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Identifying Informed Beliefs about Hydrogen Technologies Across the Energy Supply Chain
Apr 2023
Publication
Developing a thriving hydrogen industry will depend on public and community support. Past research mainly focusing on the acceptance of hydrogen fuelling stations and cars suggests that people generally support hydrogen energy technology (HET). Few studies have however considered how people think about other components of the hydrogen supply chain (i.e. technologies required to make store transport and use hydrogen). Moreover there has been limited research investigating how people interpret and develop beliefs about HET after being presented with technical information. This paper attempts to address these research gaps by presenting the findings from four face-to-face focus group discussions conducted in Australia. The findings suggest that people have differing views about HET which depends on the type of technology and these views influence levels of support. The study also revealed concerns about a range of other factors that have yet to be considered in hydrogen acceptance research (e.g. perceived water use efficiency and indirect benefits). The findings highlight the value of qualitative research for identifying salient beliefs that shape attitudes towards HET and provide recommendations for future research and how to effectively communicate with the public and communities about an emerging hydrogen industry.
Prospects and Challenges of Green Hydrogen Economy via Multi-Sector Global Symbiosis in Qatar
Jan 2021
Publication
Low carbon hydrogen can be an excellent source of clean energy which can combat global climate change and poor air quality. Hydrogen based economy can be a great opportunity for a country like Qatar to decarbonize its multiple sectors including transportation shipping global energy markets and industrial sectors. However there are still some barriers to the realization of a hydrogen-based economy which includes large scale hydrogen production cost infrastructure investments bulk storage transport & distribution safety consideration and matching supply-demand uncertainties. This paper highlights how the aforementioned challenges can be handled strategically through a multi-sector industrial-urban symbiosis for the hydrogen supply chain implementation. Such symbiosis can enhance the mutual relationship between diverse industries and urban planning by exploring varied scopes of multi-purpose hydrogen usage (i.e. clean energy source as a safer carrier industrial feedstock and intermittent products vehicle and shipping fuel and international energy trading etc.) both in local and international markets. It enables individual entities and businesses to participate in the physical exchange of materials by-products energy and water with strategic advantages for all participants. Besides waste/by-product exchanges several different kinds of synergies are also possible such as the sharing of resources and shared facilities. The diversified economic base regional proximity and the facilitation of rules strategies and policies may be the key drivers that support the creation of a multi-sector hydrogen supply chain in Qatar.
Hydrogen Informed Gurson Model for Hydrogen Embrittlement Simulation
Jul 2019
Publication
Hydrogen-microvoid interactions were studied via unit cell analyses with different hydrogen concentrations. The absolute failure strain decreases with hydrogen concentration but the failure loci were found to follow the same trend dependent only on stress triaxiality in other words the effects of geometric constraint and hydrogen on failure are decoupled. Guided by the decoupling principle a hydrogen informed Gurson model is proposed. This model is the first practical hydrogen embrittlement simulation tool based on the hydrogen enhanced localized plasticity (HELP) mechanism. It introduces only one additional hydrogen related parameter into the Gurson model and is able to capture hydrogen enhanced internal necking failure of microvoids with accuracy; its parameter calibration procedure is straightforward and cost efficient for engineering purpose
An Improved State Machine-based Energy Management Strategy for Renewable Energy Microgrid with Hydrogen Storage System
Oct 2022
Publication
Renewable energy (solar and wind) sources have evolved dramatically in recent years around the globe primarily because they have the potential to generate environmentally friendly energy. However operating systems with high renewable energy penetration remain challenging due to the stochastic nature of these energy sources. To tackle these problems the authors propose a state machine-based energy management strategy combined with a hysteresis band control strategy for renewable energy hybrid microgrids that integrates hydrogen storage systems. By considering the power difference between the renewable energy source and the demand the battery’s state of charge and the hydrogen storage level the proposed energy management strategy can control the power of fuel cells electrolyzers and batteries in a microgrid and the power imported into/exported from the main grid. The results showed that the energy management strategy provides the following advantages: (1) the power supply and demand balance in the microgrid was balanced (2) the lifespans of the electrolyzer and fuel cell were extended and (3) the state of charge of the battery and the stored level of the hydrogen were appropriately ensured.
Tourist Preferences for Fuel Cell Vehicle Rental: Going Green with Hydrogen on the Island of Tenerife
Mar 2023
Publication
Using a discrete choice experiment (DCE) a survey of international tourists on the island of Tenerife is conducted to examine preferences for fuel cell vehicle (FCV) rental while on vacation. Survey respondents were generally supportive of FCVs and willing to hire one as part of their trip but for most individuals this is contingent on an adequate fuel station infrastructure. A latent class model was used to identify three distinct groups; one of which potentially represent early adopters e they have a high willingness-to-pay (WTP) for green hydrogen and are more likely to accept a low number of fuel stations but it could be challenging to convince them to use FCVs if they are not run on green hydrogen.
Green Hydrogen Production through Ammonia Decomposition Using Non-Thermal Plasma
Sep 2023
Publication
Liquid hydrogen carriers will soon play a significant role in transporting energy. The key factors that are considered when assessing the applicability of ammonia cracking in large-scale projects are as follows: high energy density easy storage and distribution the simplicity of the overall process and a low or zero-carbon footprint. Thermal systems used for recovering H2 from ammonia require a reaction unit and catalyst that operates at a high temperature (550–800 ◦C) for the complete conversion of ammonia which has a negative effect on the economics of the process. A non-thermal plasma (NTP) solution is the answer to this problem. Ammonia becomes a reliable hydrogen carrier and in combination with NTP offers the high conversion of the dehydrogenation process at a relatively low temperature so that zero-carbon pure hydrogen can be transported over long distances. This paper provides a critical overview of ammonia decomposition systems that focus on non-thermal methods especially under plasma conditions. The review shows that the process has various positive aspects and is an innovative process that has only been reported to a limited extent.
Recent Progress in Conducting Polymers for Hydrogen Storage and Fuel Cell Applications
Oct 2020
Publication
Hydrogen is a clean fuel and an abundant renewable energy resource. In recent years huge scientific attention has been invested to invent suitable materials for its safe storage. Conducting polymers has been extensively investigated as a potential hydrogen storage and fuel cell membrane due to the low cost ease of synthesis and processability to achieve the desired morphological and microstructural architecture ease of doping and composite formation chemical stability and functional properties. The review presents the recent progress in the direction of material selection modification to achieve appropriate morphology and adsorbent properties chemical and thermal stabilities. Polyaniline is the most explored material for hydrogen storage. Polypyrrole and polythiophene has also been explored to some extent. Activated carbons derived from conducting polymers have shown the highest specific surface area and significant storage. This review also covers recent advances in the field of proton conducting solid polymer electrolyte membranes in fuel cells application. This review focuses on the basic structure synthesis and working mechanisms of the polymer materials and critically discusses their relative merits.
