieved through the simultaneous development of conventional internal combustion vehicles electric vehicles (both battery and fuel cell powered) as well as combustion hydrogen-powered vehicles. This publication presents an overview of commercial vehicles (available on the market) powered by internal combustion hydrogen engines. The work focuses on presenting the development of technology from the point of view of introducing ready-made hydrogen-powered vehicles to the market or technical solutions enabling the use of hydrogen mixtures in internal combustion engines. The study covers the history of the technology dedicated hydrogen and bi-fuel vehicles and vehicles with an engine powered by a mixture of conventional fuels and hydrogen. It presents basic technology parameters and solutions introduced by leading vehicle manufacturers in the vehicle market.
Study of the Permeation Flowrate of an Innovative Way to Store Hydrogen in Vehicles
Oct 2021
Publication
With the global warming of the planet new forms of energy are being sought as an alternative to fossil fuels. Currently hydrogen (H2) is seen as a strong alternative for fueling vehicles. However the major challenge in the use of H2 arises from its physical properties. An earlier study was conducted on the storage of H2 used as fuel in road vehicles powered by spark ignition engines or stacks of fuel cells stored under high pressure inside small spheres randomly packed in an envelope tank. Additionally the study evaluated the performance of this new storage system and compared it with other storage systems already applied by automakers in their vehicles. The current study aims to evaluate the H2 leaks from the same storage system when inserted in any road vehicle parked in conventional garages and to show the compliance of these leaks with European Standards provided that an appropriate choice of materials is made. The system’s compliance with safety standards was proved. Regarding the materials of each component of the storage system the best option from the pool of materials chosen consists of aluminum for the liner of the spheres and the envelope tank CFEP for the structural layer of the spheres and Si for the microchip.
Fuel Flexibility of Solid Oxide Fuel Cells
Aug 2021
Publication
One of the major advantages of SOFCs is their high fuel flexibility. Next to natural gas and hydrogen which are today’s most common fuels for SOFC-systems and cell-/stack-testing respectively various other fuels are applicable as well. In the literature a number of promising results show that available fuels as propane butane ammonia gasoline diesel etc. can be applied. Here the performance of an anode supported cell operated in specialized single cell test benches with different gaseous and liquid fuels and reformates thereof is presented. Fuels as ammonia dissolved urea (AddBlueTM) methane/steam and ethanol/water mixtures can directly be fed to the cell whereas propane and diesel require external reforming. It is shown that in case of a stable fuel supply the cell performance with such fuels is similar to that of appropriate mixtures of H2 N2 CO CO2 and steam if the impact of endothermic reforming or decomposition reactions is considered. Even though a stable fuel cell operation with such fuels is possible in a single cell test bench it should be pointed out that an appropriate fuel processing will be mandatory on the system level.
Aspects of an Experimental Study of Hydrogen Use at Automotive Diesel Engine
Feb 2023
Publication
Hydrogen may represents a good alternative fuel that can be used to fuel internal combustion engines in order to ameliorate energetic and emissions performance. The paper presents some experimental aspects registered at hydrogen use to fuel a diesel engine different substitute ratios being use in the area of 18–34% at 40% engine load and speed of 2000 rev/min. The engine is equipped with an open ECU and the control of the cyclic dosses of diesel fuel and hydrogen are adjusted in order to maintain the engine power performance. The in-cylinder pressure diagrams show the increase of the maximum pressure with 17% from 78.5 bar to 91.8 bar for the maximum substitute ratio. Also values of maximum pressure rise rate start to increase for hydrogen addition in correlation with the increase of fuel amount burned into the premixed stage without exceed the normal values with assure the normal and reliable engine operation. Higher Lower Heating Value and combustion speed of hydrogen assure the increase in thermal efficiency the brake specific energy consumption decreases with 5.4%–7.8% at substitute ratios of 20–27%. The CO2 emission level decreases with 20% for maximum hydrogen cyclic dose. In terms of pollutant emission level at hydrogen use the emission level of the NOx decreases with 50% and the smoke number decreases with 73.8% comparative to classic fuelling at the maximum hydrogen cyclic dose.
A Critical Review of Polymer Electrolyte Membrane Fuel Cell Systems for Automotive Applications: Components, Materials, and Comparative Assessment
Mar 2023
Publication
The development of innovative technologies based on employing green energy carriers such as hydrogen is becoming high in demand especially in the automotive sector as a result of the challenges associated with sustainable mobility. In the present review a detailed overview of the entire hydrogen supply chain is proposed spanning from its production to storage and final use in cars. Notably the main focus is on Polymer Electrolyte Membrane Fuel Cells (PEMFC) as the fuel-cell type most typically used in fuel cell electric vehicles. The analysis also includes a cost assessment of the various systems involved; specifically the materials commonly employed to manufacture fuel cells stacks and hydrogen storage systems are considered emphasizing the strengths and weaknesses of the selected strategies together with assessing the solutions to current problems. Moreover as a sought-after parallelism a comparison is also proposed and discussed between traditional diesel or gasoline cars battery-powered electric cars and fuel cell electric cars thus highlighting the advantages and main drawbacks of the propulsion systems currently available on the market.
Power-to-X in Energy Hubs: A Danish Case Study of Renewable Fuel Production
Feb 2023
Publication
The European Commission recently proposed requirements for the production of renewable fuels as these are required to decarbonize the hard-to-electrify parts of the industrial and heavy transport sectors. Power-to-X (P2X) energy hubs enable efficient synergies between energy infrastructures production facilities and storage options. In this study we explore the optimal operation of an energy hub by leveraging the flexibility of P2X including hydrogen methanol and ammonia synthesizers by analyzing potential revenue streams such as the day-ahead and ancillary services markets. We propose EnerHub2X a mixed-integer linear program that maximizes the hub’s profit based on current market prices considering the technical constraints of P2X such as unit commitment and non-linear efficiencies. We investigate a representative Danish energy hub and find that without price incentives it mainly sells renewable electricity and produces compressed hydrogen. A sufficient amount of renewable ammonia and methanol is only produced by adding a price premium of about 50% (0.16 e/kg) to the conventional fuel prices. To utilize production efficiently on-site renewable energy sources and P2X must be carefully aligned. We show that renewable power purchase agreements can provide flexibility while complying with the rules set by the European Commission.
