Institution of Gas Engineers & Managers
A Power Dispatch Allocation Strategy to Produce Green Hydrogen in a Grid-integrated Offshore Hybrid Energy System
Mar 2024
Publication
A dedicated grid-tied offshore hybrid energy system for hydrogen production is a promising solution to unlock the full benefit of offshore wind and solar energy and realize decarbonization and sustainable energy security targets in electricity and other sectors. Current knowledge of these offshore hybrid systems is limited particularly in the integration component control and allocation aspects. Therefore a grid-integrated analytical model with a power dispatch allocation strategy between the grid and electrolyzer for the co-production of hydrogen from the offshore hybrid energy system is developed in this paper. While producing hydrogen the proposed offshore hybrid energy system supplies a percentage of its capacity to the onshore grid facility and the amount of the electricity is quantified based on the electricity market price and available total offshore generation. The detailed controls of each component are discussed. A case study considers a hypothetical hybrid offshore energy system of 10 MW situated in a potential offshore off the NSW of Australia based on realistic metrological data. A grid-scale proton-exchange membrane electrolyzer stack is used and a model predictive power controller is implemented on the distributed hydrogen generation scheme. The model is helpful for the assessment or optimization of both the economics and feasibility of the dedicated offshore hybrid energy farm for hydrogen production systems.
Novel Use of Green Hydrogen Fuel Cell-Based Combined Heat and Power Systems to Reduce Primary Energy Intake and Greenhouse Emissions in the Building Sector
Feb 2021
Publication
Achieving European climate neutrality by 2050 requires further efforts not only from the industry and society but also from policymakers. The use of high-efficiency cogeneration facilities will help to reduce both primary energy consumption and CO2 emissions because of the increase in overall efficiency. Fuel cell-based cogeneration technologies are relevant solutions to these points for small- and microscale units. In this research an innovative and new fuel cell-based cogeneration plant is studied and its performance is compared with other cogeneration technologies to evaluate the potential reduction degree in energy consumption and CO2 emissions. Four energy consumption profile datasets have been generated from real consumption data of different dwellings located in the Mediterranean coast of Spain to perform numerical simulations in different energy scenarios according to the fuel used in the cogeneration. Results show that the fuel cell-based cogeneration systems reduce primary energy consumption and CO2 emissions in buildings to a degree that depends on the heat-to-power ratio of the consumer. Primary energy consumption varies from 40% to 90% of the original primary energy consumption when hydrogen is produced from natural gas reforming process and from 5% to 40% of the original primary energy consumption if the cogeneration is fueled with hydrogen obtained from renewable energy sources. Similar reduction degrees are achieved in CO2 emissions.
Optimal Planning of Hybrid Electricity–Hydrogen Energy Storage System Considering Demand Response
Mar 2023
Publication
In recent years the stability of the distribution network has declined due to the large proportion of the uses of distributed generation (DG) with the continuous development of renewable energy power generation technology. Meanwhile the traditional distribution network operation mode cannot keep the balance of the source and load. The operation mode of the active distribution network (ADN) can effectively reduce the decline in operation stability caused by the high proportion of DG. Therefore this work proposes a bi-layer model for the planning of the electricity–hydrogen hybrid energy storage system (ESS) considering demand response (DR) for ADN. The upper layer takes the minimum load fluctuation maximum user purchase cost satisfaction and user comfort as the goals. Based on the electricity price elasticity matrix model the optimal electricity price formulation strategy is obtained for the lower ESS planning. In the lower layer the optimal ESS planning scheme is obtained with the minimum life cycle cost (LCC) of ESS the voltage fluctuation of ADN and the load fluctuation as the objectives. Finally the MOPSO algorithm is used to test the model and the correctness of the proposed method is verified by the extended IEEE-33 node test system. The simulation results show that the fluctuation in the voltage and load is reduced by 62.13% and 37.06% respectively.