CFD Modelling of Hydrogen and Hydrogen-methane Explosions - Analysis of Varying Concentration and Reduced Oxygen Atmospheres
Feb 2023
Publication
This paper evaluates the predictive capabilities of the advanced consequence model FLACS-CFD for deflagrations involving hydrogen. Two modelling approaches are presented: the extensively validated model system originally developed for hydrocarbons included in FLACS-CFD 22.1 and a Markstein number dependent model implemented in the in-house version FLACS-CFD 22.1 IH. The ability of the models to predict the overpressure and the flame arrival time for scenarios with different concentrations of hydrogen and thus different Lewis and Markstein numbers is assessed. Furthermore the effect of adding methane or nitrogen on overpressure for different regimes of premixed combustion are investigated. The validation dataset includes deflagrations in the open or in congested open areas and vented deflagrations in empty or congested enclosures. The overpressure predictions by FLACS-CFD 22.1 IH are found to be more accurate than those obtained with FLACS-CFD 22.1 for scenarios with varying hydrogen concentrations and/or added nitrogen or methane in the mixture. The predictions by FLACS-CFD 22.1 IH for lean hydrogen mixtures are within a factor of 2 of the values observed in the experiments. Further development of the model is needed for more accurate prediction of deflagrations involving rich hydrogen mixtures as well as scenarios with other fuels and/or conditions where the initial pressure or temperature deviate significantly from ambient conditions.
Fuelling the Transition Podcast: Using Hydrogen to Achieve Net-zero
Jan 2021
Publication
In order to achieve the EU’s target of 55% carbon reduction by 2030 hydrogen will have to make a key contribution to the energy mix. With many applications in industrial heat mobility power and chemical refineries hydrogen can be used to decarbonise where electrification is not possible. Equinor is a broad energy company with 21000 employees developing oil gas wind and solar energy in more than 30 countries worldwide. Equinor have been at the forefront of promoting hydrogen projects in Europe and developing low-carbon hydrogen solutions. In this episode Johan Leuraers Chief Consultant - Policy and Regulatory Affairs at Equinor and John Williams Head of Hydrogen Expertise Cluster at AFRY Management Consulting join us to discuss the main barriers to the uptake of hydrogen and the next steps to kick-start the hydrogen economy.
The podcast can be found on their website.
The podcast can be found on their website.
Optimal Scheduling of Multi-microgrids with Power to Hydrogen Considering Federated Demand Response
Sep 2022
Publication
Hydrogen is regarded as a promising fuel in the transition to clean energy. Nevertheless as the demand for hydrogen increases some microgrids equipped with P2H (MGH) will encounter the issue of primary energy deficiency. Meanwhile some microgrids (MGs) face the difficulty of being unable to consume surplus energy locally. Hence we interconnect MGs with different energy characteristics and then establish a collaborative scheduling model of multi-microgrids (MMGs). In this model a federated demand response (FDR) program considering predictive mean voting is designed to coordinate controllable loads of electricity heat and hydrogen in different MGs. With the coordination of FDR the users’ satisfaction and comfort in each MG are kept within an acceptable range. To further adapt to an actual working condition of the microturbine (MT) in MGH a power interaction method is proposed to maintain the operating power of the MT at the optimum load level and shave peak and shorten the operating periods of MT. In the solution process the sequence operation theory is utilized to deal with the probability density of renewable energy. A series of case studies on a test system of MMG demonstrate the effectiveness of the proposed method.
Exploring Technological Solutions for Onboard Hydrogen Storage Systems Through a Heterogeneous Knowledge Network: From Current State to Future Research Opportunities
Jun 2022
Publication
With the imminent threat of the energy crises innovation in energy technologies is happening world-wide. The aim is to reduce our reliance on fossil fuels. Electric vehicles with fuel-cells that use hydrogen as an energy carrier are touted to be one of the most important potential replacements of the gasoline vehicle in both future transportation scenarios and emerging smart energy grids. However hydrogen storage is a major technical barrier that lies between where we are now and the mass application of hydrogen energy. Further exploration of onboard hydrogen storage systems (OHSS) is urgently needed and in this regard a comprehensive technology opportunity analysis will help. Hence with this research we drew on scientific papers and patents related to OHSS and developed a novel methodology for investigating the past present and future development trends in OHSS. Specifically we constructed a heterogeneous knowledge network using a unique multi-component structure with three core components: hydrogen carriers hydrogen storage materials and fuel cells. From this network we extracted both the developed and underdeveloped technological solutions in the field and applied a well-designed evaluation system and prediction model to score the future development potential of these technological solutions. What emerged was the most promising directions of research in the short medium and long term. The results show that our methodology can effectively identify technology opportunities in OHSS along with providing valuable decision support to researchers and enterprise managers associated with the development and application of OHSS.
Toward Sustainability: An Overview of the Use of Green Hydrogen in the Agriculture and Livestock Sector
Aug 2023
Publication
The agro-livestock sector produces about one third of global greenhouse gas (GHG) emissions. Since more energy is needed to meet the growing demand for food and the industrial revolution in agriculture renewable energy sources could improve access to energy resources and energy security reduce dependence on fossil fuels and reduce GHG emissions. Hydrogen production is a promising energy technology but its deployment in the global energy system is lagging. Here we analyzed the theoretical and practical application of green hydrogen generated by electrolysis of water powered by renewable energy sources in the agro-livestock sector. Green hydrogen is at an early stage of development in most applications and barriers to its large-scale deployment remain. Appropriate policies and financial incentives could make it a profitable technology for the future.
Expert Perceptions of Game-changing Innovations towards Net Zero
Dec 2022
Publication
Current technological improvements are yet to put the world on track to net-zero which will require the uptake of transformative low-carbon innovations to supplement mitigation efforts. However the role of such innovations is not yet fully understood; some of these ‘miracles’ are considered indispensable to Paris Agreement-compliant mitigation but their limitations availability and potential remain a source of debate. We evaluate such potentially game-changing innovations from the experts’ perspective aiming to support the design of realistic decarbonisation scenarios and better-informed net-zero policy strategies. In a worldwide survey 260 climate and energy experts assessed transformative innovations against their mitigation potential at-scale availability and/or widescale adoption and risk of delayed diffusion. Hierarchical clustering and multi-criteria decision-making revealed differences in perceptions of core technological innovations with next generation energy storage alternative building materials iron-ore electrolysis and hydrogen in steelmaking emerging as top priorities. Instead technologies highly represented in well-below-2◦C scenarios seemingly feature considerable and impactful delays hinting at the need to re-evaluate their role in future pathways. Experts’ assessments appear to converge more on the potential role of other disruptive innovations including lifestyle shifts and alternative economic models indicating the importance of scenarios including non-technological and demand-side innovations. To provide insights for expert elicitation processes we finally note caveats related to the level of representativeness among the 260 engaged experts the level of their expertise that may have varied across the examined innovations and the potential for subjective interpretation to which the employed linguistic scales may be prone to.
Thermocatalytic Hydrogen Production Through Decomposition of Methane-A Review
Oct 2021
Publication
Consumption of fossil fuels especially in transport and energy-dependent sectors has led to large greenhouse gas production. Hydrogen is an exciting energy source that can serve our energy purposes and decrease toxic waste production. Decomposition of methane yields hydrogen devoid of COx components thereby aiding as an eco-friendly approach towards large-scale hydrogen production. This review article is focused on hydrogen production through thermocatalytic methane decomposition (TMD) for hydrogen production. The thermodynamics of this approach has been highlighted. Various methods of hydrogen production from fossil fuels and renewable resources were discussed. Methods including steam methane reforming partial oxidation of methane auto thermal reforming direct biomass gasification thermal water splitting methane pyrolysis aqueous reforming and coal gasification have been reported in this article. A detailed overview of the different types of catalysts available the reasons behind their deactivation and their possible regeneration methods were discussed. Finally we presented the challenges and future perspectives for hydrogen production via TMD. This review concluded that among all catalysts nickel ruthenium and platinum-based catalysts show the highest activity and catalytic efficiency and gave carbon-free hydrogen products during the TMD process. However their rapid deactivation at high temperatures still needs the attention of the scientific community.
