Hydrogen Boilers

How can hydrogen be used to heat your home?

In essence, hydrogen boilers work the same way as conventional gas boilers. A hydrogen-fueled boiler located inside your home is used to heat water for hot water and heating. The difference is that when hydrogen is burned the by-product is pure water, unlike natural gas which releases carbon dioxide.

Sounds simple, but there’s a problem. Hydrogen isn’t extracted from the ground like natural gas, it has to be produced. There are several ways of doing this, including the electrochemical process where the gas is extracted from a source fuel. And electrolysis which splits water (H2O) into its constituent parts, Hydrogen and Oxygen.

Hydrogen can either be produced off-site before being delivered via pipes, or it can be produced on-site using a hydrogen fuel cell. In both cases, however, energy needs to be used to create pure hydrogen. Where this energy comes from and how the resulting carbon emissions are contained will ultimately dictate how successful hydrogen will be at replacing gas.

The Hy4Heat(opens in a new window) project is currently exploring ways of replacing natural gas with hydrogen across the entire UK network.

Advantages of hydrogen

Environmentally friendly

Hydrogen boilers don’t release carbon dioxide as a by-product of the combustion process. This will greatly reduce the amount of CO2 released into the atmosphere each year.

Energy efficient

Hydrogen is energy-rich, every 1kg of hydrogen contains the same amount of energy as 2.8kg of gasoline. This makes it much more efficient to burn in your home which should reduce energy bills.

Greater storage potential

Hydrogen is one of the easiest gasses to store. Several storage options are available including compressed storage and liquid storage. The gas can also be stored as ammonia (NH3) which allows the gas to be stored and transported under safe conditions.

Can use the current infrastructure

One of the biggest benefits of using hydrogen is that it can be delivered to homes using the current gas infrastructure. This will greatly reduce the cost of making the change and it should speed up the process as well.

Disadvantages of hydrogen

Highly flammable

One of the biggest downsides of hydrogen is its high energy density which makes it highly flammable. This increases the risk of explosion during transport so extensive testing will be required to the systems in place are safe to use.

Existing appliances will need to be converted

While you won’t have to replace current gas appliances you will need to have them converted to use 100% hydrogen.

Hydrogen production may emit carbon

Producing hydrogen requires energy which will have to come from renewable sources if the fuel is to be considered a truly green alternative to gas. The use of solar energy or wind power could be the answer. Another alternative is to capture the carbon emissions created.

Heating engineers need to upskill

Due to the safety concerns of using hydrogen, heating engineers will have to update their skills to install hydrogen appliances and boilers.

When will hydrogen boilers become available?

Hydrogen is still an experimental technology which is not yet ready for mass-market deployment. Several 100% hydrogen-powered boilers are in development however from manufacturers such as Baxi and Worcester Bosch. But they will not become available until the technology is proved safe and the network rolls out mass hydrogen delivery.

In the meantime, the HyDeploy study(opens in a new window) from Keele University is looking at how hydrogen can be mixed with natural gas in the current network. A 12-month trial is currently underway using a mixture of 20% hydrogen 80% methane. This should cut carbon emissions and will not require homeowners to make any changes to their boilers or appliances.

What can I do to heat my home more efficiently now?

While you can’t yet buy a hydrogen boiler to reduce your carbon emissions there are several steps you can take to make your home more efficient today. Options include:

• Improving your insulation (loft and cavity wall)
• Installing a smart thermostat
• Upgrading to an A-rated boiler

You may be able to obtain a grant to make some of the above improvements to your home thanks to the government’s latest scheme ECO.

Please read our Government Boiler Grants Article for more information on the types of funding available and the home improvements you can make.

We’ve also put together some energy saving advice in our Energy Saving Tips Article, aimed to help you cut those energy bills whilst boosting your home’s energy efficiency.