Review and Comparison of Worldwide Hydrogen Activities in the Rail Sector with Special Focus on On-board Storage and Refueling Technologies
Aug 2022
Publication
"This paper investigates hydrogen storage and refueling technologies that were used in rail vehicles over the past 20 years as well as planned activities as part of demonstration projects or feasibility studies. Presented are details of the currently available technology and its vehicle integration market availability as well as standardization and research and development activities. A total of 80 international studies corporate announcements as well as vehicle and refueling demonstration projects were evaluated with regard to storage and refueling technology pressure level hydrogen amount and installation concepts inside rolling stock. Furthermore current hydrogen storage systems of worldwide manufacturers were analyzed in terms of technical data.<br/>We found that large fleets of hydrogen-fueled passenger railcars are currently being commissioned or are about to enter service along with many more vehicles on order worldwide. 35 MPa compressed gaseous storage system technology currently dominates in implementation projects. In terms of hydrogen storage requirements for railcars sufficient energy content and range are not a major barrier at present (assuming enough installation space is available). For this reason also hydrogen refueling stations required for 35 MPa vehicle operation are currently being set up worldwide.<br/>A wide variety of hydrogen demonstration and retrofit projects are currently underway for freight locomotive applications around the world in addition to completed and ongoing feasibility studies. Up to now no prevailing hydrogen storage technology emerged especially because line-haul locomotives are required to carry significantly more energy than passenger trains. The 35 MPa compressed storage systems commonly used in passenger trains offer too little energy density for mainline locomotive operation - alternative storage technologies are not yet established. Energy tender solutions could be an option to increase hydrogen storage capacity here."
Economic Analysis of a Hydrogen Power Plant in the Portuguese Electricity Market
Feb 2023
Publication
Hydrogen is regarded as a flexible energy carrier with multiple applications across several sectors. For instance it can be used in industrial processes transports heating and electrical power generation. Green hydrogen produced from renewable sources can have a crucial role in the pathway towards global decarbonization. However the success of green hydrogen production ultimately depends on its economic sustainability. In this context this work evaluates the economic performance of a hydrogen power plant participating in the electricity market and supplying multiple hydrogen consumers. The analysis includes technical and economical details of the main components of the hydrogen power plant. Its operation is simulated using six different scenarios which admit the production of either grey or green hydrogen. The scenarios used for the analysis include data from the Iberian electricity market for the Portuguese hub. An important conclusion is that the combination of multiple services in a hydrogen power plant has a positive effect on its economic performance. However as of today consumers who would wish to acquire green hydrogen would have to be willing to pay higher prices to compensate for the shorter periods of operation of hydrogen power plants and for their intrinsic losses. Nonetheless an increase in green hydrogen demand based on a greater environmental awareness can lead to the need to not only build more of these facilities but also to integrate more services into them. This could promote the investment in hydrogen-related technologies and result in changes in capital and operating costs of key components of these plants which are necessary to bring down production costs.
Dynamic Process Modeling of Topside Systems for Evaluating Power Consumption and Possibilities of Using Wind Power
Dec 2022
Publication
Norwegian offshore wind farms may be able to supply power to offshore oil and gas platforms in the near future thanks to the expeditious development of offshore wind technology. This would result in a reduction in CO2 emissions from oil and gas offshore installations which are currently powered predominantly by gas turbines. The challenge with using wind power is that offshore oil and gas installations require a fairly constant and stable source of power whereas wind power typically exhibits significant fluctuations over time. The purpose of this study is to perform a technical feasibility evaluation of using wind power to supply an offshore oil and gas installation on the basis of dynamic process simulations. Throughout the study only the topside processing system is considered since it is the most energy-intensive part of an oil and gas facility. An offshore field on the Norwegian Continental Shelf is used as a case study. The results indicate that when the processing system operates in steady-state conditions it cannot be powered solely by wind energy and another power source is required to compensate for low wind power generation intervals. An alternative would be to store wind energy during periods of high generation (e.g. by producing hydrogen or ammonia) and use it during periods of low generation. Utilizing energy storage methods wind energy can be continuously used for longer periods of time and provide a suitable constant power source for the studied case. Higher constant power can also be provided by increasing the efficiency of energy recovery and storage processes. Alternatively these two technologies may be integrated with gas turbines if the required storage cannot be provided or higher power is required. It was estimated that the integration of wind energy could result in noticeable reductions in CO2 emissions for the case study. Additionally according to the results the production storage and reuse of hydrogen and ammonia on-site may be viable options for supplying power.
Multi-Time Scale Optimal Scheduling Model of Wind and Hydrogen Integrated Energy System Based on Carbon Trading
Jan 2023
Publication
In the context of carbon trading energy conservation and emissions reduction are the development directions of integrated energy systems. In order to meet the development requirements of energy conservation and emissions reduction in the power grid considering the different responses of the system in different time periods a wind-hydrogen integrated multi-time scale energy scheduling model was established to optimize the energy-consumption scheduling problem of the system. As the scheduling model is a multiobjective nonlinear problem the artificial fish swarm algorithm–shuffled frog leaping algorithm (AFS-SFLA) was used to solve the scheduling model to achieve system optimization. In the experimental test process the Griewank benchmark function and the Rosenbrock function were selected to test the performance of the proposed AFS-SFL algorithm. In the Griewank environment compared to the SFLA algorithm the AFS-SFL algorithm was able to find a feasible solution at an early stage and tended to converge after 110 iterations. The optimal solution was −4.83. In the test of total electric power deviation results at different time scales the maximum deviation of early dispatching was 14.58 MW and the minimum deviation was 0.56 MW. The overall deviation of real-time scheduling was the minimum and the minimum deviation was 0 and the maximum deviation was 1.89 WM. The integrated energy system adopted real-time scale dispatching with good system stability and low-energy consumption. Power system dispatching optimization belongs to the objective optimization problem. The artificial fish swarm algorithm and frog algorithm were innovatively combined to solve the dispatching model which improved the accuracy of power grid dispatching. The research content provides an effective reference for the efficient use of clean and renewable energy.
Design of Gravimetric Primary Standards for Field-testing of Hydrogen Refuelling Stations
Apr 2020
Publication
The Federal Institute of Metrology METAS developed a Hydrogen Field Test Standard (HFTS) that can be used for field verification and calibration of hydrogen refuelling stations. The testing method is based on the gravimetric principle. The experimental design of the HFTS as well as the description of the method are presented here.
