#H2Explainer: How safe will hydrogen be in our homes?

Whatever exciting potential hydrogen might hold for reducing our carbon emissions, Britain’s energy networks have one overriding priority – safety.

And as we set out earlier this year, Britain’s gas networks are committed to ensuring that the way Britain’s gas grid delivers hydrogen to our front doors is either as safe or even safer than the way it delivers methane natural gas today. Our approach is designed to build the ‘evidence-base’ for what changes need to be made to fulfil that commitment, over time and working closely with the Health & Safety Executive (HSE).

What is Hy4Heat?

In July, the Department of Business, Energy & Industrial Strategy announced the outcomes of a 3.5-year long hydrogen innovation project, called Hy4Heat, part of which looked at the safety of using hydrogen inside homes. Hy4Heat has carried out hundreds of tests comparing hydrogen and methane, and assessed the results of the new evidence.

What has its research concluded?

This Safety Assessment found that with some relatively small changes to the gas pipes used to transport hydrogen from the gas grid into a home, hydrogen can be as safe as the natural gas-based system we use today. 

The research examined how a home supplied with 100% hydrogen would behave if it continued to use the same types of gas pipes and safety measures that are installed in our homes right now, which are designed for methane natural gas, so we have a better understanding of what changes will need to be made in the future.

It found that by simply installing two ‘excess flow valves’ in the pipes carrying gas around a home, we can easily regulate how hydrogen flows through those pipes. As the name implies, these valves can automatically restrict the flow of hydrogen in and around the home in the event of a gas leak, to ensure that it remains within safe but usable limits, reducing the potential for an incident that might lead to injury.

The research also found with these valves installed and using 100% hydrogen in homes, the number of people injured would drop even lower than it is today, demonstrating that hydrogen can be safer than natural gas with some minor changes.

What do the recommendations mean?

These recommended changes were reviewed by the HSE, which is the Government body responsible for the safety of the gas networks, and they agreed with the findings and the recommendations of the Hy4Heat research. These recommendations will be mandatory in proposed community demonstrations of hydrogen networks, such as the Hydrogen Neighbourhood, Village and Town Trials announced in the Prime Minister’s Ten Point Plan, ensuring that public safety is maintained.

It’s also worth noting that because the research was a comparison of fire and explosion risks, it didn’t include further risk reductions associated with hydrogen. Because hydrogen doesn’t include carbon, it also eliminates the possibility of carbon monoxide poisoning that can come from older natural gas boilers that haven’t been serviced properly.

So, what next?

Gas network innovation projects and Hy4Heat continue to break new ground in this vital area, including through the first Hydrogen Village Trial. Crucially, they are building on the decades of testing and learning that have made the delivery of gas and electricity to homes as safe as it is today and identifying how we make it even safer as we look to new sources of energy to reduce our carbon emissions, reflecting how tomorrow’s heat is today’s opportunity.