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A Westminster Hall debate on the UK hydrogen economy has been scheduled for Thursday 17 December 2020 at 3.00pm. The debate will be led by Alexander Stafford MP. This House of Commons Library debate pack provides background information and press and parliamentary coverage of the issues.<br/><br/>The Government has legally binding targets under the Climate Change Act 2008 to reach ‘net zero’ carbon emissions by 2050. Background information is available from the Library webpage on Climate Change: an overview.<br/><br/>In order to meet the net zero target the use of fossil fuels (without abatement such as carbon capture usage and storage) across the economy will need to be almost entirely phased out by 2050. Hydrogen gas is regarded as an energy option to help decarbonisation especially in relation to applications that may be more challenging to decarbonise. These applications include heating transport (including heavy goods shipping and aviation) and some industrial processes.<br/><br/>The Government has legally binding targets under the Climate Change Act 2008 to reach ‘net zero’ carbon emissions by 2050. Background information is available from the Library webpage on Climate Change: an overview.<br/><br/>In order to meet the net zero target the use of fossil fuels (without abatement such as carbon capture usage and storage) across the economy will need to be almost entirely phased out by 2050. Hydrogen gas is regarded as an energy option to help decarbonisation especially in relation to applications that may be more challenging to decarbonise. These applications include heating transport (including heavy goods shipping and aviation) and some industrial processes.

Since the addition of Al to high-Mn steels is known to reduce their sensitivity to hydrogen-induced delayed fracture we investigate possible trapping effects connected to the presence of Al in the grain interior employing density-functional theory (DFT). The role of Al-based precipitates is also investigated to understand the relevance of short-range ordering effects. So-called E21-Fe3AlC κ-carbides are frequently observed in Fe-Mn-Al-C alloys. Since H tends to occupy the same positions as C in these precipitates the interaction and competition between both interstitials is also investigated via DFT-based simulations. While the individual H–H/C–H chemical interactions are generally repulsive the tendency of interstitials to increase the lattice parameter can yield a net increase of the trapping capability. An increased Mn content is shown to enhance H trapping due to attractive short-range interactions. Favorable short-range ordering is expected to occur at the interface between an Fe matrix and the E21-Fe3AlC κ-carbides which is identified as a particularly attractive trapping site for H. At the same time accumulation of H at sites of this type is observed to yield decohesion of this interface thereby promoting fracture formation. The interplay of these effects evident in the trapping energies at various locations and dependent on the H concentration can be expressed mathematically resulting in a term that describes the hydrogen embrittlement

In this work a low-temperature symmetrical solid oxide fuel cell with Ni-NCAL|SDC/NCAL|Ni-NCAL (70 SDC:30 NCAL) configuration was successfully constructed by a simple dry press method. At 500 and 550 ◦C the peak power densities of the cell in ammonia were 501 and 755 mW cm− 2 and in hydrogen were 670 and 895 mW cm− 2 respectively. EIS data showed that the Rp values of the cell in ammonia and hydrogen at 550 ◦C were 0.250 and 0.246 Ω cm− 2 respectively indicating the excellent catalytic activity of the Ni-NCAL electrode toward ammonia decomposition and hydrogen oxidation. The different cell output can be ascribed to additional ammonia decomposition steps compared to hydrogen. The noticeable reaction product on the surface of the Ni foam was detrimental to ammonia decomposition. In summary a symmetrical cell with SDC/NCAL semi-conductor electrolyte and Ni-NCAL electrodes exhibited higher electrochemical performance at low temperature than the results reported to date. Therefore higher electrochemical performance can be expected from this cell configuration with more efficient ammonia decomposition catalysts.

Hydrogen is an economical source of clean energy that has been utilized by industry for decades. In recent years demand for hydrogen has risen significantly. Hydrogen sources include water electrolysis hydrocarbon steam reforming and fossil fuels which emit hazardous greenhouse gases and therefore have a negative impact on global warming. The increasing worldwide population has created much pressure on natural fuels with a growing gap between demand for renewable energy and its insufficient supply. As a result the environment has suffered from alarming increases in pollution levels. Biohydrogen is a sustainable energy form and a preferable substitute for fossil fuel. Anaerobic fermentation photo fermentation microbial and enzymatic photolysis or combinations of such techniques are new approaches for producing biohydrogen. For cost-effective biohydrogen production the substrate should be cheap and renewable. Substrates including algal biomass agriculture residue and wastewaters are readily available. Moreover substrates rich in starch and cellulose such as plant stalks or agricultural waste or food industry waste such as cheese whey are reported to support dark- and photo-fermentation. However their direct utilization as a substrate is not recommended due to their complex nature. Therefore they must be pretreated before use to release fermentable sugars. Various pretreatment technologies have been established and are still being developed. This article focuses on pretreatment techniques for biohydrogen production and discusses their efficiency and suitability including hybrid-treatment technology

