Hydrogen boilers: everything you need to know
You might have heard that the UK’s gas supply is switching to hydrogen – and that the gas boilers we currently use will eventually be phased out.
But what does that mean for you and your home? And does it mean you’ll have to fork out for a completely new kind of boiler?
In this article, we’ll bring you up to speed with the latest plans. We’ll explain why it’s happening, when the changes are likely to start – and why it’s good news for everyone.
Are gas boilers being banned soon?
Short answer: no, not really.
You might have seen headlines about natural gas boilers being banned from 2025. But that’s just for new-build properties, not for existing homes and boilers.
In fact, as you’ll see from the estimated timescales below, a boiler you buy today will probably use natural gas for all its working lifetime.
After that, the two main ways to heat your home will be with a Heat Pump or with a boiler that runs – at least partly – on hydrogen.
The big switch to hydrogen
The UK government is planning to replace natural gas with hydrogen gas – because it’s much more environmentally friendly.
But this change will happen gradually over years, rather than all at once. And that means it shouldn’t be extra hassle or expense for homeowners. In fact, some of the biggest boiler manufacturers in the UK have promised that hydrogen-ready boilers won’t cost any more than a regular gas-powered boiler.
Nobody knows the exact timescales, and a lot of the technical details still need to be ironed out, but the change is likely to happen in three main stages.
Stage 1
New boilers will be built to a new ‘hydrogen-ready’ standard, which means they’ll work with natural gas but can also be easily modified to run on 100% hydrogen. According to some industry estimates, these boilers should be available from 2023-2025.
Stage 2
A 20% hydrogen blend will be introduced into the gas supply. Most boilers will be able to use this as normal – including all new Worcester Bosch boilers. The rollout of 20% hydrogen isn’t expected to begin until 2028 at the very earliest.
Stage 3
When the gas supply switches to 100% hydrogen, every new boiler sold in the UK will simply be a hydrogen boiler. This is the ultimate goal, but it probably won’t happen until the mid-2040s.
What is a hydrogen boiler?
A hydrogen boiler is very similar to a natural gas boiler, which is why many people think they’re the best way to decarbonise our homes.
Hydrogen does burn differently to natural gas, so there will be some design changes inside the boiler itself. But the basic principles are the same.
So, although it’s a big change in many ways, it shouldn’t cause too much disruption. High fives all round!
How much will hydrogen boilers cost?
Good news. Hydrogen boilers are still at prototype stage, but manufacturers are saying they shouldn’t cost any more than current Natural Gas boilers.
And because they work in a very similar way, there shouldn’t be any big extra costs when it comes to things like installation and maintenance.
So why the change?
Natural gas is a fossil fuel that produces CO2 when burned. And that makes heating our homes one of the biggest contributors to climate change in the UK.
Hydrogen is very different though. The only by-product of burning hydrogen gas is water – and there are also ways of making hydrogen gas that are very carbon efficient.
Hydrogen is so promising as a low-carbon fuel that the government sees it as an essential way of reaching our goal of being net zero as a country by 2050.
When will the transition to hydrogen happen?
The simple answer is nobody really knows for sure at the moment.
Our best guess is that the introduction of the 20% hydrogen blend will happen within the next decade, but the switch to 100% hydrogen will take significantly longer.
This relatively slow change means most people will have updated to a hydrogen-ready boiler by the time the switch happens, so adapting to the new type of gas should be relatively painless.
Why can’t we go 100% hydrogen faster?
There are a few reasons.
Firstly, converting all the boilers in the UK is a big job, even if the changes needed to each boiler are fairly small.
Secondly, hydrogen boilers are still at prototype stage, so manufacturers aren’t ready to roll them out yet.
And finally, there’s the supply issue – the UK doesn’t currently produce enough hydrogen to power everyone’s boilers.
Solving these challenges will take a bit of time, but a lot of progress has been made already. So we’re confident a cleaner, greener, hydrogen-powered future is just round the corner!
Nearly all gas appliances that are in use today, including our boilers, are able to run on a mixture of hydrogen and natural gas. This is called a blend and sees 20% of the fuel source powering the appliance being hydrogen gas, with the remaining 80% being natural, which is where the term 20% Hydrogen ready comes from.
A hydrogen-ready boiler is a gas-fired heating boiler which is capable of burning either natural gas or pure (100%) hydrogen. Hydrogen-ready boilers are the key to enabling conversion of the existing gas distribution networks from natural gas (which is mostly methane) to hydrogen.
Hydrogen is a carbon-free energy carrier and combustion of hydrogen produces no carbon dioxide at the point of use.
Hydrogen can be manufactured from water using electricity as a renewable energy source, or from natural gas accompanied by carbon capture and storage. Recent work, such as the H21 Leeds City Gate study, has shown that conversion of UK gas distribution networks is feasible and could help to decarbonise the heating of buildings. A hydrogen-ready boiler is intended to provide a like-for-like replacement for an existing natural gas boiler. The boiler can be quickly and easily converted to burn hydrogen at the time when the local network switches over.
Many existing homes, despite energy efficiency improvements, still have relatively poor insulation and high rates of air exchange with the outdoors.
A hydrogen-ready boiler is capable of accommodating an existing high temperature heating system in a hard-to-heat building. Where costs are highly constrained, the boiler (and conversion of the local gas network) provides an accessible way to deeply decarbonise heat.
Heat users have high expectations of system control; to respond quickly to heat demands providing rapid warm-up of the building, or to deliver heat reliably in extreme weather events or times of unexpected building occupancy. Compared to other technologies, boilers offer very resilient and flexible heat delivery, and provide consistent performance in a wide range of operating conditions. From an end-user point of view, a hydrogen-ready boiler does not require any behaviour change and will provide the same delivery of comfort as an existing appliance.
Hydrogen also offers benefits for the energy system as a whole. In order to use a high proportion of renewable energy generation, electricity systems need large quantities of flexible energy storage. Hydrogen offers one of the most attractive means of providing large-scale energy storage. Heat is a very large energy demand which varies rapidly at key points in the day. Currently this demand is satisfied by the distributed energy storage intrinsic to the gas networks; the continual use of a form of gas for heating will relieve stress on future electricity systems, as well as offering overall energy flexibility and resilience. Creating a national hydrogen infrastructure will also open the door to wide-scale use of hydrogen for transport. Hydrogen fuel cells are seen as an attractive technology for commercial and heavy transport applications.
The boiler is very similar to its natural gas predecessors; it is constructed and functions in much the same way as an existing condensing boiler. While some components are distinct, such as the flame detector, most are identical to those used in natural gas boilers today.
Converting a hydrogen-ready boiler from natural gas to hydrogen will take around an hour and involve changing a couple of components such as the burner. It is envisaged that Gas-Safe engineers will be trained to work with hydrogen by a qualification scheme similar to that available today for LPG.
There is no reason why, at similar scale, hydrogen-ready boilers should not reach a similar cost to natural gas boilers today. The ancillary components, accessories and controls will be identical to those for natural gas boilers. The property will at some stage require a hydrogen-ready gas meter to be fitted ready for network conversion, however this could be installed on a later date than the boiler. Initially, hydrogen-ready boilers might form a niche market, but a regulatory change mandating their installation would make them a high volume technology, just as natural gas boilers are today.
See our 39 reviews on Trustpilot