Methane Cracking for Hydrogen Production: A Review of Catalytic and Molten Media Pyrolysis
May 2022
Publication
Currently hydrogen is mainly generated by steam methane reforming with significant CO2 emissions thus exacerbating the greenhouse effect. This environmental concern promotes methane cracking which represents one of the most promising alternatives for hydrogen production with theoretical zero CO/CO2 emissions. Methane cracking has been intensively investigated using metallic and carbonaceous catalysts. Recently research has focused on methane pyrolysis in molten metals/salts to prevent both reactor coking and rapid catalyst deactivation frequently encountered in conventional pyrolysis. Another expected advantage is the heat transfer improvement due to the high heat capacity of molten media. Apart from the reaction itself that produces hydrogen and solid carbon the energy source used in this endothermic process can also contribute to reducing environmental impacts. While most researchers used nonrenewable sources based on fossil fuel combustion or electrical heating concentrated solar energy has not been thoroughly investigated to date for pyrolysis in molten media. However it could be a promising innovative pathway to further improve hydrogen production sustainability from methane cracking. After recalling the basics of conventional catalytic methane cracking and the developed solar cracking reactors this review delves into the most significant results of the state-of-the-art methane pyrolysis in melts (molten metals and salts) to show the advantages and the perspectives of this new path as well as the carbon products’ characteristics and the main factors governing methane conversion.
Numerical Characterization of Under-expanded Cryogenic Hydrogen Gas Jets
Sep 2022
Publication
High-resolution direct numerical simulations are conducted for under-expanded cryogenic hydrogen gas jets to characterize the nearfield flow physics. The basic flow features and jet dynamics are analyzed in detail revealing the existence of four stages during early jet development namely (a) initial penetration (b) establishment of near-nozzle expansion (c) formation of downstream compression and (d) wave propagation. Complex acoustic waves are formed around the under-expanded jets. The jet expansion can also lead to conditions for local liquefaction from the pressurized cryogenic hydrogen gas release. A series of simulations are conducted with systematically varied nozzle pressure ratios and systematically changed exit diameters. The acoustic waves around the jets are found to waken with the decrease in the nozzle pressure ratio. The increase in the nozzle pressure ratio is found to accelerate hydrogen dispersion and widen the regions with hydrogen liquefaction potential. The increase in the nozzle exit diameter also widens the region with hydrogen liquefaction potential but slows down the evolution of the flow structures.
Metallic Materials for Hydrogen Storage—A Brief Overview
Nov 2022
Publication
The research and development of materials suitable for hydrogen storage has received a great deal of attention worldwide. Due to the safety risks involved in the conventional storage of hydrogen in its gaseous or liquid phase in containers and tanks development has focused on solid-phase hydrogen storage including metals. Light metal alloys and high-entropy alloys which have a high potential for hydrogen absorption/desorption at near-standard ambient conditions are receiving interest. For the development of these alloys due to the complexity of their compositions a computational approach using CALPHAD (Calculation of Phases Diagrams) and machine learning (ML) methods that exploit thermodynamic databases of already-known and experimentally verified systems are being increasingly applied. In order to increase the absorption capacity or to decrease the desorption temperature and to stabilize the phase composition specific material preparation methods (HEBM—high-energy milling HPT—high-pressure torsion) referred to as activation must be applied for some alloys.
Review of Hydrogen-Gasoline SI Dual Fuel Engines: Engine Performance and Emission
Mar 2023
Publication
Rapid depletion of conventional fossil fuels and increasing environmental concern are demanding an urgent carry out for research to find an alternate fuel which meets the fuel demand with minimum environmental impacts. Hydrogen is considered as one of the important fuel in the near future which meets the above alarming problems. Hydrogen–gasoline dual fuel engines use hydrogen as primary fuel and gasoline as secondary fuel. In this review paper the combustion performance emission and cyclic variation characteristics of a hydrogen–gasoline dual fuel engine have been critically analyzed. According to scientific literature hydrogen–gasoline dual fuel engines have a good thermal efficiency at low and partial loads but the performance deteriorates at high loads. Hydrogen direct injection with gasoline port fuel injection is the optimum configuration for dual fuel engine operating on hydrogen and gasoline. This configuration shows superior result in mitigating the abnormal combustion but experiences high NOx emission. Employing EGR showed a maximum reduction of 77.8% of NOx emission with a EGR flowrate of 18% further increment in flowrate leads to combustion instability. An overview on hydrogen production and carbon footprint related with hydrogen production is also included. This review paper aims to provide comprehensive findings from past works associated with hydrogen–gasoline dual fuel approach in a spark ignition engine
The Cost Reduction Analysis of Green Hydrogen Production from Coal Mine Underground Water for Circular Economy
May 2024
Publication
The novelty of the paper is the analysis of the possibilities of reducing the operating costs of a mine water pumping station in an abandoned coal mine. To meet the energy needs of the pumping station and reduce the carbon footprint “green” energy from a photovoltaic farm was used. Surplus green energy generated during peak production is stored in the form of green hydrogen from the water electrolysis process. Rainwater and process water are still underutilized sources for increasing water resources and reducing water stress in the European Union. The article presents the possibilities of using these waters after purification in the production of green hydrogen by electrolysis. The article also presents three variants that ensure the energy self-sufficiency of the proposed concepts of operation of the pumping station.