At present aero engine fault diagnosis is mainly based on the steady-state condition at the cruise phase and the gas path parameters in the entire flight process are not effectively used. At the same time high quality steady-state monitoring measurements are not always available and as a result the accuracy of diagnosis might be affected. There is a recognized need for real-time performance diagnosis of aero engines operating under transient conditions which can improve their condition-based maintenance. Recent studies have demonstrated the capability of the sequential model-based diagnostic method to predict accurately and efficiently the degradation of industrial gas turbines under steady-state conditions. Nevertheless incorporating real-time data for fault detection of aero engines that operate in dynamic conditions is a more challenging task. The primary objective of this study is to investigate the performance of the sequential diagnostic method when it is applied to aero engines that operate under transient conditions while there is a variation in the bypass ratio and the heat soakage effects are taken into consideration. This study provides a novel approach for quantifying component degradation such as fouling and erosion by using an adapted version of the sequential diagnostic method. The research presented here confirms that the proposed method could be applied to aero engine fault diagnosis under both steady-state and dynamic conditions in real-time. In addition the economic impact of engine degradation on fuel cost and payload revenue is evaluated when the engine under investigation is using hydrogen. The proposed method demonstrated promising diagnostic results where the maximum prediction errors for steady state and transient conditions are less than 0.006% and 0.016% respectively. The comparison of the proposed method to a benchmark diagnostic method revealed a 15% improvement in accuracy which can have great benefit when considering that the cost attributed to degradation can reach up to $702585 for 6000 flight cycles of a hydrogen powered aircraft fleet. This study provides an opportunity to improve our understanding of aero engine fault diagnosis in order to improve engine reliability availability and efficiency by online health monitoring.

HyNet North West is a significant clean growth opportunity for the UK. It is a low cost deliverable project which meets the major challenges of reducing carbon emissions from industry domestic heat and transport.<br/>HyNet North West is based on the production of hydrogen from natural gas. It includes the development of a new hydrogen pipeline; and the creation of the UK’s first carbon capture and storage (CCS) infrastructure. CCS is a vital technology to achieve the widespread emissions savings needed to meet the 2050 carbon reduction targets.<br/>Accelerating the development and deployment of hydrogen technologies and CCS through HyNet North West positions the UK strongly for skills export in a global low carbon economy.<br/>The North West is ideally placed to lead HyNet. The region has a history of bold innovation and today clean energy initiatives are thriving. On a practical level the concentration of industry existing technical skill base and unique geology means the region offers an unparalleled opportunity for a project of this kind.<br/>The new infrastructure built by HyNet is readily extendable beyond the initial project and provides a replicable model for similar programmes across the UK<br/>Contains Vision statement 2 leaflets a presentation and a summary report which are all stored as supplements.

We present a selection of scale transfer approaches from the electronic to the continuum regime for topics relevant to hydrogen embrittlement. With a focus on grain boundary related hydrogen embrittlement we discuss the scale transfer for the dependence of the carbon solution behavior in steel on elastic effects and the hydrogen solution in austenitic bulk regions depending on Al content. We introduce an approximative scheme to estimate grain boundary energies for varying carbon and hydrogen population. We employ this approach for a discussion of the suppressing influence of Al on the substitution of carbon with hydrogen at grain boundaries which is an assumed mechanism for grain boundary hydrogen embrittlement. Finally we discuss the dependence of hydride formation on the grain boundary stiffness

Today electricity & heat generation transportation and industrial sectors together produce more than 80% of energy-related CO₂ emissions. Hydrogen may be used as an energy carrier and an alternative fuel in the industrial residential and transportation sectors for either heating energy production from fuel cells or direct fueling of vehicles. In particular the use of hydrogen fuel cell vehicles (HFCVs) has the potential to virtually eliminate CO₂ emissions from tailpipes and considerably reduce overall emissions from the transportation sector. Although steam methane reforming (SMR) is the dominant industrial process for hydrogen production environmental concerns associated with CO₂ emissions along with the process intensification and energy optimization are areas that still require improvement. Metallic membrane reactors (MRs) have the potential to address both challenges. MRs operate at significantly lower pressures and temperatures compared with the conventional reactors. Hence the capital and operating expenses could be considerably lower compared with the conventional reactors. Moreover metallic membranes specifically Pd and its alloys inherently allow for only hydrogen permeation making it possible to produce a stream of up to 99.999+% purity.

