Hydrogen – The green fuel of the future

As the UK begins its journey on the road to decarbonisation, home heating and hot water production has increasingly come under the spotlight. To support the Government’s 2050 net zero target, the heating industry must prepare for the decarbonisation of heat and its impact on heating technologies within the home.

Hydrogen is set to play a key role in the green industrial revolution for the heating industry and Glow-worm is here to support you on this journey, helping you to keep Britain glowing now and into the future.

What is hydrogen and where does it come from?

Hydrogen can be extracted from many substances but most commonly, water which is in plentiful supply, making it the perfect future energy source. The significant advantage of hydrogen is that it’s environmentally friendly and can even be a climate-neutral energy carrier when produced as “green” hydrogen.


Water and oxygen are the only by-products of burning hydrogen.


Hydrogen is capable of lifting a space shuttle and will keep planes in the air for hours, so it is more than capable of heating our homes.

Unlimited Availability

Hydrogen can be obtained from different substances, in particular water which the earth has a plentiful supply of.


It can be a fuel or a coolant, generate electricity and heat. And it has even more potential in the future.

Hydrogen is a substance that does not naturally occur in its pure form, it needs to be produced. This can be achieved using three different production methods, these are green, blue and grey production - depending on the amount of CO2 emissions during the production process.

Green hydrogen is considered the fuel of the future as it is a zero carbon emission process, 100% sustainable and very efficient. Experts calculated that a change from grey to green hydrogen will already save 830 million tonnes of CO2 that are emitted annually. In the UK, green hydrogen is the aim but to begin with, there will be a mix of blue and green hydrogen.

How is hydrogen produced?

Hydrogen molecules in their isolated form are extremely rare but there are several methods to extract hydrogen from water or methane.

Green: Carbon-neutral

  • (1) By passing an electric current through water, we can break it down into oxygen and hydrogen, this process is called electrolysis. If we only use sustainable generated electricity, such as wind or solar PV, the process does not generate any carbon emissions.
  • (2) The hydrogen can then be stored in tanks or even underground caverns and transported via pipelines, tankers or trucks.
  • (3) It can then be used wherever current fossil fuels or other energy sources have been used so far.

Blue: C02 is stored

Blue hydrogen is produced from natural gas. The CO2 that is produced is not released into the atmosphere, but up to 90% of the CO2 can be stored in tanks or underground caverns preventing emissions. Lifecycle carbon emission savings of up to 85% are possible with blue hydrogen when compared to natural gas boilers. (Source: The CCC)

Grey: C02 is released into the atmosphere

Like blue hydrogen, grey hydrogen is produced from natural gas. However, the CO2 is not stored underground in this process, but gets released into the atmosphere and causes emissions.

Hydrogen in buildings

In the UK, the journey to fully decarbonised heating systems is a long-term vision, but in an effort to lower carbon emissions on the way to a 100% hydrogen infrastructure, networks are currently being tested to supply a mixture of up to 20% hydrogen with natural gas. Today, all Glow-worm boilers are currently being tested using 20% hydrogen as it speculated that 20% hydrogen mix could be introduced into the gas grid as early as 2023.

A gas conversion programme must be established to ensure a 100% hydrogen gas infrastructure is achieved.

As part of the government’s 10-point plan, they have set the aim of producing a hydrogen heated neighbourhood by 2023, a village by 2025 and a town by the end of the decade.


How heating with hydrogen works

The main components of traditional gas boilers, which installers have become familiar with, will remain the same but will require some adaption in order to work with hydrogen. Some of the challenges identified with developing a hydrogen boiler which must be considered are; flame detection, flashback prevention, gas-air control, condensate management and materials compatibility.

Hydrogen vs today's boilers

Sizing: The appliances will be comparable in shape, size and weight to the traditional gas boilers of today.

Usage: The appliances will be connected to the same heating distribution system in the property (radiators, floor heating) and will still provide heating and hot water, in one unit or with the support of external DHW storage).

Efficiency: Hydrogen boilers will have similar efficiency levels to today’s boilers.

Want to learn more about hydrogen and the decarbonisation of heat?