Green Hydrogen Driven by Wind and Solar—An Australian Case Study
Apr 2024
Publication
The energy transition to wind and solar opens up opportunities for green hydrogen as wind and solar generation tend to bring electricity prices down to very low levels. We evaluate whether green hydrogen can integrate well with wind and solar PVs to improve the South Australian electricity grid. Green hydrogen can use membrane electrolysis plants during periods of surplus renewable energy. This hydrogen can then be electrified or used in industry. The green hydrogen system was analysed to understand the financial viability and technical impact of integrating green hydrogen. We also used system engineering techniques to understand the system holistically including the technical social environmental and economic impacts. The results show opportunities for the system to provide seasonal storage grid firming and reliability services. Financially it would need changes to electricity rules to be viable so at present it would not be viable without subsidy.
The Vision of France, Germany, and the European Union on Future Hydrogen Energy Research and Innovation
Jul 2021
Publication
Hydrogen (H2) is an essential vector for freeing our societies from fossil fuels and effectively initiating the energy transition. Offering high energy density hydrogen can be used for mobile stationary or industrial applications of all sizes. This perspective on the crucial role of hydrogen is shared by a growing number of countries worldwide (e.g. China Germany Japan Republic of Korea Australia and United States) which are publishing ambitious roadmaps for the development of hydrogen and fuel cell technologies supported by substantial financial efforts.
Review on COx-free Hydrogen from Methane Cracking: Catalysts, Solar Energy Integration and Applications
Oct 2021
Publication
Hydrogen fuel production from methane cracking is a sustainable process compared to the ones currently in practice due to minimal greenhouse gas emissions. Carbon black that is co-produced is a valuable product and can be marketed to other industries. As this is a high-temperature process using concentrated solar energy can further improve its sustainability. In this study a detailed review is conducted to study the advancements in methane cracking for hydrogen production using different catalysts. Various solar reactors developed for methane cracking are discussed. The application of hydrogen to produce other valuable chemicals are outlined. Hydrogen carriers such as methanol dimethyl ether ammonia and urea can efficiently store hydrogen energy and enable easier transportation. Further research in the field of methane cracking is required for reactor scale-up improved economics and to reduce the problems arising from carbon deposition leading to reactor clogging and catalyst deactivation.
Influence of Hydrogen Enrichment Strategy on Performance Characteristics, Combustion and Emissions of a Rotary Engine for Unmanned Aerial Vehicles (UAVs)
Dec 2022
Publication
In recent years there has been great interest in Wankel-type rotary engines which are one of the most suitable power sources for unmanned aerial vehicle (UAV) applications due to their high power-to-size and power-to-weight ratios. The purpose of the present study was to investigate the potential of a hydrogen enrichment strategy for the improvement of the performance and reduction of the emissions of Wankel engines. The main motivation behind this study was to make Wankel engines which are already very advantageous for UAV applications even more advantageous by applying the hydrogen enrichment technique. In this study hydrogen addition was implemented in a spark-ignition rotary engine model operating at a constant engine speed of 6000 rpm. The mass fraction of hydrogen in the intake gradually increased from 0% to 10%. Simulation results revealed that addition of hydrogen to the fuel accelerated the flame propagation and increased the burning speed of the fuel the combustion temperature and the peak pressure in the working chamber. These phenomena had a very positive effect on the performance and emissions of the Wankel engine. The indicated mean effective pressure (IMEP) increased by 8.18% and 9.68% and the indicated torque increased by 6.15% and 7.99% for the 5% and 10% hydrogen mass fraction cases respectively compared to those obtained with neat gasoline. In contrast CO emissions were reduced by 33.35% and 46.21% and soot emissions by 11.92% and 20.06% for 5% and 10% hydrogen additions respectively. NOx emissions increased with the application of the hydrogen enrichment strategy for the Wankel engine.