Net Hydrogen Consumption Minimization of Fuel Cell Hybrid Trains Using a Time-Based Co-Optimization Model
Apr 2022
Publication
With increasing concerns on transportation decarbonization fuel cell hybrid trains (FCHTs) attract many attentions due to their zero carbon emissions during operation. Since fuel cells alone cannot recover the regenerative braking energy (RBE) energy storage devices (ESDs) are commonly deployed for the recovery of RBE and provide extra traction power to improve the energy efficiency. This paper aims to minimize the net hydrogen consumption (NHC) by co-optimizing both train speed trajectory and onboard energy management using a time-based mixed integer linear programming (MILP) model. In the case with the constraints of speed limits and gradients the NHC of co-optimization reduces by 6.4% compared to the result obtained by the sequential optimization which optimizes train control strategies first and then the energy management. Additionally the relationship between NHC and employed ESD capacity is studied and it is found that with the increase of ESD capacity the NHC can be reduced by up to 30% in a typical route in urban railway transit. The study shows that ESDs play an important role for FCHTs in reducing NHC and the proposed time-based co-optimization model can maximize the energy-saving benefits for such emerging traction systems with hybrid energy sources including both fuel cells and ESD.
Solar Hydrogen for High Capacity, Dispatchable, Long-distance Energy transmission – A Case Study for Injection in the Greenstream Natural Gas Pipeline
Nov 2022
Publication
This paper presents the results of techno-economic modelling for hydrogen production from a photovoltaic battery electrolyser system (PBES) for injection into a natural gas transmission line. Mellitah in Libya connected to Gela in Italy by the Greenstream subsea gas transmission line is selected as the location for a case study. The PBES includes photovoltaic (PV) arrays battery electrolyser hydrogen compressor and large-scale hydrogen storage to maintain constant hydrogen volume fraction in the pipeline. Two PBES configurations with different large-scale storage methods are evaluated: PBESC with compressed hydrogen stored in buried pipes and PBESL with liquefied hydrogen stored in spherical tanks. Simulated hourly PV electricity generation is used to calculate the specific hourly capacity factor of a hypothetical PV array in Mellitah. This capacity factor is then used with different PV sizes for sizing the PBES. The levelised cost of delivered hydrogen (LCOHD) is used as the key techno-economic parameter to optimise the size of the PBES by equipment sizing. The costs of all equipment except the PV array and batteries are made to be a function of electrolyser size. The equipment sizes are deemed optimal if PBES meets hydrogen demand at the minimum LCOHD. The techno-economic performance of the PBES is evaluated for four scenarios of fixed and constant hydrogen volume fraction targets in the pipeline: 5% 10% 15% and 20%. The PBES can produce up to 106 kilotonnes of hydrogen per year to meet the 20% target at an LCOHD of 3.69 €/kg for compressed hydrogen storage (PBESC) and 2.81 €/kg for liquid hydrogen storage (PBESL). Storing liquid hydrogen at large-scale is significantly cheaper than gaseous hydrogen even with the inclusion of a significantly larger PV array that is required to supply additional electrcitiy for liquefaction.
Hydrogen Production by Solar Thermochemical Water-Splitting Cycle via a Beam Down Concentrator
May 2021
Publication
About 95% of the hydrogen presently produced is from natural gas and coal and the remaining 5% is generated as a by-product from the production of chlorine through electrolysis1 . In the hydrogen economy (Crabtree et al. 2004; Penner 2006; Marbán and Valdés-Solís 2007) hydrogen is produced entirely from renewable energy. The easiest approach to advance renewable energy production is through solar photovoltaic and electrolysis a pathway of high technology readiness level (TRL) suffering however from two downfalls. First of all electricity is already an energy carrier and transformation with a penalty into another energy carrier hydrogen is in principle flawed. The second problem is that the efficiency of commercial solar panels is relatively low. The cadmium telluride (CdTe) thin-film solar cells have a solar energy conversion efficiency of 17%. Production of hydrogen using the current best processes for water electrolysis has an efficiency of ∼70%. As here explained the concentrated solar energy may be used to produce hydrogen using thermochemical water-splitting cycles at much global higher efficiency (fuel energy to incident sun energy). This research and development (R&D) effort is therefore undertaken to increase the TRL of this approach as a viable and economical option.
The Potential Role of a Hydrogen Network in Europe
Jul 2023
Publication
Europe’s electricity transmission expansion suffers many delays despite its significance for integrating renewable electricity. A hydrogen network reusing the existing gas network could not only help to supply the demand for low-emission fuels but could also balance variations in wind and solar energies across the continent and thus avoid power grid expansion. Our investigation varies the allowed expansion of electricity and hydrogen grids in net-zero CO2 scenarios for a sector-coupled European energy system capturing transmission bottlenecks renewable supply and demand variability and pipeline retrofitting and geological storage potentials. We find that a hydrogen network connecting regions with low-cost and abundant renewable potentials to demand centers electrofuel production and cavern storage sites reduces system costs by up to 26 bnV/a (3.4%). Although expanding both networks together can achieve the largest cost reductions by 9.9% the expansion of neither is essential for a net-zero system as long as higher costs can be accepted and flexibility options allow managing transmission bottlenecks.
A Green Route for Hydrogen Producton from Alkaline Thermal Treatment (ATT) of Biomass with Carbon Storage
Apr 2023
Publication
Hydrogen a green energy carrier is one of the most promising energy sources. However,it is currently mainly produced from depleting fossil fuels with high carbon emissions which has serious negative effects on the economy and environment. To address this issue sustainable hydrogen production from bio-energy with carbon capture and storage (HyBECCS) is an ideal technology to reduce global carbon emissions while meeting energy demand. This review presents an overview of the latest progress in alkaline thermal treatment (ATT) of biomass for hydrogen production with carbon storage especially focusing on the technical characteristics and related challenges from an industrial application perspective. Additionally the roles of alkali and catalyst in the ATT process are critically discussed and several aspects that have great influences on the ATT process such as biomass types reaction parameters and reactors are expounded. Finally the potential solutions to the general challenges and obstacles to the future industrial-scale application of ATT of biomass for hydrogen production are proposed.
CFD Thermo‑Hydraulic Evaluation of a Liquid Hydrogen Storage Tank with Different Insulation Thickness in a Small‑Scale Hydrogen Liquefier
Aug 2023
Publication
Accurate evaluation of thermo‑fluid dynamic characteristics in tanks is critically important for designing liquid hydrogen tanks for small‑scale hydrogen liquefiers to minimize heat leakage into the liquid and ullage. Due to the high costs most future liquid hydrogen storage tank designs will have to rely on predictive computational models for minimizing pressurization and heat leakage. Therefore in this study to improve the storage efficiency of a small‑scale hydrogen liquefier a three‑ dimensional CFD model that can predict the boil‑off rate and the thermo‑fluid characteristics due to heat penetration has been developed. The prediction performance and accuracy of the CFD model was validated based on comparisons between its results and previous experimental data and a good agreement was obtained. To evaluate the insulation performance of polyurethane foam with three different insulation thicknesses the pressure changes and thermo‑fluid characteristics in a partially liquid hydrogen tank subject to fixed ambient temperature and wind velocity were investigated nu‑ merically. It was confirmed that the numerical simulation results well describe not only the temporal variations in the thermal gradient due to coupling between the buoyance and convection but also the buoyancy‑driven turbulent flow characteristics inside liquid hydrogen storage tanks with differ‑ ent insulation thicknesses. In the future the numerical model developed in this study will be used for optimizing the insulation systems of storage tanks for small‑scale hydrogen liquefiers which is a cost‑effective and highly efficient approach.
