United Kingdom

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.

This review critically analyses various aspects of the most promising thermochemical cycles for clean hydrogen production. While the current hydrogen market heavily relies on fossil-fuel-based platforms the thermochemical water-splitting systems based on the reduction-oxidation (redox) looping reactions have a significant potential to significantly contribute to the sustainable production of green hydrogen at scale. However compared to the water electrolysis techniques the thermochemical cycles suffer from a low technology readiness level (TRL) which retards the commercial implementation of these technologies. This review mainly focuses on identifying the capability of the state-of-the-art thermochemical cycles to deploy large-scale hydrogen production plants and their techno-economic performance. This study also analyzed the potential integration of the hybrid looping systems with the solar and nuclear reactor designs which are evidenced to be more cost-effective than the electrochemical water-splitting methods but it excludes fossil-based thermochemical processes such as gasification steam methane reforming and pyrolysis. Further investigation is still required to address the technical issues associated with implementing the hybrid thermochemical cycles in order to bring them to the market for sustainable hydrogen production.

Engineering tools for calculation of hazard distances for cryogenic hydrogen jets are currently missing. This study aims at the development of validated correlations for calculation of hazard distances for cryogenic unignited releases and jet fires. The experiments performed by Sandia National Laboratories (SNL) on jets from storage temperature in the range 46-295 K and pressure up to 6 bar abs are used to expand the validation domain of the correlations. The Ulster’s under-expanded jet theory is applied to calculate parameters at the real nozzle exit. The similarity law for concentration decay in momentum-dominated jets is shown to be capable to reproduce experimental data of SNL on 9 unignited cryogenic releases. The accuracy of the similarity law to predict experimentally measured axial concentration decay improves with the increase of the release diameter. This is thought due to decrease of the effect of friction and minor losses for large release orifices. The dimensionless flame length correlation is applied to analyse 30 cryogenic jet fire tests. The deviation of calculated flame length from measured in experiments is mostly within acceptable accuracy for engineering correlations 20% similarly to releases from storage and equipment at atmospheric temperatures. It is concluded that the similarity law and the dimensionless flame correlation can be used as universal engineering tools for calculation of hazard distances for hydrogen releases at any storage temperature including cryogenic.

The final session of the meeting consisted of a discussion panel to propose future directions for research in the field of hydrogen embrittlement and the potential impact of this research on public policy.

This article is a transcription of the recorded discussion of ‘Hydrogen Embrittlement: Future Directions’ at the Royal Society Scientific Discussion Meeting Challenges of Hydrogen and Metals Jan 16th–18th 2017. The text is approved by the contributors. H.L. transcribed the session and drafted the manuscript. Y.C. assisted in the preparation of the manuscript.

Link to document download on Royal Society Website 

The bioanode is important for a microbial electrolysis cell (MEC) and its robustness to maintain its catalytic activity affects the performance of the whole system. Bioanodes enriched at a potential of +0.2 V (vs. standard hydrogen electrode) were able to sustain their oxidation activity when the anode potential was varied from -0.3 up to +1.0 V. Chronoamperometric test revealed that the bioanode produced peak current density of 0.36 A/m2 and 0.37 A/m2 at applied potential 0 and +0.6 V respectively. Meanwhile hydrogen production at the biocathode was proportional to the applied potential in the range from -0.5 to  -1.0 V. The highest production rate was 7.4 L H2/(m2 cathode area)/day at -1.0 V cathode potential. A limited current output at the bioanode could halt the biocathode capability to generate hydrogen. Therefore maximum applied potential that can be applied to the biocathode was calculated as -0.84 V without overloading the bioanode.

This work programme was focused on identifying a suitable odorant for use in a 100% hydrogen gas grid (domestic use such as boilers and cookers). The research involved a review of existing odorants (used primarily for natural gas) and the selection of five suitable odorants based on available literature. One odorant was selected based on possible suitability with a Polymer Electrolyte Membrane (PEM) based fuel cell vehicle which could in future be a possible end-user of grid hydrogen. NPL prepared Primary Reference Materials containing the five odorants in hydrogen at the relevant amount fraction levels (as would be found in the grid) including ones provided by Robinson Brothers (the supplier of odorants for natural gas in the UK). These mixtures were used by NPL to perform tests to understand the effects of the mixtures on pipeline (metal and plastic) appliances (a hydrogen boiler provided by Worcester Bosch) and PEM fuel cells. HSE investigated the health and environmental impact of these odorants in hydrogen. Olfactory testing was performed by Air Spectrum to characterise the ‘smell’ of each odorant. Finally an economic analysis was performed by E4tech. The results confirm that Odorant NB would be a suitable odorant for use in a 100% hydrogen gas grid for combustion applications but further research would be required if the intention is to supply grid hydrogen to stationery fuel cells or fuel cell vehicles. In this case further testing would need to be performed to measure the extent of fuel cell degradation caused by the non-sulphur odorant obtained as part of this work programme and also other UK projects such as the Hydrogen Grid to Vehicle (HG2V) project would provide important information about whether a purification step would be required regardless of the odorant before the hydrogen purity would be suitable for a PEM fuel cell vehicle. If purification was required it would be fine to use Odorant NB as this would be removed during the purification step.

