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Time is rapidly running out to make the crucial planning decisions and secure investment to keep the UK on track to deliver a reliable affordable and decarbonised energy system to meet future emissions regulation enshrined in the 2008 Climate Change Act according to a report published today by the Royal Academy of Engineering.

Prepared for the Prime Minister's Council for Science and Technology A critical time for UK energy policy details the actions needed now to create a secure and affordable low carbon energy system for 2030 and beyond.

The study looks at the future evolution of the UK’s energy system in the short to medium term. It considers how the system is expected to develop across a range of possible trajectories identified through modelling and scenarios.

The following actions for government are identified as a matter of urgency:

• enable local or regional whole-system large scale pilot projects to establish real-world examples of how the future system will work. These must move beyond  current single technology demonstrators and include all aspects of the energy systems along with consumer behaviour and financial mechanisms
• drive forward new capacity in the three main low carbon electricity generating technologies: nuclear carbon capture and storage (CCS) and offshore wind
• develop policies to accelerate demand reduction especially in domestic heating and introduce smarter demand management
• clarify and stabilise market mechanisms and incentives in order to give industry the confidence to invest.

New technologies could become unexpectedly significant – such as solar PV which has recently become much cheaper. But large scale deployment of novel technologies would take decades and the system cannot be planned on promises and aspirations alone. The Academy calls instead for a combination of known technologies to be scaled up to unprecedented levels and integrated in smarter ways.

The report notes that the addition of shale gas or tight oil is unlikely to have a major impact on the evolution of the UK's energy system as we already have secure and diverse supplies of hydrocarbons from multiple sources.

Dr David Clarke FREng who led the group that produced the report says: “Updating the UK energy system to meet the ‘trilemma’ of decarbonisation security and affordability is a massive undertaking. Meeting national targets affordably requires substantial decarbonisation of the electricity system by 2030 through a mix of nuclear power CCS and renewables with gas generation for balancing. Beyond 2030 we must then largely decarbonise heat and transport potentially through electrification but also using other options such as hydrogen and biofuels. We also need to adapt our transmission and distribution networks to become ‘smarter’”.

"Failure to plan the development of the whole energy system carefully will result at best in huge increases in the cost of delivery or at worst a failure to deliver. Substantial investment is needed and current investment capacity is fragile. For example in the last month projects like Carlton’s new Trafford CCGT plant have announced further financing delays and the hoped-for investment by Drax in the White Rose CCS demonstrator has been withdrawn. The UK has also dropped four places to 11th in EY’s renewable energy country attractiveness index.”

Link to document download on Royal Society Website

The current work is devoted to problems connected with application of CFD tools for safety analysis of large-scale industrial structures. With the aim to preserve conservatism of overall process of multistage procedure of such analysis special efforts are required. A strategy which has to lead to obtaining of reliable results in CFD analysis is discussed. Different aspects of proposed strategy including: adequate choice of physical and numerical models procedure of validation simulations and problem of ‘under-resolved’ simulations are considered. For physical phenomena which could cause significant uncertainties in the course of scenario simulation an approach which complements CFD simulations by application of auxiliary criteria is presented. Physical basis and applicability of strong flame acceleration and detonation-to-deflagration transition criteria are discussed. In concluding part two examples of application of presented approach for nuclear power plant and workshop cell for hydrogen driven vehicles are presented.

The present document is part of a larger literature survey of this WP aiming to establish the current status of gas utilisation technologies in order to determine the impact of hydrogen (H₂) admixture on natural gas (NG) appliances. This part focuses on the non-combustion related aspects of injecting hydrogen in the gas distribution networks within buildings including hydrogen embrittlement of metallic materials chemical compatibility and leakage issues. In the particular conditions of adding natural gas and hydrogen (NG / H2) mixture into a gas distribution network hydrogen is likely to reduce the mechanical properties of metallic components. This is known as hydrogen embrittlement (HE) (Birnbaum 1979). This type of damage takes place once a critical level of stress / strain and hydrogen content coexist in a susceptible microstructure. Currently four mechanisms were identified and will be discussed in detail. The way those mechanisms act independently or together is strongly dependent on the material the hydrogen charging procedure and the mechanical loading type. The main metallic materials used in gas appliances and gas distribution networks are: carbon steels stainless steels copper brass and aluminium alloys (Thibaut 2020). The presented results showed that low alloy steels are the most susceptible materials to hydrogen embrittlement followed by stainless steels aluminium copper and brass alloys. However the relative pressures of the operating conditions of gas distribution network in buildings are low i.e. between 30 to 50 mbar. At those low hydrogen partial pressures it is assumed that a gas mixture composed of NG and up to 50% H2 should not be problematic in terms of HE for any of the metallic materials used in gas distribution network unless high mechanical stress / strain and high stress concentrations are applied. The chemical compatibility of hydrogen with other materials and specifically polyethylene (PE) which is a reference material for the gas industry is also discussed. PE was found to have no corrosion issues and no deterioration or ageing was observed after long term testing in hydrogen gas. The last non-combustion concern related to the introduction of hydrogen in natural gas distribution network is the propensity of hydrogen toward leakage. Indeed the physical properties of hydrogen are different from other gases such as methane or propane and it was observed that hydrogen leaks 2.5 times quicker than methane. This bibliographical report on material deterioration chemical compatibility and leakage concerns coming with the introduction of NG / H₂ mixture in the gas distribution network sets the basis for the upcoming experimental work where the tightness of gas distribution network components will be investigated (Task 3.2.3 WP3). In addition tightness of typical components that connect end-user appliances to the local distribution line shall be evaluated as well.