Can the Hydrogen Economy Concept be the Solution to the Future Energy Crisis?
Feb 2022
Publication
The Hydrogen Economy concept is being proposed as a means of reducing and eventually decarbonising the world’s energy use. It looks to hydrogen as being a replacement for methane (natural gas) and generally as a way of removing all fossil fuels from the energy supply. The concept however has at least four flaws as follows: (1) hydrogen has significantly different properties to methane; (2) hydrogen has properties that create significant hazards; (3) hydrogen has a very small initiation (activation) energy; and (4) liquid hydrogen cannot readily replace liquefied natural gas (LNG). Hydrogen’s hazards will prevent it from being accepted in a societal sense. To the question ‘Can the Hydrogen Economy concept be the solution to the future energy crisis?’ the answer is ‘no’. Hydrogen has and will have a role in world energy but that role will be limited to industry. For the future we need an advanced electric economy.
An Insight into Underground Hydrogen Storage in Italy
Apr 2023
Publication
Hydrogen is a key energy carrier that could play a crucial role in the transition to a low-carbon economy. Hydrogen-related technologies are considered flexible solutions to support the large-scale implementation of intermittent energy supply from renewable sources by using renewable energy to generate green hydrogen during periods of low demand. Therefore a short-term increase in demand for hydrogen as an energy carrier and an increase in hydrogen production are expected to drive demand for large-scale storage facilities to ensure continuous availability. Owing to the large potential available storage space underground hydrogen storage offers a viable solution for the long-term storage of large amounts of energy. This study presents the results of a survey of potential underground hydrogen storage sites in Italy carried out within the H2020 EU Hystories “Hydrogen Storage In European Subsurface” project. The objective of this work was to clarify the feasibility of the implementation of large-scale storage of green hydrogen in depleted hydrocarbon fields and saline aquifers. By analysing publicly available data mainly well stratigraphy and logs we were able to identify onshore and offshore storage sites in Italy. The hydrogen storage capacity in depleted gas fields currently used for natural gas storage was estimated to be around 69.2 TWh.
Hydrogen Production by Water Electrolysis Technologies: A Review
Sep 2023
Publication
Hydrogen as an energy source has been identified as an optimal pathway for mitigating climate change by combining renewable electricity with water electrolysis systems. Proton exchange membrane (PEM) technology has received a substantial amount of attention because of its ability to efficiently produce high-purity hydrogen while minimising challenges associated with handling and maintenance. Another hydrogen generation technology alkaline water electrolysis (AWE) has been widely used in commercial hydrogen production applications. Anion exchange membrane (AEM) technology can produce hydrogen at relatively low costs because the noble metal catalysts used in PEM and AWE systems are replaced with conventional low-cost electrocatalysts. Solid oxide electrolyzer cell (SOEC) technology is another electrolysis technology for producing hydrogen at relatively high conversion efficiencies low cost and with low associated emissions. However the operating temperatures of SOECs are high which necessitates long startup times. This review addresses the current state of technologies capable of using impure water in water electrolysis systems. Commercially available water electrolysis systems were extensively discussed and compared. The technical barriers of hydrogen production by PEM and AEM were also investigated. Furthermore commercial PEM stack electrolyzer performance was evaluated using artificial river water (soft water). An integrated system approach was recommended for meeting the power and pure water demands using reversible seawater by combining renewable electricity water electrolysis and fuel cells. AEM performance was considered to be low requiring further developments to enhance the membrane’s lifetime.
Transition Analysis of Budgetary Allocation for Projects on Hydrogen-Related Technologies in Japan
Oct 2020
Publication
Hydrogen technologies are promising candidates of new energy technologies for electric power load smoothing. However regardless of long-term public investment hydrogen economy has not been realized. In Japan the National Research and Development Institute of New Energy and Industrial Technology Development Organization (NEDO) a public research-funding agency has invested more than 200 billion yen in the technical development of hydrogen-related technologies. However hydrogen technologies such as fuel cell vehicles (FCVs) have not been disseminated yet. Continuous and strategic research and development (R&D) are needed but there is a lack of expertise in this field. In this study the transition of the budgetary allocations by NEDO were analyzed by classifying NEDO projects along the hydrogen supply chain and research stage. We found a different R&D focus in different periods. From 2004 to 2007 empirical research on fuel cells increased with the majority of research focusing on standardization. From 2008 to 2011 investment in basic research of fuel cells increased again the research for verification of fuel cells continued and no allocation for research on hydrogen production was confirmed. Thereafter the investment trend did not change until around 2013 when practical application of household fuel cells (ENE-FARM) started selling in 2009 in terms of hydrogen supply chain. Hydrogen economy requires a different hydrogen supply infrastructure that is an existing infrastructure of city gas for ENE-FARM and a dedicated infrastructure for FCVs (e.g. hydrogen stations). We discussed the possibility that structural inertia could prevent the transition to investing more in hydrogen infrastructure from hydrogen utilization technology. This work has significant implications for designing national research projects to realize hydrogen economy.
Interdisciplinary Perspectives on Offshore Energy System Integration in the North Sea: A Systematic Literature Review
Oct 2023
Publication
To facilitate the rapid and large-scale developments of offshore wind energy scholars policymakers and infrastructure developers must start considering its integration into the larger onshore energy system. Such offshore system integration is defined as the coordinated approach to planning and operation of energy generation transport and storage in the offshore energy system across multiple energy carriers and sectors. This article conducts a systematic literature review to identify infrastructure components of offshore energy system integration (including alternative cable connections offshore energy storage and power-to-hydrogen applications) and barriers to their development. An interdisciplinary perspective is provided where current offshore developments require not only mature and economically feasible technologies but equally strong legal and governance frameworks. The findings demonstrate that current literature lacks a holistic perspective on the offshore energy system. To date techno-economic assessments solving challenges of specific infrastructure components prevail over an integrated approach. Nevertheless permitting issues gaps in legal frameworks strict safety and environmental regulations and spatial competition also emerge as important barriers. Overall this literature review emphasizes the necessity of aligning various disciplines to provide a fundamental approach for the development of an integrated offshore energy system. More specifically timely policy and legal developments are key to incentivize technical development and enable economic feasibility of novel components of offshore system integration. Accordingly to maximize real-world application and policy learning future research will benefit from an interdisciplinary perspective.
Comparative Exergy and Environmental Assessment of the Residual Biomass Gasification Routes for Hydrogen and Ammonia Production
Jul 2023
Publication
The need to reduce the dependency of chemicals on fossil fuels has recently motivated the adoption of renewable energies in those sectors. In addition due to a growing population the treatment and disposition of residual biomass from agricultural processes such as sugar cane and orange bagasse or even from human waste such as sewage sludge will be a challenge for the next generation. These residual biomasses can be an attractive alternative for the production of environmentally friendly fuels and make the economy more circular and efficient. However these raw materials have been hitherto widely used as fuel for boilers or disposed of in sanitary landfills losing their capacity to generate other by-products in addition to contributing to the emissions of gases that promote global warming. For this reason this work analyzes and optimizes the biomass-based routes of biochemical production (namely hydrogen and ammonia) using the gasification of residual biomasses. Moreover the capture of biogenic CO2 aims to reduce the environmental burden leading to negative emissions in the overall energy system. In this context the chemical plants were designed modeled and simulated using Aspen plus™ software. The energy integration and optimization were performed using the OSMOSE Lua Platform. The exergy destruction exergy efficiency and general balance of the CO2 emissions were evaluated. As a result the irreversibility generated by the gasification unit has a relevant influence on the exergy efficiency of the entire plant. On the other hand an overall negative emission balance of −5.95 kgCO2/kgH2 in the hydrogen production route and −1.615 kgCO2/kgNH3 in the ammonia production route can be achieved thus removing from the atmosphere 0.901 tCO2/tbiomass and 1.096 tCO2/tbiomass respectively.
