Will hydrogen replace gas in UK homes?

You may have heard about hydrogen as a future fuel option for everything from home heating to powering our cars.

But is hydrogen a ‘good’ option when it comes to fuel? Here’s the lowdown…


Why do we need to replace gas?

78% of homes in the UK are currently heated via natural gas. Gas is a fossil fuel, mostly composed of methane, and when burned it creates carbon dioxide - this makes natural gas currently responsible for 19% of global greenhouse gas emissions, with oil accounting for 21% and coal for 25%. 

In the UK, using natural gas for heating generates about a third of our greenhouse gas emissions, so it’s a big part of the puzzle when it comes to meeting our net zero emissions target by 2050.

To help us get there, the government has committed to phasing out new gas boilers from 2025, by installing eco-friendly heating options like air source heat pumps in new build properties - but is hydrogen an alternative to natural gas?

Is hydrogen better for the environment than gas?

Unlike natural gas, burning hydrogen doesn’t release carbon dioxide - it only releases water. This means that it has the potential to be a zero-carbon fuel; however, the process to create hydrogen can still be carbon-intensive. 

Ironically, most hydrogen is currently made from natural gas through a process called ‘steam reforming’. This process uses a lot of energy, and it actually takes more natural gas to produce the hydrogen using this process than would be required if we just kept using natural gas. 

To counter this, the gas industry is advocating for using carbon capture and storage alongside the steam reforming process - this would mean that natural gas is converted to hydrogen, then the carbon dioxide is captured and stored underground, rather than being released into the atmosphere.

Another method of producing hydrogen is via electrolysis, which uses electricity to create hydrogen from water. This method doesn’t produce CO2, but it’s currently very expensive to run on a large scale. 

Electricity already costs over four times the price of gas per kwh, and with the added conversion losses from making the hydrogen, the hydrogen created could be six to eight times as expensive as natural gas - so not a great option for cutting our energy costs.

Could hydrogen replace gas as a home heating fuel?

Hydrogen could, in theory, be supplied to homes across the country in the same way as we currently receive natural gas via the grid, and used to power our boilers. 

According to the Institute of Mechanical Engineers, a hydrogen/natural gas blend could heat homes around the country from 2023, with all five of Britain’s gas grid companies preparing capability to provide the gas.

A study by Keele University found that it’s possible to continue our existing gas cookers, boilers and heating systems by using a maximum of 20% hydrogen, 80% natural gas. However, to be able to use 100% hydrogen, new pipe infrastructure, boilers and cooking appliances would have to be installed - so the switch to a hydrogen grid would be a significant investment.

This would mean that up to a fifth of the natural gas currently used could be replaced by hydrogen, according to the Energy Networks Association (ENA), reducing carbon emissions by the equivalent of 2.5m cars a year, without needing to upgrade household appliances.

However, as the steam reforming method of producing hydrogen uses a lot of natural gas, it’s estimated running our gas grid on hydrogen would require 47% more natural gas than it already does. That’s good news for the gas industry, but means higher heating bills for the rest of us, and more reliance on gas exporters like Russia and Qatar.

What else could hydrogen be used for?

According to a government report, “hydrogen is not a panacea for reaching the Net Zero emissions reductions by 2050 but can grow to become “a big niche” fuel in particular sectors and applications”.

So although hydrogen might not be the best solution for heating our homes, it does have a role to play in decarbonising industrial processes, such as those which can’t be electrified because they require extremely high temperatures.

Hydrogen could also play a role in decarbonising transport, such as areas of the rail network which are hard to electrify, bus networks which have a local pattern of operations susceptible to refuelling at depots, and some parts of shipping and aviation, as well as a means of storing energy.

Is there a better option for heating our homes?

Switching our grid from natural gas to hydrogen will either increase our reliance on natural gas (if hydrogen is made using steam reforming) or vastly increase our energy bills (if the hydrogen is made via electrolysis). 

To free ourselves from fossil fuels, renewable energy is always a more sustainable option - with the ability to remove our reliance on fossil fuel suppliers, reduce our carbon emissions and lower our energy bills. 

Additionally, reducing our energy consumption allows us to not only lower our carbon footprint, but also our household costs. Making our homes more energy efficient, so they don’t need as much energy to heat, as well as being mindful of our energy use, all adds up to much lower energy use. 

Measures like insulation and triple glazed windows help to reduce the energy needed to heat a home, or swapping to renewable energy sources like solar panels and air source heat pumps allow us to detach from the gas grid entirely. 

According to Citu, a typical air-source heat pump will deliver about 3 kWh of heat for every 1 kWh of electricity used to power it - this makes heat pumps six times more efficient than using electrolysis-created hydrogen power. Where 1 kWh of electricity could be used to make 0.5 kWh worth heat by producing hydrogen, it could instead be used to create 3 kWh of heat via an air source heat pump.