Integration of a Multi-Stack Fuel Cell System in Microgrids: A Solution Based on Model Predictive Control
Sep 2020
Publication
This paper proposes a multi-objective model predictive control (MPC) designed for the power management of a multi-stack fuel cell (FC) system integrated into a renewable sources-based microgrid. The main advantage of MPC is the fact that it allows the current timeslot to be optimized while taking future timeslots into account. The multi-objective function solves the problem related to the power dispatch at time that includes criteria to reduce the multi-stack FC degradation operating and maintenance costs as well as hydrogen consumption. Regarding the scientific literature the novelty of this paper lies in the proposal of a generalized MPC controller for a multi-stack FC that can be used independently of the number of stacks that make it up. Although all the stacks that make up the modular FC system are identical their levels of degradation in general will not be. Thus over time each stack can present a different behavior. Therefore the power control strategy cannot be based on an equal distribution according to the nominal power of each stack. On the contrary the control algorithm should take advantage of the characteristics of the multi-stack FC concept distributing operation across all the stacks regarding their capacity to produce power/energy and optimizing the overall performance.
A Recent Review of Primary Hydrogen Carriers, Hydrogen Production Methods, and Applications
Mar 2023
Publication
Hydrogen is a promising energy carrier especially for transportation owing to its unique physical and chemical properties. Moreover the combustion of hydrogen gas generates only pure water; thus its wide utilization can positively affect human society to achieve global net zero CO2 emissions by 2050. This review summarizes the characteristics of the primary hydrogen carriers such as water methane methanol ammonia and formic acid and their corresponding hydrogen production methods. Additionally state-of-the-art studies and hydrogen energy applications in recent years are also included in this review. In addition in the conclusion section we summarize the advantages and disadvantages of hydrogen carriers and hydrogen production techniques and suggest the challenging tasks for future research.
Multi-criteria Optimisation of Fermentative and Solar-driven Electrolytic Hydrogen and Electricity Supply-demand Network with Hybrid Storage System
May 2023
Publication
Harnessing renewable resources such as solar energy and biogenic waste for hydrogen production offers a path toward a carbon-neutral industrial economy. This study suggests the development of a renewable-based hydrogen and power supply facility (HPSF) that relies on fermentation and solar-driven electrolysis technologies to achieve penetration of renewable hydrogen and electricity in the industrial symbiosis. Literature studies reported that the hybrid battery-hydrogen storage system could effectively improve the sustainability and reliability of renewable energy supplies yet its application under diurnal and seasonal renewable resource variations has not been well studied. Hence this work develops a multi-criteria optimisation framework for the configuration design of the proposed HPSF that concurrently targets industrial hydrogen and electrical loads with the consideration of diurnal and seasonal renewable resource variations. Case scenarios with different storage applications are presented to evaluate the role of storage in improving economic and environmental sustainability. The results show that the application of hybrid storage with molten carbonate fuel cell (MCFC) systems is preferred from a comprehensive sustainability standpoint which improves the sustainability-weighted return-on investment metric (SWROIM) score by 4%/yr compared to HPSF without storage application. On the other hand the application of a single-battery system is the most economical solution with a return on investment (ROI) of 0.7%/yr higher than the hybrid storage approach. The research outcome could provide insights into the integration of fermentative and solar-driven electrolytic hydrogen production technologies into the industrial symbiosis to further enhance a sustainable economy.