Selected Materials and Technologies for Electrical Energy Sector
Jun 2023
Publication
Ensuring the energy transition in order to decrease CO2 and volatile organic compounds emissions and improve the efficiency of energy processes requires the development of advanced materials and technologies for the electrical energy sector. The article reviews superconducting materials functional nanomaterials used in the power industry mainly due to their magnetic electrical optical and dielectric properties and the thin layers of amorphous carbon nitride which properties make them an important material from the point of view of environmental protection optoelectronic photovoltaic and energy storage. The superconductivity-based technologies material processing and thermal and nonthermal plasma generation have been reviewed as technologies that can be a solution to chosen problems in the electrical energy sector and environment. The study explains directly both—the basics and application potential of low and high-temperature superconductors as well as peculiarities of the related manufacturing technologies for Roebel cables 1G and 2G HTS tapes and superconductor coil systems. Among the superconducting materials particular attention was paid to the magnesium di-boride MgB2 and its potential applications in the power industry. The benefits of the use of carbon films with amorphous structures in electronics sensing technologies solar cells FETs and memory devices were discussed. The article provides the information about most interesting from the R&D point of view groups of materials for PV applications. It summarises the advantages and disadvantages of their use regarding commercial requirements such as efficiency lifetime light absorption impact on the environment costs of production and weather dependency. Silicon processing inkjet printing vacuum deposition and evaporation technologies that allow obtaining improved and strengthened materials for solar cell manufacturing are also described. In the case of the widely developed plasma generation field waste-to-hydrogen technology including both thermal and non-thermal plasma techniques has been discussed. The review aims to draw attention to the problems faced by the modern power industry and to encourage research in this area because many of these problems can only be solved within the framework of interdisciplinary and international cooperation.
Chemical Kinetic Analysis of High-Pressure Hydrogen Ignition and Combustion toward Green Aviation
Jan 2024
Publication
In the framework of the “Multidisciplinary Optimization and Regulations for Low-boom and Environmentally Sustainable Supersonic aviation” project pursued by a consortium of European government and academic institutions coordinated by Politecnico di Torino under the European Commission Horizon 2020 financial support the Italian Aerospace Research Centre is computationally investigating the high-pressure hydrogen/air kinetic combustion in the operative conditions typically encountered in supersonic aeronautic ramjet engines. This task is being carried out starting from the zero-dimensional and one-dimensional chemical kinetic assessment of the complex and strongly pressure-sensitive ignition behavior and flame propagation characteristics of hydrogen combustion through the validation against experimental shock tube and laminar flame speed measurements. The 0D results indicate that the kinetic mechanism by Politecnico di Milano and the scheme formulated by Kéromnès et al. provide the best matching with the experimental ignition delay time measurements carried out in high-pressure shock tube strongly argon-diluted reaction conditions. Otherwise the best behavior in terms of laminar flame propagation is achieved by the Mueller scheme while the other investigated kinetic mechanisms fail to predict the flame speeds at elevated pressures. This confirms the non-linear and intensive pressure-sensitive behavior of hydrogen combustion especially in the critical high-pressure and low-temperature region which is hard to be described by a single all-encompassing chemical model.
Blue Hydrogen Production from Natural Gas Reservoirs: A Review of Application and Feasibility
Feb 2023
Publication
Recently interest in developing H2 strategies with carbon capture and storage (CCS) technologies has surged. Considering that this paper reviews recent literature on blue H2 a potential low-carbon short-term solution during the H2 transition period. Three key aspects were the focus of this paper. First it presents the processes used for blue H2 production. Second it presents a detailed comparison between blue H2 and natural gas as fuels and energy carriers. The third aspect focuses on CO2 sequestration in depleted natural gas reservoirs an essential step for implementing blue H2. Globally ~ 75% of H2 is produced using steam methane reforming which requires CCS to obtain blue H2. Currently blue H2 needs to compete with other advancing technologies such as green H2 solar power battery storage etc. Compared to natural gas and liquefied natural gas blue H2 gas results in lower CO2 emissions since CCS is applied. However transporting liquefied and compressed blue H2 entails higher energy economic and environmental costs. CCS must be appropriately implemented to produce blue H2 successfully. Due to their established capacity to trap hydrocarbons over geologic time scales depleted natural gas reservoirs are regarded as a viable option for CCS. Such a conclusion is supported by several simulation studies and field projects in many countries. Additionally there is much field experience and knowledge on the injection and production performance of natural gas reservoirs. Therefore using the existing site infrastructure converting these formations into storage reservoirs is undemanding.
Routes for Hydrogen Introduction in the Industrial Hard-to-Abate Sectors for Promoting Energy Transition
Aug 2023
Publication
This paper offers a set of comprehensive guidelines aimed at facilitating the widespread adoption of hydrogen in the industrial hard-to-abate sectors. The authors begin by conducting a detailed analysis of these sectors providing an overview of their unique characteristics and challenges. This paper delves into specific elements related to hydrogen technologies shedding light on their potential applications and discussing feasible implementation strategies. By exploring the strengths and limitations of each technology this paper offers valuable insights into its suitability for specific applications. Finally through a specific analysis focused on the steel sector the authors provide in-depth information on the potential benefits and challenges associated with hydrogen adoption in this context. By emphasizing the steel sector as a focal point the authors contribute to a more nuanced understanding of hydrogen’s role in decarbonizing industrial processes and inspire further exploration of its applications in other challenging sectors.
Decarbonisation Options for the Cement Industry
Jan 2023
Publication
The cement industry is a building block of modern society and currently responsible for around 7% of global and 4% of EU CO2 emissions. While facing global competition and a challenging business environment the EU cement sector needs to decarbonise its production processes to comply with the EU’s ambitious 2030 and 2050 climate targets. This report provides a snapshot of the current cement production landscape and discusses future technologies that are being explored by the sector to decarbonise its processes describing the transformational change the industry faces. This report compiles the current projects and announcements to deploy breakthrough technologies which do require high capital investments. However with 2050 just one investment cycle away the sector needs to commercialise new low-CO2 technologies this decade to avoid the risk of stranded assets. As Portland cement production is highly CO2-intensive and EU plants are already operating close to optimum efficiency the industry appears to be focussing on carbon capture storage and utilisation technologies - while breakthroughs in alternative chemistries are still being explored - to reduce emissions. While the EU has played an important role in supporting early stage R&D for these technologies it is now striving to fill the funding gap for the commercialisation of breakthrough technologies. The recent momentum towards CO2-free cement provides the EU with the opportunity to be a frontrunner in creating markets for green cement.
