Hydrogen in buildings
Hydrogen can be burnt in boilers for domestic or light commercial use. Today, Vaillant already offers boilers that can burn a mixture of hydrogen and natural gas. In the UK, the journey to fully decarbonised heating systems is a long term vision, but in an effort to lower carbon emissions on the way to a full hydrogen infrastructure, networks are currently being tested to supply a mixture of up to 20% hydrogen with natural gas. A blend of 20% hydrogen mixed with natural gas could give us a saving of up to 7% CO2 when using green hydrogen. But, to have a fully powered hydrogen network the infrastructure must be switched over, by means of a gas conversion programme.
As part of the 10-point plan announced by the Prime Minister on 18th November, the government have set the aim of producing a hydrogen heated neighbourhood by 2023, a village by 2025 and a town by the end of the decade.
(source https://www.gov.uk/government/news/pm-outlines-his-ten-point-plan-for-a-green-industrial-revolution-for-250000-jobs )
How heating with hydrogen works
The main appliance components as we know today will remain, with the necessary adaptation to operate with hydrogen. Key development challenges are aspects of flame detection, flashback prevention, gas-air control, condensate management, materials compatibility and H2-gas tightness.
Vaillant is developing hydrogen burning appliances which look and feel the same as today’s boilers, eliminate CO2 emissions, and have better NOx performance. The hydraulic components within the hydrogen boiler will also be the same as today, the only change will be with the combustion cell.
Hydrogen compared to today’s boilers
- Sizing: The appliances will have very similar shape, size and weight as today’s appliances, facilitating the replacement of the old appliances.
- Usage: The appliances will be connected to the same heating distribution system in the house (radiators, floor heating) and will fulfil the same functions as todays appliances (Space heating and DHW production, in one unit or with the support of external DHW storage)
- Efficiency: The efficiency level of H2 appliances will be comparable to the current condensing appliances.
Hydrogen and Heat Pumps - what´s the future technology?
We know there is no single solution to heating our homes and we will require a mix of technologies to manage the energy transition successfully. Green gases such as hydrogen will be part of the mix.
- Heat pumps and hydrogen boilers will most likely be the devices that will heat and produce domestic hot water for our homes and offices for decades to come.
- These two technologies will coexist because both will offer their best assets under very specific conditions of use, with their specific limits and advantages.