Network

NETWORK / 24 / APRIL/MAY 2020 ZERO CARBON GAS NGN: H21 The H21 project began in Leeds as a feasibility study, establishing that it was both technically possible and economically viable to convert the gas distribution network of a city the same size and energy demand as Leeds. But without a robust safety case to underpin it, no government policy decision around hydrogen's use for domestic heat will materialise. H21 therefore shifted from desktop study into heavyweight research and demonstration project to provide government with this essential data on the network. Supported by the RIIO Network Innovation Competition (NIC), the H21 NIC project has focused on delivering the essential critical safety evidence: proving that a 100% hydrogen network was of no greater risk than the natural gas network currently heating homes and fuelling industry today. Phase One Backed by all Gas Distribution Networks in collaboration with the Health & Safety Executive and DNV-GL Phase One has centred around two main workstreams since the start of 2018: Phase 1a: testing on a bespoke facility at the Health and Safety Executive's Science Division in Buxton, covering the huge range of metallic and PE assets, valves, joints, fittings and pipes across the UK. Phase 1b: consequence testing at DNV-GL's rig up at RAF Spadeadam, in Cumbria, measuring the risk associated with background leakage from Phase 1a, such as failure leakage, mains fracture, third party damage and operational repairs. This will establish the consequences of leaking hydrogen, such as tracking and dispersion, in scenarios with different potential sources of ignition, and comparing them to those of natural gas. In addition to the two key phases, the H21 NIC project is also delivering a Quantitative Risk Assessment (QRA) and Master Testing Plan (MTP). The QRA will be used to update the computer-based modelling systems for natural gas to 100% hydrogen applications, while the MTP was finalised for both sites' testing regimes, to ensure credibility, and that tests were undertaken in accordance with agreed methodology. Results from Phase One will be shared in a full report this summer. Phase Two Phase Two will see National Grid and Leeds Beckett University join the project consortia. It will involve simulating network operations on a specially constructed mini network in Spadeadam, continuing to use the site deployed for Phase One of H21. Network research trials will also be undertaken, to demonstrate operational and maintenance procedures - an essential prerequisite to live trials and will to take place on a decommissioned part of the gas network. A combined Quantitative Risk Assessment will bring together findings from the network testing and that of the Hy4Heat programme, currently exploring hydrogen's use in buildings and appliances. SGN: H100 Fife 100% hydrogen network H100 Fife is part of the national hydrogen programme and a key step on the pathway to decarbonisation. The project will involve constructing and operating a system that supplies zero-carbon hydrogen-to-homes for heating through a new network in Fife, Scotland. SGN has submitted an initial bid into Ofgem's Network Innovation Competition (NIC) to deliver the project, with the outcome expected to be announced later in the year. SGN, which runs the gas distribution networks in Scotland and Southern England, believes H100 Fife will be the world's first 100% hydrogen gas network if it is awarded funding. The demonstration will validate the extensive hydrogen research base that has been collaborated on nationally and show how hydrogen can play a critical role in the UK's low carbon future. Hydrogen will be produced at an electrolysis plant, primarily powered using clean electricity generated by a nearby offshore wind turbine. The gas will be safely stored in six above ground storage tanks operating at 30bar, which will ensure 5 days' security of supply. The storage will feed a new polyethylene pipe distribution network, which will be laid in parallel to the existing gas network. The project will test customer appetite and interest for hydrogen. Participation will be on an opt-in basis, meaning that customers within the network area will have the choice to switch to hydrogen, or remain with their existing supply. The demonstration facility component of the project will allow customers to interact with hydrogen appliances in a home-like setting. Phase 1 will connect 300 homes initially, which will be fitted with like for like hydrogen ready appliances under the project. Cadent: Future Biogas, Doncaster Green gas made from locally grown farming break-crops including maize, grass and other biomass will fuel thousands of homes and businesses across Yorkshire with the region's very first commercial gas to grid project at Lindholme, near Doncaster, commenced in 2014 The state of the art facility was the first biomethane plant to be built and operated by Future Biogas, and processes 35,000 tonnes of feedstock, sourced from local farmers each year. The farm break crops are fermented in an anaerobic digester to produce biogas, which consists of 60% methane. Volume and energy value of the biomethane is then measured to ensure it meets the requirements of the gas network before being injected. The plant can produce up to 12,000 cubic meters of biogas per day – enough to heat 2,500 homes during peak demand in winter. As a by-product, the process also produces a valuable organic fertiliser that will be used by the local farming community. Cadent is now working with Future Biogas to enable the site to inject more biomethane into its network. G A S G O E S G R E E N : C A S E S T U D I E S H100 Fife end to end hydrogen system. DECARBONISATION OF HEAT

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