A Review on Experimental Studies Investigating the Effect of Hydrogen Supplementation in CI Diesel Engines—The Case of HYMAR
Aug 2022
Publication
Hydrogen supplementation in diesel Compression Ignition (CI) engines is gaining more attention since it is considered as a feasible solution to tackle the challenges that are related to the emission regulations that will be applied in the forthcoming years. Such a solution is very attractive because it requires only limited modifications to the existing technology of internal combustion CI engines. To this end numerous work on the investigation of an engine’s performance and the effects of emissions when hydrogen is supplied in the engine’s cylinders has been completed by researchers. However contradictory results were found among these studies regarding the efficiency of the engine and the emission characteristics achieved compared to the diesel-only operation. The different conclusions might be attributed to the different characteristics and technology level of the engines that were utilized as well as on the chosen operational parameters. This paper aims to present an overview of the experimental studies that have examined the effects of hydrogen addition in CI four-stroke diesel engines reporting the characteristics of the utilized engines the quantities of hydrogen tested the method of hydrogen induction used as well as the operational conditions tested in order to help interested researchers to easily identify relevant and appropriate studies to perform comparisons or validations by repeating certain cases. The presented data do not include any results or conclusions from these studies. Furthermore an experimental configuration along with the appropriate modifications on a heavy-duty auxiliary generator-set engine that was recently developed by the authors for the purposes of the HYMAR project is presented.
Power Scheduling Optimization Method of Wind-Hydrogen Integrated Energy System Based on the Improved AUKF Algorithm test2
Nov 2022
Publication
With the proposal of China’s green energy strategy the research and development technologies of green energy such as wind energy and hydrogen energy are becoming more and more mature. However the phenomenon of wind abandonment and anti-peak shaving characteristics of wind turbines have a great impact on the utilization of wind energy. Therefore this study firstly builds a distributed wind-hydrogen hybrid energy system model then proposes the power dispatching optimization technology of a wind-hydrogen integrated energy system. On this basis a power allocation method based on the AUKF (adaptive unscented Kalman filter) algorithm is proposed. The experiment shows that the power allocation strategy based on the AUKF algorithm can effectively reduce the incidence of battery overcharge and overdischarge. Moreover it can effectively deal with rapid changes in wind speed. The wind hydrogen integrated energy system proposed in this study is one of the important topics of renewable clean energy technology innovation. Its grid-connected power is stable with good controllability and the DC bus is more secure and stable. Compared with previous studies the system developed in this study has effectively reduced the ratio of abandoned air and its performance is significantly better than the system with separate grid connected fans and single hydrogen energy storage. It is hoped that this research can provide some solutions for the research work on power dispatching optimization of energy systems.
Determining the Production and Transport Cost for H2 on a Global Scale
May 2022
Publication
Hydrogen (H2) produced using renewable energy could be used to reduce greenhouse gas (GHG) emissions in industrial sectors such as steel chemicals transportation and energy storage. Knowing the delivered cost of renewable H2 is essential to decisionmakers looking to utilize it. The cheapest location to source it from as well as the transport method and medium are also crucial information. This study presents a Monte Carlo simulation to determine the delivered cost for renewable H2 for any usage location globally as well as the most cost-effective production location and transport route from nearly 6000 global locations. Several industrially dense locations are selected for case studies the primary two being Cologne Germany and Houston United States. The minimum delivered H2 cost to Cologne is 9.4 €/kg for small scale (no pipelines considered) shipped from northern Egypt as a liquid organic hydrogen carrier (LOHC) and 7.6 €/kg piped directly as H2 gas from southern France for large scale (pipelines considered). For smallscale H2 in Houston the minimum delivered cost is 8.6 €/kg trucked as H2 gas from the western Gulf of Mexico and 7.6 €/kg for large-scale demand piped as H2 gas from southern California. The south-west United States and Mexico northern Chile the Middle East and north Africa south-west Africa and north-west Australia are identified as the regions with the lowest renewable H2 cost potential with production costs ranging from 6.7—7.8 €/kg in these regions. Each is able to supply differing industrially dominant areas. Furthermore the effect of parameters such as year of construction electrolyser and H2 demand is analysed. For the case studies in Houston and Cologne the delivered H2 cost is expected to reduce to about 7.8 €/kg by 2050 in Cologne (no pipelines considered PEM electrolyser) and 6.8 €/kg in Houston.
Life Cycle Analysis of Hydrogen Powered Marine Vessels—Case Ship Comparison Study with Conventional Power System
Aug 2023
Publication
The latest International Maritime Organization strategies aim to reduce 70% of the CO2 emissions and 50% of the Greenhouse Gas (GHG) emissions from maritime activities by 2050 compared to 2008 levels. The EU has set up goals to reduce GHG emissions by at least 55% by 2030 compared to 1990 and achieve net-zero GHG emissions by 2050. The UK aims to achieve more than 68% GHG emission reduction by 2030 and net-zero GHG emissions by 2050. There are many solutions under development to tackle the challenge of meeting the latest decarbonization strategies from the IMO EU and UK among which are hydrogen powered marine vessels. This paper presents a life cycle analysis study for hydrogen fuelled vessels by evaluating their performance in terms of environmental friendliness and economic feasibility. The LCA study will consider the gas emissions and costs during the life stages of the ships including the construction operation maintenance and recycling phases of the selected vessels. The results of the comparisons with the conventional version of the ships (driven by diesel generators) demonstrate the benefits of using hydrogen for marine transportation: over 80% emission reduction and around 60% life cycle cost savings. A sensitivity analysis shows that the prices of fuels and carbon credits can affect the life cycle cost and recommendations for low H2 price and high carbon credit in the future are provided to attract the industry to adopt the new fuel.
Hydrogen Fuel Cell Integration and Testing in a Hybrid-electric Propulsion Rig
Jun 2023
Publication
On the road towards greener aviation hybrid-electric propulsion systems have emerged as a viable solution. In this paper a system based on hydrogen fuel cells is proposed and evaluated in a laboratory setting with its future integration in a propulsive system in mind and main focus on the ability to lessen the power demand on the opposing side of the bench. The setup consists in a parallel architecture with two power sources: a hydrogen fuel cell and a battery. First the performance of the fuel cell and its capability to provide power to one of the motors are analyzed. Then the entire parallel hybrid system is evaluated. Although the experimental setup was shown to be sub-optimal the results demonstrated the ability of this greener alternative to reduce power demand on the opposing side of the parallel configuration with a reduction of up to 40.3% in the highest load scenario and maximum power output on the fuel cell of 257.8 W. The stack performance was also concluded to be very dependent on the operating temperature.
The Impact of Sustainable Energy Technologies and Demand Response Programs on the Hub's Planning by the Practical Consideration of Tidal Turbines as a Novel Option
Apr 2023
Publication
This paper investigates a multi-objective optimal energy planning strategy for a hub incorporating renewable and non-renewable resources like PV tidal turbine fuel-cell CHP boiler micro-turbine reactor reformer electrolyzer and energy storage by utilizing the time of use program (TOU). In this strategy tidal turbine fuel-cell and reformer technologies are considered novel technologies that simultaneously reduce the proposed hub’s cost and pollution. The hub’s total cost and pollution are considered objective functions. To make the results more realistic characteristics of the tidal turbine are investigated by utilizing the manufactory’s company information. The problem is then modeled as real mixed integer programming (RMIP) and is solved in GAMS software using a CPLEX solver. Epsilon constraints method and fuzzy satisfying approach are used to select the optimal solution based on the proposed model. Finally a sensitivity analysis is performed to assess the effective parameters that affect the planning’s results. The results show that the overall pollution is reduced by about 9% by assuming the proposed planning and the total profit is increased by about 30%.