Risk Assessment of the Low-carbon Transition of Austria’s Steel and Electricity Sectors
Dec 2018
Publication
To limit global temperature increase below +2°C societies need to reduce greenhouse gas emissions radically within the next few decades. Amongst other mitigation measures this requires transforming process-emission intensive industries towards emission neutrality. One way to this end is the renewables-based electrification of industries. We present results of a recent coproduction process which brought together stakeholders from industry policy administration and science to co-create climate-neutral transition pathways for the steel and electricity sectors in Austria. The results summarized here are the definition of reliable pathways and the identification of associated risks pertaining to pathway implementation including a macro-economic quantification. We find that risks to implementation (barriers) are at least as important as risks of implementation (negative consequences). From the quantitative analysis we find that provided that barriers can be reduced macroeconomic costs of the transition are only moderate and that stakeholders might overestimate risks when neglecting economy-wide feedbacks.
Renewable Electricity for Decarbonisation of Road Transport: Batteries or E-Fuels?
Feb 2023
Publication
Road transport is one of the most energy-consuming and greenhouse gas (GHG) emitting sectors. Progressive decarbonisation of electricity generation could support the ambitious target of road vehicle climate neutrality in two different ways: direct electrification with onboard electro-chemical storage or a change of energy vector with e-fuels. The most promising state-of-the-art electrochemical storages for road transport have been analysed considering current and future technologies (the most promising ones) whose use is assumed to occur within the next 10–15 years. Different e-fuels (e-hydrogen e-methanol e-diesel e-ammonia E-DME and e-methane) and their production pathways have been reviewed and compared in terms of energy density synthesis efficiency and technology readiness level. A final energetic comparison between electrochemical storages and e-fuels has been carried out considering different powertrain architectures highlighting the huge difference in efficiency for these competing solutions. E-fuels require 3–5 times more input energy and cause 3–5 times higher equivalent vehicle CO2 emissions if the electricity is not entirely decarbonised.
A Review of The Methanol Economy: The Fuel Cell Route
Jan 2020
Publication
This review presents methanol as a potential renewable alternative to fossil fuels in the fight against climate change. It explores the renewable ways of obtaining methanol and its use in efficient energy systems for a net zero-emission carbon cycle with a special focus on fuel cells. It investigates the different parts of the carbon cycle from a methanol and fuel cell perspective. In recent years the potential for a methanol economy has been shown and there has been significant technological advancement of its renewable production and utilization. Even though its full adoption will require further development it can be produced from renewable electricity and biomass or CO2 capture and can be used in several industrial sectors which make it an excellent liquid electrofuel for the transition to a sustainable economy. By converting CO2 into liquid fuels the harmful effects of CO2 emissions from existing industries that still rely on fossil fuels are reduced. The methanol can then be used both in the energy sector and the chemical industry and become an all-around substitute for petroleum. The scope of this review is to put together the different aspects of methanol as an energy carrier of the future with particular focus on its renewable production and its use in high-temperature polymer electrolyte fuel cells (HT-PEMFCs) via methanol steam reforming.
Life Cycle Greenhouse Gas Emissions of Alternative Fuels and Powertrains for Medium-duty Trucks: A Singapore Case Study
Mar 2022
Publication
Alternatives to conventional diesel engines in medium/heavy-duty commercial trucks offer promising solutions to decarbonize road freight. We compare the life cycle greenhouse gas (GHG) emissions from diesel battery electric (BEV) and hydrogen fuel cell (FCV) medium-duty urban delivery trucks (gross vehicle weight 3.5 – 7 metric tonnes) in Singapore including the vehicle and fuel production use phase and end-of-life stages. Use phase energy demand was estimated by simulating energy consumption on local real-world driving cycles. BEVs powered by the 2019 electricity mix had up to 11% lower GHG emissions than conventional diesel but doubling battery capacity to meet travel range requirements resulted in up to 12% higher emissions. FCVs using gaseous hydrogen via steam methane reforming achieved 23 – 30% GHG reductions while satisfying range requirements. Efforts in obtaining updated and reliable data on vehicle production remain critical for assessments of emerging technologies and enacting evidence-based policies to decarbonize road freight.
Concept Design and Energy Balance Optimization of a Hydrogen Fuel Cell Helicoptor for Unmanned Aerial Vehicle and Aerotaxi Applications
May 2023
Publication
In the new scenario where the transportation sector must be decarbonized to limit global warming fuel cellpowered aerial vehicles have been selected as a strategic target application to compose part of the urban fleet to minimize road transport congestion and make goods and personal transportation fast and efficient. To address the necessity of clean and efficient urban air transport this work consists of the conceptual development of a lightweight rotary-winged transport vehicle using a hydrogen-based fuel cell propulsion system and the optimization of its energy balance. For that purpose the methods for integrating the coupled aerodynamic and propulsion system sizing and optimization was developed with the aim of designing concepts capable of carrying 0 (unmanned aerial vehicle — Design 1) and 1 (Aerotaxi — Design 2) passengers for a distance of 300 km at a cruise altitude of 500 m with a minimum climbing rate capability of 6 m s−1 at 1000 m. The results show how these designs with the desired performance specifications can be obtained with a vehicle mass ranging from 416 to 648 kg depending on the application and with specific range and endurance respectively within 46.2–47.8 km/kg and 20.4–21.3 min/kg for design 1 and 33.3–33.8 km/kg and 12.5–13.9 min/kg for design 2.
GIS-Based Method for Future Prospect of Energy Supply in Algerian Road Transport Sector Using Solar Roads Technology
May 2019
Publication
This paper aims to investigate the possibility of integration of Electric Vehicles EVs supply’s with electricity and/or hydrogen in the road transport sector and estimate the energy supply derived from solar irradiation by using solar roads technology. The case study is road Est-Oust (road E-O) of Algeria. A Geographic Information System and spatial analysis tools are combined with spatial data and technical models to carry out these calculations. The results of this study demonstrate that solar road panels which are integrated into the road E-O produce over to 804 GWh/year which equivalents to 13778 tons of hydrogen per year.by using FCEVs will saving over then 41.103 liter of fossil fuels (regular gasoline); and reduce GHG emission (CO2) in the transportation sector by 216 tons per year.
Advanced Hydrogen Production through Methane Cracking: A Review
Jul 2015
Publication
Hydrogen is widely produced and used for our day-to-day needs. It has also the potential to be used as fuel for industry or can be used as an energy carrier for stationary power. Hydrogen can be produced by different processes like from fossil fuels (Steam methane reforming coal gasification cracking of natural gas); renewable resources (electrolysis wind etc.); nuclear energy (thermochemical water splitting). In this paper few processes have been discussed briefly. Cracking of methane has been given special emphasis in this review for production of hydrogen. There are mainly two types of cracking non-catalytic and catalytic. Catalytic cracking of methane is governed mainly by finding a suitable catalyst; its generation deactivation activation and filament formation for the adsorption of carbon particles (deposited on metal surface); study of metallic support which helps in finding active sites of the catalyst for the reaction to proceed easily. Non-catalytic cracking of methane is mainly based on thermal cracking. Moreover several thermal cracking processes with their reactor configurations have been discussed.
