Gas vs hydrogen boilers is a head-to-head that we’re going to hear more about over the coming years.
Gas boilers have proven to be an effective and reliable way of heating homes but it’s a fossil fuel that releases carbon into the atmosphere. Hydrogen is a low-carbon alternative that could potentially be delivered to homes through the very same gas network.
So, could we soon be installing hydrogen boilers to our homes?
Note: Hydrogen boilers aren’t yet available to buy and at this point in time there’s no guarantee that they will replace gas boilers.
What’s the difference between gas and hydrogen boilers?
Natural gas and hydrogen boilers work in very much the same way. They both burn a gas to produce central heating and domestic hot water. The only real difference is that natural gas boilers release carbon into the atmosphere while hydrogen boilers do not.
Many of the components are the same with a few small differences. These include the burner and flame detector which have to be specifically designed to suit the fuel.
As the internal components are largely the same, a hydrogen boiler can actually work on a supply of 100% natural gas. Likewise, gas boilers can continue to heat a home on a hydrogen blend of 80% natural gas and 20% hydrogen.
It’s been proposed that all boilers installed from 2025 should be hydrogen-ready. This would mean that they could continue heating the home using natural gas but continue to do so should the gas network switch to 100% hydrogen after a short visit from a Gas Safe registered heating engineer.
Gas vs Hydrogen Boilers: Advantages
Gas boilers are a familiar heating system installed right across the UK and that’s because they offer homeowners many advantages.
Relatively inexpensive fuel
Natural gas has always been an affordable source of fuel. One of the reasons why it’s a popular choice for home heating. The price you pay for gas will vary depending on your location and supplier but the average cost sits at around 4.8 pence per kilowatt-hour (p/kWh).
Modern condensing boilers are highly efficient
While they do release carbon into the atmosphere, modern gas boilers are much more efficient than previous models.
Old inefficient gas boilers may have only operated at efficiencies of around 60-70% efficient. Modern boilers, on the other hand, achieve efficiencies of over 90%.
These efficiency ratings relate to how much fuel the boiler is able to convert into usable heat. The remaining heat is lost through the waste gases emitted out through the flue.
Often the simplest heating system to install
If your property is connected to the gas network then a gas boiler is often the most straight-foward and cost effective heating system to have installed.
With a gas boiler there’s also no need to store the fuel as gas is supplied to the property as and when heating and hot water is needed – the same would go for hydrogen too. This is unlike the alternatives such as oil and LPG which need to be stored onsite.
Benefits of hydrogen
Talk of hydrogen replacing natural gas in the gas network is accelerating and this is because of its many benefits.
No carbon emissions when burnt
When burned within a boiler, hydrogen releases no carbon whatsoever. All that’s produced is heat and water vapour. This means replacing the gas being used in millions of boilers across the country with hydrogen would massively reduce the carbon emitted into the atmosphere as a result of home heating.
More efficient than natural gas
Hydrogen contains far more energy than natural gas as around 1kg of hydrogen holds the same amount of energy as 2.8kg of gasoline. This means that less fuel would be needed to provide the same level of heating.
Can be delivered through the existing gas network
The national gas network delivers natural gas to millions of properties across the UK. Finding a low-carbon alternative to natural gas that can still make use of this extensive pipe network would limit costs while also helping to get us closer to achieving carbon targets. And hydrogen fits that criteria.
Other than replacing existing gas boilers with hydrogen-ready alternatives, the infrastructure could potentially remain largely the same.
Could be used for transport
A nationwide hydrogen infrastructure could open the door for hydrogen to fuel various modes of transport at some point in the future. This would help to reduce carbon emissions from transport as well as home heating.
Gas vs Hydrogen boilers: Considerations
Naturally, there are some considerations to be made before a transition to hydrogen could be made. However, it’s worth noting that natural gas isn’t the perfect fuel for home heating. These are a few downsides to gas heating systems.
Safety
If a fault should develop within a gas boiler and go unrepaired then this could lead to a carbon monoxide leak. Carbon monoxide is an odourless, colourless and tasteless gas that if breathed in could have lethal consequences. For this reason, a carbon monoxide alarm must be fitted close to the boiler to detect a leak.
Not kind on the environment
Every time your gas boiler is working to heat your home, carbon is being released into the atmosphere. And increased amounts of carbon in our atmosphere is a leading cause of climate change. To combat climate change and reach carbon targets the way many of us heat our homes will simply have to change.