Biological Hydrogen Methanation with Carbon Dioxide Utilization: Methanation Acting as Mediator in the Hydrogen Economy
May 2023
Publication
Hydrogen is one of the main energy carriers playing a prominent role in the future decarbonization of the economy. However several aspects regarding the transport and storage of this gas are challenging. The intermediary conversion of hydrogen into high-density energy molecules may be a crucial step until technological conditions are ready to attain a significant reduction in fossil fuel use in transport and the industrial sector. The process of transforming hydrogen into methane by anaerobic digestion is reviewed showing that this technology is a feasible option for facilitating hydrogen storage and transport. The manuscript focuses on the role of anaerobic digestion as a technology driver capable of fast adaptation to current energy needs. The use of thermophilic systems and reactors capable of increasing the contact between the H2 -fuel and liquid phase demonstrated outstanding capabilities attaining higher conversion rates and increasing methane productivity. Pressure is a relevant factor of the process allowing for better hydrogen solubility and setting the basis for considering feasible underground hydrogen storage concomitant with biological methanation. This feature may allow the integration of sequestered carbon dioxide as a relevant substrate.
Microfluidic Storage Capacity and Residual Trapping During Cyclic Injections: Implications for Underground Storage
Apr 2023
Publication
Long-term and large-scale H2 storage is vital for a sustainable H2 economy. Research in underground H2 storage (UHS) in porous media is emerging but the understanding of H2 reconnection and recovery mechanisms under cyclic loading is not yet adequate. This paper reports a qualitative and quantitative investigation of H2 reconnection and recovery mechanisms in repeated injection-withdrawal cycles. Here we use microfluidics to experimentally investigate up to 5 cycles of H2 injection and withdrawal under a range of injection rates at shallow reservoir storage conditions. We find that H2 storage capacities increase with increasing injection rate and range between ~10% and 60%. The residual H2 saturation is in the same range between cycles (30e40%) but its distribution in the pore space visually appears to be hysteretic. In most cases the residually trapped H2 reconnects in the subsequent injection cycle predominantly in proximity to the large pore clusters. Our results provide valuable experimental data to advance the understanding of multiple H2 injection cycles in UHS schemes.
Rethinking "BELVE Explosion" After Liquid Hydrogen Storage Tank Rupture in a Fire
Sep 2022
Publication
The underlying physical mechanisms leading to the generation of blast waves after liquid hydrogen (LH2) storage tank rupture in a fire are not yet fully understood. This makes it difficult to develop predictive models and validate them against a very limited number of experiments. This study aims at the development of a CFD model able to predict maximum pressure in the blast wave after the LH2 storage tank rupture in a fire. The performed critical review of previous works and the thorough numerical analysis of BMW experiments (LH2 storage pressure in the range 2.0e11.3 bar abs) allowed us to conclude that the maximum pressure in the blast wave is generated by gaseous phase starting shock enhanced by combustion reaction of hydrogen at the contact surface with heated by the shock air. The boiling liquid expanding vapour explosion (BLEVE) pressure peak follows the gaseous phase blast and is smaller in amplitude. The CFD model validated recently against high-pressure hydrogen storage tank rupture in fire experiments is essentially updated in this study to account for cryogenic conditions of LH2 storage. The simulation results provided insight into the blast wave and combustion dynamics demonstrating that combustion at the contact surface contributes significantly to the generated blast wave increasing the overpressure at 3 m from the tank up to 5 times. The developed CFD model can be used as a contemporary tool for hydrogen safety engineering e.g. for assessment of hazard distances from LH2 storage.
Thermodynamic Evaluation and Carbon Footprint Analysis of the Application of Hydrogen-Based Energy-Storage Systems in Residential Buildings
Sep 2016
Publication
This study represents a thermodynamic evaluation and carbon footprint analysis of the application of hydrogen based energy storage systems in residential buildings. In the system model buildings are equipped with photovoltaic (PV) modules and a hydrogen storage system to conserve excess PV electricity from times with high solar irradiation to times with low solar irradiation. Short-term storages enable a degree of self-sufficiency of approximately 60% for a single-family house (SFH) [multifamily house (MFH): 38%]. Emissions can be reduced by 40% (SFH) (MFH: 30%) compared to households without PV modules. These results are almost independent of the applied storage technology. For seasonal storage the degree of self-sufficiency ranges between 57 and 83% (SFH). The emission reductions highly depend on the storage technology as emissions caused by manufacturing the storage dominate the emission balance. Compressed gas or liquid organic hydrogen carriers are the best options enabling emission reductions of 40%.
Simulation and Control Strategy Study of the Hydrogen Supply System of a Fuel Cell Engine
Jun 2023
Publication
The hydrogen supply system is one of the important components of a hydrogen fuel cell engine and its performance has an important impact on the economy and power of the engine system. In this paper a hydrogen supply system based on cyclic mode is designed for a hydrogen fuel cell stack with a full load power of 150 kW and the corresponding hydrogen fuel cell engine simulation model is built and validated. The control strategy of the fuel cell hydrogen supply system is developed and its effect is verified through bench tests. The results show that the developed control strategy can keep the volume fraction of nitrogen below 6% the hydrogen excess ratio does not exceed 1.5 under medium and high operating conditions the anode pressure is relatively stable and the stack can operate efficiently and reliably.
The Role of Liquid Hydrogen in Integrated Energy Systems - A Case Study for Germany
May 2023
Publication
Hydrogen (H2) is expected to be a key building block in future greenhouse gas neutral energy systems. This study investigates the role of liquid hydrogen (LH2) in a national greenhouse gas-neutral energy supply system for Germany in 2045. The integrated energy system model suite ETHOS is extended by LH2 demand profiles in the sectors aviation mobility and chemical industry and means of LH2 transportation via inland vessel rail and truck. This case study demonstrates that the type of hydrogen demand (liquid or gaseous) can strongly affect the cost-optimal design of the future energy system. When LH2 demand is introduced to the energy system LH2 import transportation and production grow in importance. This decreases the need for gaseous hydrogen (GH2) pipelines and affects the location of H2 production plants. When identifying no-regret measures it must be considered that the largest H2 consumers are the ones with the highest readiness to use LH2.
Energy Performance Assessment of a Solar-driven Thermochemical Cycle Device for Green Hydrogen Production
Sep 2023
Publication
This paper presents a novel dynamic simulation model for assessing the energy performance of solar-driven systems employed in green hydrogen production. The system consists of a parabolic dish collector that focuses solar radiation on two cerium-based thermochemical reactors. The model is based on a transient finitedifference method to simulate the thermal behaviour of the system and it integrates a theoretical analysis of materials and operating principles. Different empirical data were considered for experimentally validating it: a good agreement between experimental and simulated results was obtained for the temperatures calculated inside the thermochemical reactor (R2 = 0.99 MAPE = 6.3%) and the hourly flow rates of hydrogen oxygen and carbon monoxide (R2 = 0.96 MAPE = 10%) inside the thermochemical reactor. The model was implemented in a MatLab tool for the system dynamic analysis under different boundary conditions. Subsequently to explore the capability of this approach the developed tool was used for analysing the examined device operating in twelve different weather zones. The obtained results comprise heat maps of specific crucial instants and hourly dynamic trends showing redox reaction cycles occurring into the thermochemical reactors. The yearly hydrogen production ranges from 1.19 m3 /y to 1.64 m3 /y according to the hourly incident solar radiations outdoor air temperatures and wind speeds. New graphic tools for rapid feasibility studies are presented. The developed tools and the obtained results can be useful to the basic design of this technology and for the multi-objective optimization of its layout and main design/operating parameters.