For smaller and emerging hydrogen markets such as the semiconductor and fuel cell industries Pd-based membranes may be an appropriate technology based on the scales and purity requirements. In particular at lower hydrogen production rates in small-scale plants MRs with CCUS could be competitive compared to centralized H₂ production. On-site hydrogen production would also provide a self-sufficient supply and further circumvent delivery delays as well as issues with storage safety. In addition hydrogen-producing MRs are a potential avenue to alleviate carbon emissions. However material availability Pd cost and scale-up potential on the order of 1.5 million m3/day may be limiting factors preventing wider application of Pd-based membranes.

Regarding the economic production of hydrogen the benchmark by the year 2020 has been determined and set in place by the U.S. DOE at less than $2.00 per kg of produced hydrogen. While the established SMR process can easily meet the set limit by DOE other carbon-free processes such as water electrolysis electron beam radiolysis and gliding arc technologies do not presently meet this requirement. In particular it is expected that the cost of hydrogen produced from natural gas without CCUS will remain the lowest among all of the technologies while the hydrogen cost produced from an SMR plant with solvent-based carbon capture could be twice as expensive as the conventional SMR without carbon capture. Pd-based MRs have the potential to produce hydrogen at competitive prices with SMR plants equipped with carbon capture.

Despite the significant improvements in the electrolysis technologies the cost of hydrogen produced by electrolysis may remain significantly higher in most geographical locations compared with the hydrogen produced from fossil fuels. The cost of hydrogen via electrolysis may vary up to a factor of ten depending on the location and the electricity source. Nevertheless due to its modular nature the electrolysis process will likely play a significant role in the hydrogen economy when implemented in suitable geographical locations and powered by renewable electricity.

This review provides a critical overview of the opportunities and challenges associated with the use of the MRs to produce high-purity hydrogen with low carbon emissions. Moreover a technoeconomic review of the potential methods for hydrogen production is provided and the drawbacks and advantages of each method are presented and discussed.

In order to achieve gradual but timely decarbonisation of the transport sector it is essential to evaluate which types of vehicles provide a suitable environmental performance while allowing the use of hydrogen as a fuel. This work compares the environmental life-cycle performance of three different passenger cars fuelled by hydrogen: a fuel cell electric vehicle an internal combustion engine car and a hybrid electric vehicle. Besides two vehicles that use hydrogen in a mixture with natural gas or gasoline were considered. In all cases hydrogen produced by wind power electrolysis was assumed. The resultant life-cycle profiles were benchmarked against those of a compressed natural gas car and a hybrid electric vehicle fed with natural gas. Vehicle infrastructure was identified as the main source of environmental burdens. Nevertheless the three pure hydrogen vehicles were all found to be excellent decarbonisation solutions whereas vehicles that use hydrogen mixed with natural gas or gasoline represent good opportunities to encourage the use of hydrogen in the short term while reducing emissions compared to ordinary vehicles.

Hydrogen crossover rate is an important indicator for characterizing the membrane degradation and failure in proton exchange membrane fuel cell. Several electrochemical methods have been applied to quantify it. But most of established methods are too rough to support follow-up applications. In this paper a systematic and consistent theoretical foundation for electrochemical measurements of hydrogen crossover is established for the first time. Different electrochemical processes occurring throughout the courses of applying potentiostatic or galvanostatic excitations on fuel cell are clarified and the linear current–voltage behavior observed in the steady-state voltammogram is reinterpreted. On this basis we propose a modified galvanostatic charging method with high practicality to achieve accurate electrochemical measurement of hydrogen crossover and the validity of this method is fully verified. This research provides an explicit framework for implementation of galvanostatic charging method and offers deeper insights into the principles of electrochemical methods for measuring hydrogen crossover.