This report and any attachment is freely available on the ENA Smarter Networks Portal here. IGEM Members can download the report and any attachment directly by clicking on the pdf icon above.

The hydrogen economy is a proposition for the distribution of energy by using hydrogen in order to potentially eliminate carbon emissions and end our reliance on fossil fuels. Some futuristic forecasters view the hydrogen economy as the ultimate carbon free economy. Hydrogen operated vehicles are on trial in many countries. The use of hydrogen as an energy source for buildings is in its infancy but research and development is evolving. Hydrogen is generally fed into devices called fuel cells to produce energy. A fuel cell is an electrochemical device that produces electricity and heat from a fuel (often hydrogen) and oxygen. Fuel cells have a number of advantages over other technologies for power generation. When fed with clean hydrogen they have the potential to use less fuel than competing technologies and to emit no pollution (the only bi-product being water). However hydrogen has to be produced and stored in the first instance. It is possible to generate hydrogen from renewable sources but the technology is still immature and the transformation is wasteful. The creation of a clean hydrogen production and distribution economy at a global level is very costly. Proponents of a world-scale hydrogen economy argue that hydrogen can be an environmentally cleaner source of energy to end-users particularly in transportation applications without release of pollutants (such as particulate matter) or greenhouse gases at the point of end use. Critics of a hydrogen economy argue that for many planned applications of hydrogen direct use of electricity or production of liquid synthetic fuels from locally-produced hydrogen and CO2 (e.g. methanol economy) might accomplish many of the same net goals of a hydrogen economy while requiring only a small fraction of the investment in new infrastructure. This paper reviews the hydrogen economy how it is produced and distributed. It then investigates the different types of fuel cells and identifies which types are relevant to the built environment both in residential and nonresidential sections. It concludes by examining what are the future plans in terms of implementing fuel cells in the built environment and discussing some of the needs of built environment sector.



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According to the UK’s Committee on Climate Change the economically efficient achievement of Government’s legally-binding carbon-reduction target will require full decarbonisation of all heat in buildings and the decarbonisation of most industrial heat over the next 20 to 30 years (BEIS 2018). This goliath task is not unprecedented. Indeed the scale of this transition is similar to the UK’s former transition from coal to natural gas heating. Albeit the rate of transition away from natural gas will certainly need to be greater than the rate of the transition toward natural gas to achieve net zero greenhouse gas emissions by 2050.<br/><br/>At present Government’s commitment stands in sharp contrast with its inaction on heat decarbonisation to date. Under pressure to progress this agenda Government has charged the Clean Heat Directorate with the task of outlining the process for determining the UK’s long-term heat policy framework to be published in the ‘Roadmap for policy on heat decarbonisation’ in the summer of 2020 (BEIS 2017). This report resulting from one of six EPSRC-funded secondments is designed to support early thinking on the roadmap by answering the research question: How can ‘Transitions’ research informs the roadmap for governing the UK’s heating transition?<br/><br/>‘Transitions’ research is an interdisciplinary field of study within the Social Sciences and Humanities that investigates the co-evolution of social and technological systems (such as the UK heating system) and the dynamics by which fundamental change in these systems occur. To investigate what insights this area of research may hold for the governance of the UK’s heat transition a systematic literature review was conducted focusing specifically on past and ongoing heat transitions across Europe.<br/><br/>The review uncovered learnings about the role of path dependency; power and politics; complexity; cross-sector interactions; multi-level governance; and intermediaries in shaping non-linear transitions toward renewable heat. This report illustrates each learning with real-world examples from case studies undertaken by Transitions researchers and concludes with a long list of policy and process-oriented governance recommendations for the UK Government.

Magnesium hydride owns the largest share of publications on solid materials for hydrogen storage. The “Magnesium group” of international experts contributing to IEA Task 32 “Hydrogen Based Energy Storage” recently published two review papers presenting the activities of the group focused on magnesium hydride based materials and on Mg based compounds for hydrogen and energy storage. This review article not only overviews the latest activities on both fundamental aspects of Mg-based hydrides and their applications but also presents a historic overview on the topic and outlines projected future developments. Particular attention is paid to the theoretical and experimental studies of Mg-H system at extreme pressures kinetics and thermodynamics of the systems based on MgH₂ nanostructuring new Mg-based compounds and novel composites and catalysis in the Mg based H storage systems. Finally thermal energy storage and upscaled H storage systems accommodating MgH₂ are presented.

This session contained talks on the characterization of hydrogen-enhanced corrosion of steels and nickel-based alloys emphasizing the different observations across length scales from atomic-scale spectrographic to macro-scale fractographic examinations.

This article is the transcription of the recorded discussion of the session ‘Hydrogen Effects in Corrosion’ at the Royal Society discussion meeting Challenges of Hydrogen and Metals 16–18 January 2017. The text is approved by the contributors. M.A.S. transcribed the session and E.L.S. assisted in the preparation of the manuscript.

Link to document download on Royal Society Website