Contribution to Net Zero Emissions of Integrating Hydrogen Production in Wastewater Treatment Plants
Jul 2023
Publication
The reliability of renewable hydrogen supply for off-take applications is critical to the future sustainable energy economy. Integrated water electrolysis can be deployed at distributed municipal wastewater treatment plants (WWTP) creating opportunity for reduction in carbon emissions through direct and indirect use of the electrolysis output. A novel energy shifting process where the co-produced oxygen is compressed and stored to enhance the utilisation of intermittent renewable electricity is analysed. The hydrogen produced can be used in local fuel cell electric buses to replace incumbent diesel buses for public transport. However quantifying the extent of carbon emission reduction of this conceptual integrated system is key. In this study the integration of hydrogen production at a case study WWTP of 26000 EP capacity and using the hydrogen in buses was compared with two conventional systems: the base case of a WWTP with grid electricity consumption offset by solar PV and the community’s independent use of diesel buses for transport and the non-integrated configuration with hydrogen produced at the bus refuelling location operated independently of the WWTP. The system response was analysed using a Microsoft Excel simulation model with hourly time steps over a 12-month time frame. The model included a control scheme for the reliable supply of hydrogen for public transport and oxygen to the WWTP and considered expected reductions in carbon intensity of the national grid level of solar PV curtailment electrolyser efficiency and size of the solar PV system. Results showed that by 2031 when Australia’s national electricity is forecast to achieve a carbon intensity of less than 0.186 kg CO2-e/kWh integrating water electrolysis at a municipal WWTP for producing hydrogen for use in local hydrogen buses produced less carbon emissions than continuing to use diesel buses and offsetting emissions by exporting renewable electricity to the grid. By 2034 an annual reduction of 390 t–CO2–e is expected after changing to the integrated configuration. Considering electrolyser efficiency improvements and curtailment of renewable electricity the reduction increases to 872.8 t–CO2–e.
Greenhouse Gas Reduction Potential and Cost-effectiveness of Economy-wide Hydrogen-natural Gas Blending for Energy End Uses
Sep 2022
Publication
North American and European jurisdictions are considering repurposing natural gas infrastructure to deliver a lower carbon blend of natural gas and hydrogen; this paper evaluates the greenhouse gas reduction potential and cost-effectiveness of the repurposing. The analysis uses a bottom-up economy-wide energy-systems model of an emission-intensive jurisdiction Alberta Canada to evaluate 576 long-term scenarios from 2026 to 2050. Many scenarios were included to give the analysis broad international applicability and differ by sector hydrogen blending intensity carbon policy and hydrogen infrastructure development. Twelve hydrogen production technologies are compared in a long-term greenhouse gas and cost analysis including advanced technologies. Autothermal reforming with carbon capture provides both lower-carbon and lower-cost hydrogen compared to most other technologies in most futures even with high fugitive natural gas production emissions. Using hydrogen-natural gas blends for end-use energy applications eliminates 1–2% of economy-wide GHG emissions and marginal GHG abatement costs become negative at carbon prices over $300/tonne. The findings are useful for stakeholders expanding the international low-carbon hydrogen economy and governments engaged in formulating decarbonization policies and are considering hydrogen as an option.
Evaluation of Surplus Hydroelectricity Potential in Nepal until 2040 and its Use for Hydrogen Production Via Electrolysis
May 2023
Publication
The abundant hydro resources in Nepal have resulted in the generation of electricity almost exclusively from hydropower plants. Several hydropower plants are also currently under construction. There is no doubt that the surplus electricity will be significantly high in the coming years. Given the previous trend in electricity consumption it will be a challenge to maximize the use of surplus electricity. In this work the potential solutions to maximize the use of this surplus electricity have been analysed. Three approached are proposed: (i) increasing domestic electricity consumption by shifting the other energy use sectors to electricity (ii) cross-border export of electricity and (iii) conversion of electricity to hydrogen via electrolysis. The current state of energy demand and supply patterns in the country are presented. Future monthly demand forecasts and surplus electricity projections have been made. The hydrogen that can be produced with the surplus electricity via electrolysis is determined and an economic assessment is carried out for the produced hydrogen. The analysis of levelized cost of hydrogen (LCOH) under different scenarios resulted values ranging from 3.8 €/kg to 4.5 €/kg.
Multi-Objective Robust Optimization of Integrated Energy System with Hydrogen Energy Storage
Feb 2024
Publication
A novel multi-objective robust optimization model of an integrated energy system with hydrogen storage (HIES) considering source–load uncertainty is proposed to promote the low-carbon economy operation of the integrated energy system of a park. Firstly the lowest total system cost and carbon emissions are selected as the multi-objective optimization functions. The Pareto front solution set of the objective function is applied by compromise planning and the optimal solution among them is obtained by the maximum–minimum fuzzy method. Furthermore the robust optimization (RO) approach is introduced to cope with the source–load uncertainty effectively. Finally it is demonstrated that the illustrated HIES can significantly reduce the total system cost carbon emissions and abandoned wind and solar power. Meanwhile the effectiveness of the proposed model and solution method is verified by analyzing the influence of multi-objective solutions and a robust coefficient on the Chongli Demonstration Project in Hebei Province.
A Techno-economic Study of the Strategy for Hydrogen Transport by Pipelines in Canada
Jan 2023
Publication
Hydrogen as a clean zero-emission energy fuel will play a critical role in energy transition and achievement of the net-zero target in 2050. Hydrogen delivery is integral to the entire value chain of a full-scale hydrogen economy. This work conducted a systematic review and analysis of various hydrogen transportation methods including truck tankers for liquid hydrogen tube trailers for gaseous hydrogen and pipelines by identifying and ranking the main properties and affecting factors associated with each method. It is found that pipelines especially the existing natural gas pipelines provide a more efficient and cheaper means to transport hydrogen over long distances. Analysis was further conducted on Canadian natural gas pipeline network which has been operating for safe effective and efficient energy transport over six decades. The established infrastructure along with the developed operating and management experiences and skillful manpower makes the existing pipelines the best option for transport of hydrogen in either blended or pure form in the country. The technical challenges in repurposing the existing natural gas pipelines for hydrogen service were discussed and further work was analyzed.
A Comprehensive Resilience Assessment Framework for Hydrogen Energy Infrastructure Development
Jun 2023
Publication
In recent years sustainable development has become a challenge for many societies due to natural or other disruptive events which have disrupted economic environmental and energy infrastructure growth. Developing hydrogen energy infrastructure is crucial for sustainable development because of its numerous benefits over conventional energy sources. However the complexity of hydrogen energy infrastructure including production utilization and storage stages requires accounting for potential vulnerabilities. Therefore resilience needs to be considered along with sustainable development. This paper proposes a decision-making framework to evaluate the resilience of hydrogen energy infrastructure by integrating resilience indicators and sustainability contributing factors. A holistic taxonomy of resilience performance is first developed followed by a qualitative resilience assessment framework using a novel Intuitionistic fuzzy Weighted Influence Nonlinear Gauge System (IFWINGS). The results highlighted that Regulation and legislation Government preparation and Crisis response budget are the most critical resilience indicators in the understudy hydrogen energy infrastructure. A comparative case study demonstrates the practicality capability and effectiveness of the proposed approach. The results suggest that the proposed model can be used for resilience assessment in other areas.
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