United Kingdom

This paper describes a 1-D numerical model for the prediction of heat and mass transfer through an intumescent paint that is applied to an on-board high-pressure GH2 storage tank. The intumescent paint is treated as a composite system consisting of three general components decomposing in accordance with independent finite reaction rates. A moving mesh that is employed for a better prediction of the expansion process of the intumescent paint is based on the local changes of heat and mass. The numerical model is validated against experiments by Cagliostro et al. (1975). The overall model results are used to estimate effect of intumescent paint on fire resistance of carbon-fibre reinforced GH2 storage.

The HyDeploy Project seeks to address a key issue for UK customers: how to reduce the carbon they emit in heating their homes. The UK has a world class gas grid delivering heat conveniently and safely to over 83% of homes. Emissions could be reduced by lowering the carbon content of gas through blending with hydrogen. Compared with solutions such as heat pumps this means that customers would not need disruptive and expensive changes in their homes. This Network Innovation Competition (NIC) funded project seeks to establish the level of hydrogen that can be safely blended with natural gas for transport and use in a UK network.

Under its Smart Energy Network Demonstration innovation programme Keele University is establishing its electricity and gas networks as facilities to drive forward innovation in the energy sector. The objective of HyDeploy is to trial natural gas blended with potentially up to 20% volume of hydrogen in a part of the Keele gas network. Before any hydrogen can be blended with natural gas in the network the percentage of hydrogen to be delivered must be approved by the Health and Safety Executive (HSE). It must be satisfied that the approved blended gas will be as safe to use as normal gas. Any approval will be given as an exemption to the Gas Safety (Management) Regulations. These regulations ensure the safe use and management of gas through the gas network in the UK. The evidence presented to the HSE comprises critically appraised literature combined with the results from a specifically commissioned experimental and testing programme. Based on engagement with all local customers this includes detailed safety checks on the network appliances and installations at Keele. Subject to approval by the HSE the hydrogen production and grid injection units will be installed and an extensive trial programme of blending will be undertaken. If hydrogen were blended at 20% volume with natural gas across the UK it would save around 6 million tonnes of carbon dioxide emissions every year the equivalent of taking 2.5 million cars off the road.

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Fuel Cell Vehicles (FCVs) are a disruptive innovation and are currently looking towards niche market entry. However commercialisation has been unsuccessful thus far and there is a limited amount of literature that can guide their market entry. In this paper a historical case study is undertaken which looks at Tesla Motors high-end encroachment market entry strategy. FCVs have been compared to Tesla vehicles due to their similarities; both are disruptive innovations both are high cost and both are zero emission vehicles. Therefore this paper looks at what can be learned form Tesla Motors successful market entry strategy and proposes a market entry strategy for FCVs. It was found that FCVs need to enact a paradigm shift from their current market entry strategy to one of high-end encroachment. When this has been achieved FCVs will have greater potential for market penetration.

As the UK’s largest emitter of greenhouse gases the supply of domestic industrial and commercial heat must be decarbonised if the UK is to meet its climate change targets.<br/><br/>This report publishes the outcomes from Phase 1 of the Energy Technologies Institute’s Smart Systems and Heat programme highlighting that for the UK to transition to a low carbon heating system it must understand consumer needs and behaviours while connecting this with the development and integration of technologies and new business models.<br/><br/>Written by the ETI with support from the Energy Systems Catapult this report tackles three interconnected areas: heating needs and controls within the home; heating infrastructure and building retrofit at a local level; and the operation and governance of the whole system.<br/><br/>The research also shows that as part of a low carbon heating system upgrade advanced controls are critical to performance sizing and operating costs enabling smaller appliances and lower peak electricity demands and maximising the efficiency of existing infrastructure. With significant fabric retrofits potentially required in around 10 million of the existing 28 million dwellings in the UK housing stock the report recommends that building new homes to be both very efficient and “low carbon ready” is a low regret decision which should be progressed with some urgency.