Preparation, Performance and Challenges of Catalyst Layer for Proton Exchange Membrane Fuel Cell
Nov 2021
Publication
In this paper the composition function and structure of the catalyst layer (CL) of a proton exchange membrane fuel cell (PEMFC) are summarized. The hydrogen reduction reaction (HOR) and oxygen reduction reaction (ORR) processes and their mechanisms and the main interfaces of CL (PEM|CL and CL|MPL) are described briefly. The process of mass transfer (hydrogen oxygen and water) proton and electron transfer in MEA are described in detail including their influencing factors. The failure mechanism of CL (Pt particles CL crack CL flooding etc.) and the degradation mechanism of the main components in CL are studied. On the basis of the existing problems a structure optimization strategy for a high‐performance CL is proposed. The commonly used preparation processes of CL are introduced. Based on the classical drying theory the drying process of a wet CL is explained. Finally the research direction and future challenges of CL are pointed out hoping to provide a new perspective for the design and selection of CL materials and preparation equipment.
Everything About Hydrogen Podcast: What's Brewing in the UK Clean Hydrogen Sector?
Dec 2021
Publication
Chris Jackson is the Founder and CEO of Protium Green Solutions based in London. Protium is a hydrogen energy services company that designs develops finances owns and operates clean hydrogen solutions for clients to achieve net zero energy emissions at their industrial/manufacturing sites. Chris will talk to us about the Protium story and also give us some insight into a major project that Protium recently announced in conjunction Budweiser Brewing Group UK&Ireland to explore the deployment of zero emission green hydrogen at Magor brewery in South Wales one of the largest breweries in the UK. To that end in order to get the full story about this project we are delighted to say that we have yet another great guest on this episode. Tom Brewer who leads Global Environmental Sustainability efforts at AB InBev the parent company of Budweiser Brewing Group will join us for the final segment of the show to talk about how hydrogen fits into AB InBev’s vision of a sustainable future for the company.
The podcast can be found on their website
The podcast can be found on their website
Facile Synthesis of Palladium Phosphide Electrocatalysts and their Activity for the Hydrogen Oxidation, Hydrogen Evolutions, Oxygen Reduction and Formic Acid Oxidation Reactions
Nov 2015
Publication
We demonstrate a new approach for producing highly dispersed supported metal phosphide powders with small particle size improved stability and increased electrocatalytic activity towards some useful reactions. The approach involves a one-step conversion of metal supported on high surface area carbon to the metal phosphide utilising a very simple and scalable synthetic process. We use this approach to produce PdP2 and Pd5P2 particles dispersed on carbon with a particle size of 4.5–5.5 nm by converting a commercially available Pd/C powder. The metal phosphide catalysts were tested for the oxygen reduction hydrogen oxidation and evolution and formic acid oxidation reactions. Compared to the unconverted Pd/C material we find that alloying the P at different levels shifts oxide formation on the Pd to higher potentials leading to greater stability during cycling studies (20% more ECSA retained 5k cycles) and in thermal treatment under air. Hydrogen absorption within the PdP2 and Pd5P2 particles is enhanced. The phosphides compare favourably to the most active catalysts reported to date for formic acid oxidation especially PdP2 and there is a significant decrease in poisoning of the surface compared to Pd alone. The mechanistic changes in the reactions studied are rationalised in terms of increased water activation on the surface phosphorus atoms of the catalyst. One of the catalysts PdP2/C is tested in a fuel cell as anode and cathode catalyst and shows good performance.
Impacts of Load Profiles on the Optimization of Power Management of a Green Building Employing Fuel Cells
Dec 2018
Publication
This paper discusses the performance improvement of a green building by optimization procedures and the influences of load characteristics on optimization. The green building is equipped with a self-sustained hybrid power system consisting of solar cells wind turbines batteries proton exchange membrane fuel cell (PEMFC) electrolyzer and power electronic devices. We develop a simulation model using the Matlab/SimPowerSystemTM and tune the model parameters based on experimental responses so that we can predict and analyze system responses without conducting extensive experiments. Three performance indexes are then defined to optimize the design of the hybrid system for three typical load profiles: the household the laboratory and the office loads. The results indicate that the total system cost was reduced by 38.9% 40% and 28.6% for the household laboratory and office loads respectively while the system reliability was improved by 4.89% 24.42% and 5.08%. That is the component sizes and power management strategies could greatly improve system cost and reliability while the performance improvement can be greatly influenced by the characteristics of the load profiles. A safety index is applied to evaluate the sustainability of the hybrid power system under extreme weather conditions. We further discuss two methods for improving the system safety: the use of sub-optimal settings or the additional chemical hydride. Adding 20 kg of NaBH4 can provide 63 kWh and increase system safety by 3.33 2.10 and 2.90 days for the household laboratory and office loads respectively. In future the proposed method can be applied to explore the potential benefits when constructing customized hybrid power systems.
Performance Estimation of a Downsized SI Engine Running with Hydrogen
Jun 2022
Publication
Hydrogen is a carbon-free fuel that can be produced in many ways starting from different sources. Its use as a fuel in internal combustion engines could be a method of significantly reducing their environmental impact. In spark-ignition (SI) engines lean hydrogen–air mixtures can be burnt. When a gaseous fuel like hydrogen is port-injected in an SI engine working with lean mixtures supercharging becomes very useful in order not to excessively penalize the engine performance. In this work the performance of a turbocharged PFI spark-ignition engine fueled by hydrogen has been investigated by means of 1-D numerical simulations. The analysis focused on the engine behavior both at full and partial load considering low and medium engine speeds (1500 and 3000 rpm). Equivalence ratios higher than 0.35 have been considered in order to ensure acceptable cycle-to-cycle variations. The constraints that ensure the safety of engine components have also been respected. The results of the analysis provide a guideline able to set up the load control strategy of a SI hydrogen engine based on the variation of the air to fuel ratio boost pressure and throttle opening. Furthermore performance and efficiency of the hydrogen engine have been compared to those of the base gasoline engine. At 1500 and 3000 rpm except for very low loads the hydrogen engine load can be regulated by properly combining the equivalence ratio and the boost pressure. At 3000 rpm the gasoline engine maximum power is not reached but for each engine load lean burning allows the hydrogen engine achieving much higher efficiencies than those of the gasoline engine. At full load the maximum power output decreases from 120 kW to about 97 kW but the engine efficiency of the hydrogen engine is higher than that of the gasoline one for each full load operating point.
