Regulator to assess claims made about hydrogen home heating trial

29 January 2026

The UK’s competition watchdog has been asked to investigate claims of greenwashing linked to a hydrogen home heating trial in Fife.

Environmental law group Opportunity Green has filed a complaint with the Competition and Markets Authority (CMA), alleging that Scotland Gas Networks (SGN) may have misled households over the environmental impact and cost of the planned hydrogen heat trial.

SGN aims to convert around 300 homes in 2026 from natural gas to hydrogen as part of its H100 Fife project. But the complaint suggests the company’s marketing material could breach the CMA’s Green Claims Code, particularly in how it describes hydrogen as “clean burning” and “zero-carbon”.

Opportunity Green argues such phrases paint an overly positive picture of the fuel, without clearly distinguishing between the different ways hydrogen is produced. While “green hydrogen” can be made using renewable electricity, the group notes it remains energy-intensive and difficult to scale. Other types, produced from fossil gas, result in far higher emissions.

The NGO warns that presenting all hydrogen as equally green risks confusing consumers and overstating its role in cutting emissions. It also questions claims that hydrogen heating could decarbonise homes, highlighting evidence that electric heat pumps are significantly more efficient and could deliver lower bills.

The UK Climate Change Committee has previously said there is “no role” for hydrogen in home heating, warning that doing so could delay emissions reductions.

Further concerns have been raised over nitrogen oxide emissions from hydrogen boilers, with Opportunity Green claiming the supporting evidence remains unclear.

Dominika Leitane, legal officer at Opportunity Green says:

“SGN is using the environmental profile of green hydrogen alongside cost and scalability claims that relate to other types of hydrogen in its promotional materials for the Fife hydrogen heating trial. We believe this pick and mix approach is inaccurate and risks misleading consumers into making decisions that are significantly worse for the environment than portrayed by SGN, such as joining the Fife trial or retaining gas boilers instead of switching to clean, efficient electric heat pumps.

“Whilst green hydrogen is a clean fuel, it’s expensive to produce and uses five times as much electricity to heat a home than a heat pump. With a limited supply of green hydrogen available, this should be reserved for sectors where there are few alternatives, like fertilisers, steel, aviation and shipping.”

SGN has so far not commented on the complaint. The CMA will now decide whether to open a formal investigation.