In recent years new-found interest in the hydrogen economy from both industry and academia has helped to shed light on its potential. Hydrogen can enable an energy revolution by providing much needed flexibility in renewable energy systems. As a clean energy carrier hydrogen offers a range of benefits for simultaneously decarbonizing the transport residential commercial and industrial sectors. Hydrogen is shown here to have synergies with other low-carbon alternatives and can enable a more cost-effective transition to de-carbonized and cleaner energy systems. This paper presents the opportunities for the use of hydrogen in key sectors of the economy and identifies the benefits and challenges within the hydrogen supply chain for power-to-gas power-to-power and gas-to-gas supply pathways. While industry players have already started the market introduction of hydrogen fuel cell systems including fuel cell electric vehicles and micro-combined heat and power devices the use of hydrogen at grid scale requires the challenges of clean hydrogen production bulk storage and distribution to be resolved. Ultimately greater government support in partnership with industry and academia is still needed to realize hydrogen's potential across all economic sectors.

Link to document download on Royal Society Website

This study is driven by the need to understand requirements to safe blow-down of hydrogen onboard storage tanks through a pressure relief device (PRD) inside a garage-like enclosure with low natural ventilation. Current composite tanks for high pressure hydrogen storage have been shown to rupture in 3.5–6.5 min in fire conditions. As a result a large PRD venting area is currently used to release hydrogen from the tank before its catastrophic failure. However even if unignited the release of hydrogen from such PRDs has been shown in our previous studies to result in unacceptable overpressures within the garage capable of causing major damage and possible collapse of the structure. Thus to prevent collapse of the garage in the case of a malfunction of the PRD and an unignited hydrogen release there is a clear need to increase blow-down time by reducing PRD venting area. Calculations of PRD diameter to safely blow-down storage tanks with inventories of 1 5 and 13 kg hydrogen are considered here for a range of garage volumes and natural ventilation expressed in air changes per hour (ACH). The phenomenological model is used to examine the pressure dynamics within a garage with low natural ventilation down to the known minimum of 0.03 ACH. Thus with moderate hydrogen flow rate from the PRD and small vents providing ventilation of the enclosure there will be only outflow from the garage without any air intake from outside. The PRD diameter which ensures that the pressure in the garage does not exceed a value of 20 kPa (accepted in this study as a safe overpressure for civil structures) was calculated for varying garage volumes and natural ventilation (ACH). The results are presented in the form of simple to use engineering nomograms. The conclusion is drawn that PRDs currently available for hydrogen-powered vehicles should be redesigned along with either a change of requirements for the fire resistance rating or innovative design of the onboard storage system as hydrogen-powered vehicles are intended for garage parking. Further research is needed to develop safety strategies and engineering solutions to tackle the problem of fire resistance of onboard storage tanks and requirements to PRD performance. Regulation codes and standards in the field should address this issue.

Conditions are examined under which mechanical stimuli produced by striking controlled blows can result in sparking and ignition of hydrogen in air mixtures. The investigation principally concerns magnesium thermite reaction as the ignition source and focuses on the conditions and thermomechanical parameters that are involved in determining the probability of ignition. It is concluded that the notion of using the kinetic energy of impact as the main criterion in determining whether an ignition event is likely or not is much less useful than considering the parameters which determine the maximum temperature produced in a mechanical stimuli event. The most influential parameter in determining ignition frequency or probability is the velocity of sliding movement during mechanical stimuli. It is also clear that the kinetic energy of a moving hammer head is of lesser importance than the normal force which is applied during contact. This explains the apparent discrepancy in previous studies between the minimum kinetic energy thought to be necessary to allow thermite sparking and gas ignition to occur with drop weight impacts and glancing blow impacts. In any analysis of the likelihood of mechanical stimuli to cause ignition the maximum surface temperature generated should be determined and considered in relation to the temperatures that would be required to initiate hot surface reactions sufficient to cause sparking and ignition.

The next decade will see fundamental changes in how people heat their homes. The global energy system is changing in response to the need to transition away from fossil-based generation towards more environmentally sustainable alternatives.