Recent Developments in High-Performance Nafion Membranes for Hydrogen Fuel Cells Applications
Aug 2021
Publication
As a promising alternative to petroleum fossil energy polymer electrolyte membrane fuel cell has drawn considerable attention due to its low pollution emission high energy density portability and long operation times. Proton exchange membrane (PEM) like Nafion plays an essential role as the core of fuel cell. A good PEM must have satisfactory performance such as high proton conductivity excellent mechanical strength electrochemical stability and suitable for making membrane electrode assemblies (MEA). However performance degradation and high permeability remain the main shortcomings of Nafion. Therefore the development of a new PEM with better performance in some special conditions is greatly desired. In this review we aim to summarize the latest achievements in improving the Nafion performance that works well under elevated temperature or methanol-fueled systems. The methods described in this article can be divided into some categories utilizing hydrophilic inorganic material metal-organic frameworks nanocomposites and ionic liquids. In addition the mechanism of proton conduction in Nafion membranes is discussed. These composite membranes exhibit some desirable characteristics but the development is still at an early stage. In the future revolutionary approaches are needed to accelerate the application of fuel cells and promote the renewal of energy structure.
Research on Economic and Operating Characteristics of Hydrogen Fuel Cell Cars Based on Real Vehicle Tests
Nov 2021
Publication
With the increase of the requirement for the economy of vehicles and the strengthening of the concept of environmental protection the development of future vehicles will develop in the direction of high efficiency and cleanliness and the current power system of vehicles based on traditional fossil fuels will gradually transition to hybrid power. As an essential technological direction for new energy vehicles the development of fuel cell passenger vehicles is of great significance in reducing transportation carbon emissions stabilizing energy supply and maintaining the sustainable development of the automotive industry. To study the fuel economy of a passenger car with the proton exchange membrane fuel cell (PEMFC) during the operating phase two typical PEMFC passenger cars test vehicles A and B were compared and analyzed. The hydrogen consumption and hydrogen emission under two operating conditions namely the different steady-state power and the Chinese Vehicle Driving Conditions-Passenger Car cycle were tested. The test results show the actual hydrogen consumption rates of vehicle A and vehicle B are 9.77 g/kM and 8.28 g/kM respectively. The average hydrogen emission rates for vehicle A and vehicle B are 1.56 g/(kW·h) and 5.40 g/(kW·h) respectively. By comparing the hydrogen purge valve opening time ratio the differences between test vehicles A and B in control strategy hydrogen consumption and emission rate are analyzed. This study will provide reference data for China to study the economics of the operational phase of PEMFC vehicles.
Spatially Resolved Model for Studying Decarbonisation Pathways for Heat Supply and Infrastructure Trade-offs
Jun 2017
Publication
Heat decarbonisation is one of the main challenges of energy system decarbonisation. However existing energy planning models struggle to compare heat decarbonisation approaches because they rarely capture trade-offs between heat supply end-use technologies and network infrastructure at sufficient spatial resolution. A new optimisation model is presented that addresses this by including trade-offs between gas electricity and heat infrastructure together with related supply and end-use technologies with high spatial granularity. The model is applied in case studies for the UK. For the case modelled it is shown that electrification of heat is most cost-effective via district level heat pumps that supply heat networks instead of individual building heat pumps. This is because the cost of reinforcing the electricity grid for installing individual heat pumps does not sufficiently offset heat infrastructure costs. This demonstrates the importance of considering infrastructure trade-offs. When modelling the utilisation of a decarbonised gas the penetration of heat networks and location of district level heat supply technologies was shown to be dependent on linear heat density and on zone topology. This shows the importance of spatial aspects. Scenario-specific linear heat density thresholds for heat network penetration were identified. For the base case penetration of high temperature heat networks was over 50% and 60% by 2050 for linear heat densities over 1500 and 2500 kWh/m. For the case when medium heat temperature networks were additionally available a mix of both networks was observed. Medium temperature heat network penetration was over 20% 30% and 40% for linear heat densities of over 1500 2500 and 3000 kWh/m while high temperature heat network penetration was over 20% and 30% for linear heat densities of under 2000 and 1500 kWh/m respectively.
Conceptual Design of a Hybrid Hydrogen Fuel Cell/Battery Blended-Wing-Body Unmanned Aerial Vehicle—An Overview
May 2022
Publication
The manuscript presents the conceptual design phase of an unmanned aerial vehicle with the objective of a systems approach towards the integration of a hydrogen fuel-cell system and Li-ion batteries into an aerodynamically efficient platform representative of future aircraft configurations. Using a classical approach to aircraft design and a combination of low- and high-resolution computational simulations a final blended wing body UAV was designed with a maximum take-off weight of 25 kg and 4 m wingspan. Preliminary aerodynamic and propulsion sizing demonstrated that the aircraft is capable of completing a 2 h long mission powered by a 650 W fuel cell hybridized with a 100 Wh battery pack and with a fuel quantity of 80 g of compressed hydrogen.
Investigation on System for Renewable Electricity Storage in Small Scale Integrating Photovoltaics, Batteries, and Hydrogen Generator
Nov 2020
Publication
In this article the solution based on hydrogen generation to increase the flexibility of energy storage systems is proposed. Operating characteristics of a hydrogen generator with integrated electrical energy storage and a photovoltaic installation were determined. The key role of the electricity storage in the proposed system was to maintain the highest operating efficiency related to the nominal parameters of the hydrogen generator. The hydrogen generators achieved the highest energy efficiency for the nominal operating point at the highest power output. Lead-acid batteries were used to ensure the optimal operating conditions for the hydrogen generator supplied with renewable energy throughout the day. The proposed system reduces significantly the hydrogen generator nominal power and devices in system operate in such a way to improve their efficiency and durability. The relations between individual components and their constraints were determined. The proposed solution is fully in-line with previously investigated technologies for improving grid stability and can help incorporate renewable energy sources to increase the sustainability of the energy sector and green hydrogen production.