The EC 6th framework research project HyApproval will draft a Handbook which will describe all relevant issues to get approval to construct and operate a Hydrogen Refuelling Station (HRS) for hydrogen vehicles. In WP3 of the HyApproval project it is under investigation which safety information competent authorities require to give a licence to construct an operate an HRS. The paper describes the applied methodology to collect the information from the authorities in 5 EC countries and the USA. The results of the interviews and recommendations for the information to include in the Handbook are presented.

Numerical simulations are carried out for a highly under-expanded hydrogen jet resulting from an accidental release of high-pressure hydrogen into the atmospheric environment. The predictions are made using two independent CFD codes namely CFX and KIVA. The KIVA code has been substantially modified by the present authors to enable large eddy simulation (LES). It employs a oneequation sub-grid scale (SGS) turbulence model which solves the SGS kinetic energy equation to allow for more relaxed equilibrium requirement and to facilitate high fidelity LES calculations with relatively coarser grids. Instead of using the widely accepted pseudo-source approach the complex shock structures resulting from the high under-expansion is numerically resolved in a small computational domain above the jet exit. The computed results are used as initial conditions for the subsequent hydrogen jet simulation. The predictions provide insight into the shock structure and the subsequent jet development. Such knowledge is valuable for studying the ignition characteristics of high-pressure hydrogen jets in the safety context.

This paper presents a beneficial combination of biomass gasification and pyrolysis oil hydrodeoxygenation for advanced biofuel production. Hydrogen for hydrodeoxygenation (HDO) of liquid phase pyrolysis oil (LPP oil) was generated by gasification of softwood. The process merges dual fluidized bed (DFB) steam gasification which produces a hydrogen rich product gas and the HDO of LPP oil. Synthesis gas was used directly without further cleaning and upgrading by making use of the water gas-shift (WGS) reaction. The water needed for the water gas-shift reaction was provided by LPP oil. HDO was successfully performed in a lab scale over 36 h time on stream (TOS). Competing reactions like the Boudouard reaction and Sabatier reaction were not observed. Product quality was close to Diesel fuel specification according to EN 590 with a carbon content of 85.4 w% and a residual water content of 0.28 w%. The water-gas shift reaction was confirmed by CO/CO₂-balance high water consumption and 28% less hydrogen consumption during HDO.

An essential problem for the operation of high pressure water electrolyzers and fuel cells is the permissible contamination of hydrogen and oxygen. This contamination can create malfunction and in the worst case explosions in the apparatus and gas cylinders. In order to avoid dangerous conditions the exact knowledge of the explosion characteristics of hydrogen/air and hydrogen/oxygen mixtures is necessary. The common databases e.g. the CHEMSAFE® database published by DECHEMA BAM and PTB contains even a large number of evaluated safety related properties among other things explosion limits which however are mainly measured according to standard procedures under atmospheric conditions.<br/>Within the framework of the European research project “SAFEKINEX” and other research projects the explosion limits explosion pressures and rates of pressure rise (KG values) of H2/air and H2/O2 mixtures were measured at elevated conditions of initial pressures and temperatures by the Federal Institute of Materials Research and Testing (BAM). Empirical equations of the temperature influence could be deduced from the experimental values. An anomaly was found at the pressure influence on the upper explosion limits of H2/O2 and H2/air mixtures in the range of 20 bars. In addition explosion pressures and also rates of pressure rises have been measured for different hydrogen concentrations inside the explosion range. Such data are important for constructive explosion protection measures. Furthermore the mainly used standards for the determination of explosion limits have been compared. Therefore it was interesting to have a look at the systematic differences between the new EN 1839 tube and bomb method ASTM E 681-01 and German DIN 51649-1.

The following report is a research piece outlining the potential pathways for decarbonisation of Scottish Industries. Two main pathways are considered hydrogen and electrification with both resulting in similar costs and levels of carbon reduction.

The report analyses the technical impacts to end-users of natural gas in Australian distribution networks when up to 10% hydrogen (by volume) is mixed with natural gas.



The full report can be found at this link.

We evaluated the strain rate sensitivity of the micro-damage evolution behavior in a ferrite/martensite dual-phase steel. The micro-damage evolution behavior can be divided into three regimes: damage incubation damage arrest and damage growth. All regimes are associated with local deformability. Thus the total elongation of DP steels is determined by a combination of plastic damage initiation resistance and damage growth arrestability. This fact implies that hydrogen must have a critical effect on the damage evolution because hydrogen enhances strain localization and lowers crack resistance. In this context the strain rate must be an important factor because it affects the time for microstructural hydrogen diffusion/segregation at a specific microstructural location or at the damage tip. In this study tensile tests were carried out on a DP steel with different strain rates of 10^{− 2} and 10^{− 4} s⁻¹. We performed the damage quantification microstructure characterization and fractography. Specifically the quantitative data of the damage evolution was analyzed using the classification of the damage evolution regimes in order to separately elucidate the effects of the hydrogen on damage initiation resistance and damage arrestability. In this study we obtained the following conclusions with respect to the strain rate. Lowering the strain rate increased the damage nucleation rate at martensite and reduced the critical strain for fracture through shortening the damage arrest regime. However the failure occurred via ductile modes regardless of strain rate.