Hydrogen offers one such alternative but currently there is limited understanding of public perceptions of hydrogen the information that people need in order to make an informed choice about using hydrogen in their homes and how misunderstandings could present barriers to the uptake of hydrogen technology. This is crucial to ensure the success of future policy and investment. The H21 concept is to convert the UK gas distribution network to 100% hydrogen over time thereby decarbonising heat and supporting decarbonisation of electric large industrials and transport. This would be achieved using the existing UK gas grid network and technology available across the world today whilst maintaining the benefits of gas and the gas networks in the energy mix for the long-term future. Additionally this would maintain choice of energy for customers i.e. they would be able to use both gas and electricity. The H21 project is being delivered by the UK gas distribution networks Northern Gas Networks Cadent Wales & West Utilities and SGN. As part of the H21 project Leeds Beckett University has been working with Northern Gas Networks to gain insight into public perceptions of hydrogen as a domestic fuel. Using innovative social science methods the research team has explored for the first time public perceptions of moving the UK domestic fuel supply to 100% hydrogen. We identify what people think and feel about a potential conversion the concerns and questions that they have and how to address them clearly. The findings presented in this report will ensure that issues around the current perception of hydrogen are identified and addressed prior to any large-scale technology rollout.

The first stage of the project comprised a series of discovery interviews which explored how to talk to people about hydrogen and the H21 project. We interviewed 12 participants selected to ensure we included people with a range of experiences and domestic settings for example people who live in urban and rural areas those who live alone those who live with children or a partner those who live in their own home and those who rent. Most participants had given very little thought about where their gas and electric comes from and other than switching supplier to get a better tariff had very little interest in it. They had not previously considered their domestic heating as a source of carbon emissions and were surprised that there may be a need in the future to change their gas supply. From the discovery interviews we identified several key areas to explore in the next stage of the work:

• Beliefs about the environment
• Beliefs about inconvenience and cost
• Beliefs about safety
• Beliefs about the economic impact

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.

Bioenergy with carbon capture and storage (BECCS) removes carbon dioxide (CO2) from the atmosphere i.e. negative CO2 emissions. It will likely have an important role in the transition to a net-zero economy by offsetting hard-to-abate greenhouse gas emissions. However there are concerns about the sustainability of large scale BECCS deployment using bioenergy from predominantly primary biomass sources (i.e. dedicated energy crops). Secondary sources of biomass (e.g. waste biomass municipal solid wastes forest/agricultural residues) are potentially an economical and sustainable alternative resource. Furthermore supplementing primary biomass demand with secondary sources could enable the supply of biomass from solely indigenous sources (i.e. from the UK) which could provide economic advantages in a growing global bio-economy.<br/><br/>There is also a growing interest in biomass-derived hydrogen production with CCS (BHCCS) which generates hydrogen and removes CO2 from the atmosphere. Hydrogen could help decarbonise fuel-dependent sectors such as heat industry or transportation. The aim of this study was to determine whether BHCCS could possibly deliver net negative CO2 emissions making comparisons against the other BECCS technologies.

This paper describes a CFD study of a scenario involving the vertical downward release of hydrogen from a thermally-activated pressure relief device (TPRD) under a fuel cell car. The volumetric source model is applied to simulate hydrogen release dynamics during the tank blowdown process. Simulations are conducted for both unignited and ignited releases from onboard storage at 35 MPa and 70 MPa with TPRD orifice 4.2 mm. Results show that after TPRD opening the hazards associated with the release of hydrogen lasts less than two minutes and the most hazardous timeframe occurs within ten seconds of the initiation of the release. The deterministic separation distances for unignited releases are longer than those for ignited releases indicating that the separation distances are dominated by delayed ignition events rather than immediate ignition events. The deterministic separation distances for both unignited and ignited hydrogen downward releases under the car are significantly shorter than those of free jets. To ensure the safety of people a deterministic separation distance of at least 10 m for 35 MPa releases is required. This distance should be increased to 12 m for the 70 MPa release case. To ensure that the concentration of hydrogen is always less than 4% at the location of the air intake of buildings the deterministic separation distance should be at least 11 m for 35 MPa releases and 13 m for 70 MPa releases.