Heating produces one-quarter of the UK’s total carbon emissions. It is therefore vital that we develop more eco-friendly heating solutions if we are to reach the UK’s target of having net-zero carbon emissions by 2050.
80% of homes in the UK have gas central heating fuelled by fossil fuels. Many renewable technologies have been developed as an alternative (e.g. biomass boilers, heat pumps and solar thermal heating). These have great sustainability potential but the installation of these systems is often more suited to recently built, well-insulated properties. In the UK, the majority of residential properties are built before the 1980s. It would be difficult to implement some of these solutions in outmoded homes. A less disruptive alternative is to use the existing gas central heating system, but with a gas more environmentally friendly than natural gas: Hydrogen (H2).
How Hydrogen Boilers Work
Conventional boilers burn natural gas to heat cold water into hot water which then flows into radiators throughout the home. Natural gas burning produces various undesirable products including carbon monoxide (CO) and carbon dioxide (CO2). If instead, hydrogen is burned, only water vapour is produced and no carbon is released into the atmosphere.
Even a mix of 20% hydrogen 80% natural gas would significantly reduce carbon emissions. The HyDeploy project, funded by the UK government, is investigating this gas mixture by using it in existing pipelines and boilers to quantify the environmental benefits by summer 2020 (https://hydeploy.co.uk/).
Benefits of Hydrogen Gas
The main benefits of using hydrogen gas are the reduction in carbon emissions and that existing infrastructure does not have to be replaced. The UK has 176,469 miles of gas pipework connecting 23 million homes. If this existing asset is used for future energy solutions, disruption and monetary cost to homeowners can be minimised. In fact, the UK government is considering a proposal from the heating industry to set a date after which all new boilers must be sold as “hydrogen ready”, able to burn both natural and hydrogen gas from the mains gas pipeline.
Additionally, hydrogen is a very efficient fuel. The energy density by weight is three times that of gasoline or natural gas. It can also be produced by the electrolysis of water. This is a process that, if powered by electricity produced by wind, hydro or solar, can be self-sufficient with zero emissions. (Learn more: https://youtu.be/nA51Dq_lwZU.)
Once produced, hydrogen is easily stored in high-pressure tanks.
Challenges of Hydrogen Gas
Although hydrogen production is viable, it is currently only cost-competitive for niche industrial applications. It would be extremely expensive to produce large enough quantities to meet demand for UK domestic heating. The most common hydrogen production methods, such as steam methane reforming, emit carbon during the process. This is undesirable considering our push for net-zero carbon emissions.
The previously mentioned electrolysis process would require vast amounts of energy to produce sufficient hydrogen. However, this should be achievable in the future thanks to the falling costs of wind energy and research into electrolyser technology.
New Release from Worcester Bosch
In January, Worcester Bosch unveiled their new hydrogen boiler. Martin Bridges, Director of Technical Communication and Product Management, said:
“The development of hydrogen-fired boilers will mean millions of existing heating systems in our homes can be saved, rather than the entire system needing to be replaced.”
Worcester Bosch are committed to finding viable solutions to decarbonising UK heating. It is expected that other boiler manufacturers will follow suit. Worcester Bosch are providing hydrogen boilers to the UK Government Department for Business Energy and Industrial Strategy this year. Despite being ready for these trials, Worcester Bosch will wait a few years to release hydrogen boilers for general retail. This allows time for testing and development.
To find out more, visit: https://www.worcester-bosch.co.uk/professional/hydrogen-future-of-fuel.
The ThermaFY application is used to analyse thermal images of the radiators in a property and identify any issues affecting efficiency. Since hydrogen boilers only change the way water is heated in a heating system, existing water pipes and radiators can still be inspected in the same way as other central heating systems; ThermaFY surveys will continue to provide a detailed analysis of the whole heating system to ensure the system is running efficiently.