Gas prices on the rise
Natural gas is subject to import price fluctuations which is seeing the price of gas rise by around 10% each year. This is because natural gas is a fossil fuel and there’s only a limited supply which will eventually run dry.
Hydrogen boiler considerations
While hydrogen could be a bright spot in the low-carbon future of home heating there are a few important considerations that need to be made before it can be added to the gas network.
Production is expensive and can be carbon intensive
Unlike natural gas, to meet demand hydrogen would have to be made. And there are 2 ways of manufacturing it: electrolysis and Steam Methane Reforming (SMR).
Electrolysis is the process of splitting water into oxygen and hydrogen using electricity. As electrolysis requires electricity, this can be a very expensive process. Plus, electricity is considered carbon intensive as its production still involves the burning of fossil fuels in many cases. However, renewable energy generation is on the rise.
STR, on the other hand, involves separating methane into carbon and hydrogen. This is the most commonly used way of producing hydrogen but it creates carbon – a leading cause of climate change. So, for STR to be worthwhile, it’s important to prevent the carbon from being emitted into the atmosphere through Carbon Capture Storage (CCS).
More flammable than natural gas
Hydrogen is far more flammable than natural gas. So, for it to be used to heat domestic properties, a solution to this major concern must be found.
Water vapour
Burning hydrogen produces around 60% more water vapour than burning natural gas. This increased amount of moisture within the boiler isn’t good news for the electrical components. Tackling this potential issue is a concern that hydrogen boiler manufacturers will have to solve.
Hydrogen-ready gas meters
Gas meters are designed to measure the amount of natural gas being used by a property. Should the switch to hydrogen be made then hydrogen-ready meters would need to replace them. It’s thought that the meter could be fitted on a later date than when the hydrogen-ready boiler is installed.
Can gas boilers run on hydrogen?
Conventional gas boilers are designed to burn natural gas however they can still heat the home on a hydrogen blend. This blend would be 80% gas and 20% hydrogen. Beyond this point a hydrogen-ready boiler would be needed.
Can I buy a hydrogen boiler?
Hydrogen boilers aren’t yet available to buy but strides are being made in developing the technology. Leading boiler manufacturers Worcester Bosch and Baxi have both unveiled hydrogen-ready boilers and are pushing for all gas boilers installed from 2025 to be suitable for hydrogen.
It’s not yet clear how much a hydrogen boiler might cost. Given they share many of the same components as gas boilers and are installed in the same way, they should be of a similar price.
Gas vs Hydrogen boilers: Which should be heating our homes?
The gas boiler is a tried and trusted way of heating our homes. However, with efforts to reduce carbon emissions really ramping up, there’s no way we can go on heating our homes in this way for much longer.
Already, it’s been announced that from 2025 new-builds won’t have gas boilers (what will replace them is yet to be decided). And it’s only a matter of time before steps are made to deal with the gas boilers already installed across the UK.
Low-carbon renewable heating systems are one alternative to gas boilers. They don’t release carbon into the atmosphere and can even reduce heating bills. However, they aren’t always practical to install and it would be an incredibly expensive project.
This is why hydrogen is being touted as the most likely natural gas replacement. We will be able to continue heating our homes using the same infrastructure all while reducing carbon emissions.
There isn’t yet a clear path to lowering carbon emissions from home heating. Hydrogen is being considered and as Worcester Bosch and Baxi have proven, the technology exists.
For now, we will have to see how the future plans for home heating progress.
Make your home more efficient today
Hydrogen boilers aren’t yet available to buy but that doesn’t mean that you have to wait to improve the efficiency of your home.
If your existing boiler was installed more than 8 years ago then it’s a good idea to consider a replacement. Over time, boilers lose their efficiency which means that they convert less fuel into usable energy and will cause your heating bills to go up. Modern condensing boilers, on the other hand, are highly efficient which will help to lower your carbon footprint, reduce your heating bills and make your heating system more reliable.
In addition to a new boiler, you should also consider improving your property’s insulation, investing in a smart thermostat and switching energy supplier. All of which can make your home more efficient.
Alternatively, you could move away from a boiler altogether. Renewable heating systems are a low-carbon alternative to gas boilers that heat the home using sustainable fuel sources. Popular options include air source heat pumps, ground source heat pumps and solar thermal panels.
Want to make your home more efficient? Then visit Boiler Guide to get free quotes for a new central heating system from heating engineers in your area. Simply provide a few details about the work you need completing and up to 3 professionals will be in touch to provide a no-obligation quote.