Hydrogen Addition Influence for the Efficient and Ecological Parameters of Heavy-Duty Natural Gas Si Engine
May 2017
Publication
The paper presents the experimental research results of heavy-duty vehicle (public transport bus) fuelled with natural gas and hydrogen fuel mixtures. Spark ignition six cylinder engine tested with different hydrogen additions (from 5% up to 20% according to volume) in the natural gas fuel. The tests were performed on heavy-duty vehicle’s dyno test stand in company “SG dujos Auto” research laboratory. The tests were carried out at three load points and one engine speed. Engine had originally a port fuel injection and exhaust gas recirculation system. Experiments showed that engine fuelled with hydrogen addition was able to achieve lower fuel consumption and brake specific fuel consumption. It was also possible to achieve small increase of engine efficiency. The exhaust gas measurements showed that hydrogen addition in natural gas reduced the CO CO2 and HC emissions because of the H/C atom ratio change in fuel mixture and improved combustion process. The NOx emission level was decreasing although bigger amounts of hydrogen were used in natural gas fuel.
Integrating Housing Stock and Energy System Models as a Strategy to Improve Heat Decarbonisation Assessments
Aug 2014
Publication
The UK government heat strategy is partially based on decarbonisation pathways from the UK MARKAL energy system model. We review how heat provision is represented in UK MARKAL identifying a number of shortcomings and areas for improvement. We present a completely revised model with improved estimations of future heat demands and a consistent representation of all heat generation technologies. This model represents all heat delivery infrastructure for the first time and uses dynamic growth constraints to improve the modelling of transitions according to innovation theory. Our revised model incorporates a simplified housing stock model which is used produce highly-refined decarbonisation pathways for residential heat provision. We compare this disaggregated model against an aggregated equivalent which is similar to the existing approach in UK MARKAL. Disaggregating does not greatly change the total residential fuel consumption in two scenarios so the benefits of disaggregation will likely be limited if the focus of a study is elsewhere. Yet for studies of residential heat disaggregation enables us to vary consumer behaviour and government policies on different house types as well as highlighting different technology trends across the stock in comparison with previous aggregated versions of the model.
Performance of Common Rail Direct Injection (CRDi) Engine Using Ceiba Pentandra Biodiesel and Hydrogen Fuel Combination
Nov 2021
Publication
An existing diesel engine was fitted with a common rail direct injection (CRDi) facility to inject fuel at higher pressure in CRDi mode. In the current work rotating blades were incorporated in the piston cavity to enhance turbulence. Pilot fuels used are diesel and biodiesel of Ceiba pentandra oil (BCPO) with hydrogen supply during the suction stroke. Performance evaluation and emission tests for CRDi mode were carried out under different loading conditions. In the first part of the work maximum possible hydrogen substitution without knocking was reported at an injection timing of 15◦ before top dead center (bTDC). In the second part of the work fuel injection pressure (IP) was varied with maximum hydrogen fuel substitution. Then in the third part of the work exhaust gas recirculation (EGR) was varied to study the nitrogen oxides (NOx) generated. At 900 bar HC emissions in the CRDi engine were reduced by 18.5% and CO emissions were reduced by 17% relative to the CI mode. NOx emissions from the CRDi engine were decreased by 28% relative to the CI engine mode. At 20% EGR lowered the BTE by 14.2% and reduced hydrocarbons nitrogen oxide and carbon monoxide by 6.3% 30.5% and 9% respectively compared to the CI mode of operation.
Design and Analysis of an Offshore Wind Power to Ammonia Production System in Nova Scotia
Dec 2022
Publication
Green ammonia has potential as a zero-emissions energy vector in applications such as energy storage transmission and distribution and zero-emissions transportation. Renewable energy such as offshore wind energy has been proposed to power its production. This paper designed and analyzed an on-land small-scale power-to-ammonia (P2A) production system with a target nominal output of 15 tonnes of ammonia per day which will use an 8 MW offshore turbine system off the coast of Nova Scotia Canada as the main power source. The P2A system consists of a reverse osmosis system a proton exchange membrane (PEM) electrolyser a hydrogen storage tank a nitrogen generator a set of compressors and heat exchangers an autothermal Haber-Bosch reactor and an ammonia storage tank. The system uses an electrical grid as a back-up for when the wind energy is insufficient as the process assumes a steady state. Two scenarios were analyzed with Scenario 1 producing a steady state of 15 tonnes of ammonia per day and Scenario 2 being one that switched production rates whenever wind speeds were low to 55% the nominal capacity. The results show that the grid connected P2A system has significant emissions for both scenarios which is larger than the traditional fossil-fuel based ammonia production when using the grid in provinces like Nova Scotia even if it is just a back-up during low wind power generation. The levelized cost of ammonia (LCOA) was calculated to be at least 2323 CAD tonne−1 for both scenarios which is not cost competitive in this small production scale. Scaling up the whole system reducing the reliance on the electricity grid increasing service life and decreasing windfarm costs could reduce the LCOA and make this P2A process more cost competitive.
Mapping Australia's Hydrogen Future and release of the Hydrogen Economic Fairways Tool
Apr 2021
Publication
Hydrogen can be used for a variety of domestic and industrial purposes such as heating and cooking (as a replacement for natural gas) transportation (replacing petrol and diesel) and energy storage (by converting intermittent renewable energy into hydrogen). The key benefit of using hydrogen is that it is a clean fuel that emits only water vapour and heat when combusted.
To support implementation of the National Hydrogen Strategy Geoscience Australia in collaboration with Monash University are releasing the Hydrogen Economic Fairways Tool (HEFT). HEFT is a free online tool designed to support decision making by policymakers and investors on the location of new infrastructure and development of hydrogen hubs in Australia. It considers both hydrogen produced from renewable energy and from fossil fuels with carbon capture and storage.
This seminar demonstrates HEFT’s capabilities its potential to attract worldwide investment into Australia’s hydrogen industry and what’s up next for hydrogen at Geoscience Australia.
You can use the Hydrogen Economic Fairways Tool (HEFT) on the Website of the Australian government at the link here
To support implementation of the National Hydrogen Strategy Geoscience Australia in collaboration with Monash University are releasing the Hydrogen Economic Fairways Tool (HEFT). HEFT is a free online tool designed to support decision making by policymakers and investors on the location of new infrastructure and development of hydrogen hubs in Australia. It considers both hydrogen produced from renewable energy and from fossil fuels with carbon capture and storage.
This seminar demonstrates HEFT’s capabilities its potential to attract worldwide investment into Australia’s hydrogen industry and what’s up next for hydrogen at Geoscience Australia.
