In June 2019, the House of Commons passed legislation to commit the UK to net-zero carbon emissions by 2050. With a third of UK greenhouse gases coming from our homes, it is crucial to overcome the challenge of home heating to meet climate change targets. As a potential low carbon alternative to natural gas, and the most abundant chemical on earth, hydrogen could be integral in the move towards zero carbon future solutions.
Whilst new homes and passively airtight built properties will be ideally served by low temperature appliances such as heat pumps, an alternative approach for the existing, difficult to treat, housing stock with gas boilers and conventional higher temperature heating circuits is required. A hydrogen boiler would work in a similar way to existing gas boilers but burns hydrogen as opposed to natural gas (methane). Hydrogen boilers would look and operate in a very similar way to a natural gas boiler and could offer a medium to long term option on heritage building stock.
Since 1996, the gas appliance directive has required all gas appliances to be tested with a blend of 23% hydrogen. The HyDeploy project at Keele University is a green energy trial that tested a campus of 100 dwellings and 30 faculty buildings which operated without fault on the blended fuel. A national distribution of blue or green blended hydrogen (hydrogen from either carbon capture or hydrogen from zero carbon sources) would save 6 million tonnes of CO2 per year. This blended fuel will also create a demand for the fuel to boost investment and drive the industry forward.
The latest 2020 Energy White Paper ‘Powering Our Net Zero Future’, states that hydrogen is to be part of the future fuel economy with 5GW of green hydrogen being produced by 2030. Hydrogen is currently produced by steam reformation and produces carbon – this ‘Blue Carbon’ is produced in one place and provides the opportunity to be caught or captured and stored rather than being emitted to the atmosphere nationwide as current gas boilers do.
The ultimate goal is to develop green hydrogen, produced by renewable energy, and scale this up. Until this is actionable, blue hydrogen (with carbon capture) has a place to create a demand and hydrogen economy within the UK. Hopefully by creating a demand, this will lead to further investment and demand for green hydrogen. In the meantime, there has been some major investment and research being undertaken into the safety and viability of replacing natural gas with hydrogen:
- Prototypes of hydrogen ready boilers have been produced by Baxi and Worcester Bosch and trialled and installed in research developments. These boilers can operate on natural gas or a natural gas/hydrogen blend and can easily be converted in the home to run on 100% hydrogen.
- Manufacturers, suppliers, and energy distributers are heavily involved in the testing of networks, compliance, and safety of hydrogen. SGN is developing a world-first hydrogen network for their H100 Fife project. Plans for this project are to construct a green hydrogen plant to serve community buildings and 300 dwellings, from hydrogen produced wind turbines in the North Sea. The demonstration facility is due to be built this year and the full project complete in 2027.
- EDF Energy’s new nuclear power station, Sizewell C, is planned to produce 1GW of green hydrogen from nuclear power to supply Felixstowe and Harwich as part of the Freeport East proposals by 2030.
- H21, a suite of gas industry projects, have built homes for the testing of appliances and systems served with 100% hydrogen to advise on safety standards and regulations that will be needed alongside the technology. Both Worcester Bosch and Baxi have their prototype hydrogen ready boilers installed at these sites. With these trials complete this year the government will be able to advise the future for hydrogen ready boilers.
The use of blue hydrogen, blended hydrogen and hydrogen ready boilers provide a pathway to the goal of a 100% green hydrogen network and a share in the UK zero carbon future. It must be noted that there will be no one ‘silver bullet’ that will solve the zero-carbon challenge, and multiple technology solutions will be part of the journey. Whilst the route is not yet fixed, there is no doubt that hydrogen will have a role to play in our future fuel economy and within the existing housing stock.