Optimal Incorporation of Intermittent Renewable Energy Storage Units and Green Hydrogen Production in the Electrical Sector
Mar 2023
Publication
This paper presents a mathematical programming approach for the strategic planning of hydrogen production from renewable energies and its use in electric power generation in conventional technologies. The proposed approach aims to determine the optimal selection of the different types of technologies electrolyzers and storage units (energy and hydrogen). The approach considers the implementation of an optimization methodology to select a representative data set that characterizes the total annual demand. The economic objective aims to determine the minimum cost which is composed of the capital costs in the acquisition of units operating costs of such units costs of production and transmission of energy as well as the cost associated with the emissions generated which is related to an environmental tax. A specific case study is presented in the Mexican peninsula and the results show that it is possible to produce hydrogen at a minimum sale price of 4200 $/tonH2 with a total cost of $5.1687 × 106 and 2.5243 × 105 tonCO2eq. In addition the financial break-even point corresponds to a sale price of 6600 $/tonH2 . The proposed model determines the trade-offs between the cost and the emissions generated.
Hydrogenerally - Episode 10: Green Hydrogen Production
Feb 2023
Publication
Debra Jones Chemistry Knowledge Transfer Manager and Simon Buckley Zero Emission Mobility Knowledge Transfer Manager from Innovate UK KTN talk about green hydrogen production with their special guest Chris Jackson CEO & Founder at Protium.
This podcast discussion centres around methods of producing clean hydrogen from renewable energy sources the innovative projects Protium is working on and how much green hydrogen will the UK produce by 2030 and beyond.
The podcast can be found on their website.
This podcast discussion centres around methods of producing clean hydrogen from renewable energy sources the innovative projects Protium is working on and how much green hydrogen will the UK produce by 2030 and beyond.
The podcast can be found on their website.
CO2 Emissions of Battery Electric Vehicles and Hydrogen Fuel Cell Vehicles
Jun 2023
Publication
During the last few years electric and hydrogen vehicles have become an alternative to cars that use internal combustion engines. The number of electric and hydrogen vehicles sold has increased due to support from local governments and because car manufacturers will stop the production of internal combustion engines in the near future. The emissions of these vehicles while being driven are zero but they still have an impact on the environment due to their fuel. In this article an analysis of carbon dioxide (CO2 ) emissions for two types of vehicles: battery electric vehicles (BEVs) powered by electricity and fuel cell electric vehicles (FCEVs) powered by hydrogen is presented. The analysis considers different values for the mix of power generation and hydrogen production options in comparison to other studies. The CO2 emissions were calculated and compared for the two types of vehicles. The results show that the CO2 emissions of BEVs are lower when compared to FCEVs if the hydrogen is obtained from pollutant sources and is higher if the hydrogen is obtained from nuclear power and renewable energy sources. When compared to conventional combustion engine vehicles BEVs have lower CO2 emissions while the emissions of FCEVs are dependent on the hydrogen production method.
Hydrogenerally - Episode 6: Waste to Hydrogen
Nov 2022
Publication
In this sixth episode Steffan Eldred Hydrogen Innovation Network Knowledge Transfer Manager and Debra Jones Chemistry Knowledge Transfer Manager from Innovate UK KTN discuss why converting waste to hydrogen is so important and explore the hydrogen transition opportunities and challenges in this sector alongside their special guest Rob Dent Senior Research Engineer - Energy Linde and Application Sales Engineer at BOC UK & Ireland.
The podcast can be found on their website.
The podcast can be found on their website.
Integrated Demand Response Design of Integrated Energy System with Mobile Hydrogen Energy Storage in Time-Domain Two-Port Model
Dec 2022
Publication
With the development of energy integration technology demand response (DR) has gradually evolved into integrated demand response (IDR). In this study for the integrated energy system (IES) on the distribution grid side with electricity heat natural gas network and hydrogen energy equipment the analogy relationship between the thermal and mobile hydrogen energy storage networks is proposed. Moreover a unified model that reflects network commonalities across different energy forms is established. Then considering the time delay of the IES in the nontransient network a time-domain two-port model of the IES considering the time delay is established. This model shows the joint effect of time and space on system parameters. Finally this study validates the model in the application of DR. The verification results show that in DR the time-domain two-port model can accurately “cut peaks and fill valleys” for the IES and effectively reduce the operating cost of the IES system.
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