You can use the Hydrogen Economic Fairways Tool (HEFT) on the Website of the Australian government at the link here
Decarbonization of Australia’s Energy System: Integrated Modelling of the Transformation of Electricity, Transportation, and Industrial Sectors
Jul 2020
Publication
To achieve the Paris Agreement’s long-term temperature goal current energy systems must be transformed. Australia represents an interesting case for energy system transformation modelling: with a power system dominated by fossil fuels and specifically with a heavy coal component there is at the same time a vast potential for expansion and use of renewables. We used the multi-sectoral Australian Energy Modelling System (AUSeMOSYS) to perform an integrated analysis of implications for the electricity transport and selected industry sectors to the mid-century. The state-level resolution allows representation of regional discrepancies in renewable supply and the quantification of inter-regional grid extensions necessary for the physical integration of variable renewables. We investigated the impacts of different CO2 budgets and selected key factors on energy system transformation. Results indicate that coal-fired generation has to be phased out completely by 2030 and a fully renewable electricity supply achieved in the 2030s according to the cost-optimal pathway implied by the 1.5 °C Paris Agreement-compatible carbon budget. Wind and solar PV can play a dominant role in decarbonizing Australia’s energy system with continuous growth of demand due to the strong electrification of linked energy sectors.
Drivers and Barriers to the Adoption of Fuel Cell Passenger Vehicles and Buses in Germany
Feb 2021
Publication
As policymakers and automotive stakeholders around the world seek to accelerate the electrification of road transport with hydrogen this study focuses on the experiences of Germany a world leader in fuel cell technology. Specifically it identifies and compares the drivers and barriers influencing the production and market penetration of privately-owned fuel cell electric passenger vehicles (FCEVs) and fuel cell electric buses (FCEBs) in public transit fleets. Using original data collected via a survey and 17 interviews we elicited the opinions of experts to examine opportunities and obstacles in Germany from four perspectives: (i) the supply of vehicles (ii) refuelling infrastructure (iii) demand for vehicles and (iv) cross-cutting institutional issues. Findings indicate that despite multiple drivers there are significant challenges hampering the growth of the hydrogen mobility market. Several are more pronounced in the passenger FCEV market. These include the supply and cost of production the lack of German automakers producing FCEVs the profitability and availability of refuelling stations and low demand for vehicles. In light of these findings we extract implications for international policymakers and future studies. This study provides a timely update on efforts to spur the deployment of hydrogen mobility in Germany and addresses the underrepresentation of studies examining both buses and passenger vehicles in tandem.
Performance Analysis of a Flexi-Fuel Turbine-Combined Free-Piston Engine Generator
Jul 2019
Publication
The turbine-combined free-piston engine generator (TCFPEG) is a hybrid machine generating both mechanical work from the gas turbine and electricity from the linear electric generator for battery charging. In the present study the system performance of the designed TCFPEG system is predicted using a validated numerical model. A parametric analysis is undertaken based on the influence of the engine load valve timing the number of linear generators adopted and different fuels on the system performance. It is found that when linear electric generators are connected with the free-piston gas turbine the bottom dead centre the peak piston velocity and engine operation frequency are all reduced. Very minimal difference on the in-cylinder pressure and the compressor pressure is observed while the peak pressure in the bounce chamber is reduced. When coupled with a linear electric generator the system efficiency can be improved to nearly 50% by optimising engine load and the number of the linear generators adopted in the TCFPEG system. The system is able to be operated with different fuels as the piston is not limited by a mechanical system; the output power and system efficiency are highest when hydrogen is used as the fuel.
Hydrogen Fuel Cell Vehicles; Current Status and Future Prospect
Jun 2019
Publication
The hazardous effects of pollutants from conventional fuel vehicles have caused the scientific world to move towards environmentally friendly energy sources. Though we have various renewable energy sources the perfect one to use as an energy source for vehicles is hydrogen. Like electricity hydrogen is an energy carrier that has the ability to deliver incredible amounts of energy. Onboard hydrogen storage in vehicles is an important factor that should be considered when designing fuel cell vehicles. In this study a recent development in hydrogen fuel cell engines is reviewed to scrutinize the feasibility of using hydrogen as a major fuel in transportation systems. A fuel cell is an electrochemical device that can produce electricity by allowing chemical gases and oxidants as reactants. With anodes and electrolytes the fuel cell splits the cation and the anion in the reactant to produce electricity. Fuel cells use reactants which are not harmful to the environment and produce water as a product of the chemical reaction. As hydrogen is one of the most efficient energy carriers the fuel cell can produce direct current (DC) power to run the electric car. By integrating a hydrogen fuel cell with batteries and the control system with strategies one can produce a sustainable hybrid car
Review of the Hydrogen Permeability of the Liner Material of Type IV On-Board Hydrogen Storage Tank
Aug 2021
Publication
The hydrogen storage tank is a key parameter of the hydrogen storage system in hydrogen fuel cell vehicles (HFCVs) as its safety determines the commercialization of HFCVs. Compared with other types the type IV hydrogen storage tank which consists of a polymer liner has the advantages of low cost lightweight and low storage energy consumption but meanwhile higher hydrogen permeability. A detailed review of the existing research on hydrogen permeability of the liner material of type IV hydrogen storage tanks can improve the understanding of the hydrogen permeation mechanism and provide references for following-up researchers and research on the safety of HFCVs. The process of hydrogen permeation and test methods are firstly discussed in detail. This paper then analyzes the factors that affect the process of hydrogen permeation and the barrier mechanism of the liner material and summarizes the prediction models of gas permeation. In addition to the above analysis and comments future research on the permeability of the liner material of the type IV hydrogen storage tank is prospected.
Hydrogen for Transport Prospective Australian Use Cases
Oct 2019
Publication
The Australian transport sector is under increasing pressure to reduce carbon emissions whilst also managing a fuel supply chain that relies heavily on foreign import partners.
Transport in Australia equates to a significant proportion (approximately 18%) of the country’s total greenhouse gas emissions. Due to ongoing population growth these emissions have been steadily rising with the increase of cars on our roads and freight trucks in transit. Coupled with this the transport fuel supply chain is highly reliant on overseas partners – Australia currently imports 90% of its liquid fuel. These two challenges present an interesting dichotomy for the industry incentivising research and development into new technologies that can address one or both of these issues.
Hydrogen is one technology that has the potential to provide a reduction in greenhouse gas emissions as well as a more reliable domestic fuel supply. Hydrogen fuel cell electric vehicles (FCEVs) are an emerging zero-emission alternative for the transport sector which offer a variety of benefits.
