Repurposed gas networks carrying hydrogen are set to be a crucial part of the journey to net zero, according to the Energy & Utilities Alliance (EUA).
On 21 April, the EUA published a report, Decarbonising heat in buildings: putting consumers first, where it warned that without a choice of different heat technologies for the UK housing stock, decarbonisation of heat will fail. Decarbonising heat for buildings is one of the “biggest challenges” for reaching net zero, with the residential sector emitting 65.2Mt of carbon dioxide (CO2) in 2019, or 19% of all CO2. Fossil fuels for heating and cooking are the main source of emissions in the residential sector – 85% (23mn) of homes connected to the gas grid, while 15% use oil or LPG as their main heating fuel or electric heating and over the next 10-15 years, the majority of these systems face having to be replaced.
Heat pumps, while important, should be supported by a “mosaic of heating solutions” that include a hydrogen gas network. Despite 7-10mn homes having no limiting factors to installation of a heat pump, the EUA found 37% to 54% (8-12mn) of homes using gas for heating will not be suitable and while 3-4mn could be made suitable through certain measures, the levels of disruption and association costs that would arise suggest they would be better served through a gas-based technology. Specifically, it called for a blend of locally specific solutions tailored to the needs of housing stock and other geographical features.
In some cases, it suggested that a combination of electrification and hydrogen could prove the best solution. This would see hybrid heat pumps used, combining a hydrogen boiler with an electrically driven heat pump. The hydrogen boiler, which can replace conventional gas ones on a like-for-like basis, has the potential to eliminate carbon emissions from heating completely with water the only by-product. Having a decarbonised gas network that carries hydrogen, which is zero carbon at point of use, will be key to supporting wider use of heat pumps, it added. This conversion can be done incrementally and with limited disruption to consumers.
The EUA highlighted how a number of trials conducted, focused on hydrogen as a potential option for decarbonising heat, have shown the technical and economic feasibility of such a conversion. This shows hydrogen as a heating fuel, alongside renewable gases ore broadly, are a crucial part of the journey to net zero. It called for the UK’s hydrogen ambitions to reflect this.