You can read the full report on the Aurecon Australasia website at this link
Transport in Australia equates to a significant proportion (approximately 18%) of the country’s total greenhouse gas emissions. Due to ongoing population growth these emissions have been steadily rising with the increase of cars on our roads and freight trucks in transit. Coupled with this the transport fuel supply chain is highly reliant on overseas partners – Australia currently imports 90% of its liquid fuel. These two challenges present an interesting dichotomy for the industry incentivising research and development into new technologies that can address one or both of these issues.
Hydrogen is one technology that has the potential to provide a reduction in greenhouse gas emissions as well as a more reliable domestic fuel supply. Hydrogen fuel cell electric vehicles (FCEVs) are an emerging zero-emission alternative for the transport sector which offer a variety of benefits.
You can read the full report on the Aurecon Australasia website at this link
Integrated Energy System Powered a Building in Sharjah Emirates in the United Arab Emirates
Jan 2023
Publication
In this study a green hydrogen system was studied to provide electricity for an office building in the Sharjah emirate in the United Arab Emirates. Using a solar PV a fuel cell a diesel generator and battery energy storage; a hybrid green hydrogen energy system was compared to a standard hybrid system (Solar PV a diesel generator and battery energy storage). The results show that both systems adequately provided the power needed for the load of the office building. The cost of the energy for both the basic and green hydrogen energy systems was 0.305 USD/kWh and 0.313 USD/kWh respectively. The cost of the energy for both systems is very similar even though the capital cost of the green hydrogen energy system was the highest value; however the replacement and operational costs of the basic system were higher in comparison to the green hydrogen energy system. Moreover the impact of the basic system in terms of the carbon footprint was more significant when compared with the green hydrogen system. The reduction in carbon dioxide was a 4.6 ratio when compared with the basic system.
A Review of Decarbonization Options for the Glass Industry
May 2021
Publication
The glass industry is part of the energy-intensive industry posing a major challenge to fulfill the CO2 reduction targets of the Paris Climate Agreement. The segments of the glass industry e.g. container or flat glass are quite diverse and attribute to different glass products with different requirements to product quality and various process options. To address the challenge of decarbonizing the glass industry firstly an inventory of current glass products processes and applied technologies in terms of energy efficiency and CO2 emissions is conducted. Secondly decarbonization options are identified and structured according to fuel substitution waste heat recovery and process intensification. Due to the high share of energy-related CO2 emissions electrical melting and hydrogen combustion or a combination of both are the most promising options to decarbonize the glass industry but further research design adjustments and process improvements are necessary. Furthermore electricity and hydrogen prices have to decrease or fossil fuels must become more expensive to be cost-competitive relative to fossil fuels and respective infrastructures have to be constructed or adjusted. Various heat recovery options have great potential for CO2 savings but can be technically challenging or have not yet been considered for techno-economic reasons.
Integration Design and Operation Strategy of Multi-Energy Hybrid System Including Renewable Energies, Batteries and Hydrogen
Oct 2020
Publication
In some areas the problem of wind and solar power curtailment is prominent. Hydrogen energy has the advantage of high storage density and a long storage time. Multi-energy hybrid systems including renewable energies batteries and hydrogen are designed to solve this problem. In order to reduce the power loss of the converter an AC-DC hybrid bus is proposed. A multi-energy experiment platform is established including a wind turbine photovoltaic panels a battery an electrolyzer a hydrogen storage tank a fuel cell and a load. The working characteristics of each subsystem are tested and analyzed. The multi-energy operation strategy is based on state monitoring and designed to enhance hydrogen utilization energy efficiency and reliability of the system. The hydrogen production is guaranteed preferentially and the load is reliably supplied. The system states are monitored such as the state of charge (SOC) and the hydrogen storage level. The rated and ramp powers of the battery and fuel cell and the pressure limit of the hydrogen storage tank are set as safety constraints. Eight different operation scenarios comprehensively evaluate the system’s performance and via physical experiments the proposed operation strategy of the multi-energy system is verified as effective and stable.
Life Cycle Inventory Data Generation by Process Simulation for Conventional, Feedstock Recycling and Power-to-X Technologies for Base Chemical Production
Jan 2022
Publication
The article presents the methodology and applicable data for the generation of life cycle inventory for conventional and alternative processes for base chemical production by process simulation. Addressed base chemicals include lower olefins BTX aromatics methanol ammonia and hydrogen. Assessed processes include conventional chemical production processes from naphtha LPG natural gas and heavy fuel oil; feedstock recycling technologies via gasification and pyrolysis of refuse derived fuel; and power-to-X technologies from hydrogen and CO2. Further process variations with additional hydrogen input are covered. Flowsheet simulation in Aspen Plus is applied to generate datasets with conclusive mass and energy balance under uniform modelling and assessment conditions with available validation data. Process inventory data is generated with no regard to the development stage of the respective technology but applicable process data with high technology maturity is prioritized for model validation. The generated inventory data can be applied for life cycle assessments. Further the presented modelling and balancing framework can be applied for inventory data generation of similar processes to ensure comparability in life cycle inventory data.
Systematic Overview of Newly Available Technologies in the Green Maritime Sector
Jan 2023
Publication
The application of newly available technologies in the green maritime sector is difficult due to conflicting requirements and the inter-relation of different ecological technological and economical parameters. The governments incentivize radical reductions in harmful emissions as an overall priority. If the politics do not change the continuous implementation of stricter government regulations for reducing emissions will eventually result in the mandatory use of what we currently consider alternative fuels. Immediate application of radically different strategies would significantly increase the economic costs of maritime transport thus jeopardizing its greatest benefit: the transport of massive quantities of freight at the lowest cost. Increased maritime transport costs would immediately disrupt the global economy as seen recently during the COVID-19 pandemic. For this reason the industry has shifted towards a gradual decrease in emissions through the implementation of “better” transitional solutions until alternative fuels eventually become low-cost fuels. Since this topic is very broad and interdisciplinary our systematic overview gives insight into the state-of-the-art available technologies in green maritime transport with a focus on the following subjects: (i) alternative fuels; (ii) hybrid propulsion systems and hydrogen technologies; (iii) the benefits of digitalization in the maritime sector aimed at increasing vessel efficiency; (iv) hull drag reduction technologies; and (v) carbon capture technologies. This paper outlines the challenges advantages and disadvantages of their implementation. The results of this analysis elucidate the current technologies’ readiness levels and their expected development over the coming years.
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