A gas network has been criticised for failing to explain the risks associated with a landmark trial of hydrogen heating, which could be approved within weeks.
Experts have raised concerns over plans to install hydrogen detectors in homes in Redcar, North Yorkshire, as they said there has not been enough information provided to potential participants.
Northern Gas Networks (NGN) is under scrutiny over safety measures relating to its plans to supply 2,000 homes with hydrogen instead of natural gas for heating and booking.
The first-of-its-kind experiment is seen as the last chance to prove whether hydrogen heating can work in the UK after ministers cancelled a similar trial proposed in Whitby, Ellesmere Port.
Ministers have said they will only press ahead if there is community backing for the Redcar scheme, with a decision expected by the end of the year.
However, a row has broken out over safety, as experts and residents clashed with NGN over the changes needed to people’s homes.
Early safety assessments for hydrogen heating recommended that homes should have holes drilled in their walls to prevent the gas from leaking and igniting.
NGN now says these are unnecessary and that high-tech sensors can be used instead to detect any leaks – but has yet to set out detailed proposals.
Michael Liebreich, an independent energy analyst, said the lack of information was “outrageous” and urged the company to “treat people like adults”.
He said: “People have not been given the information they need about what is actually going to happen to their houses.
“They were never properly told about the original safety case for the trial and are now being asked to consent without a new safety case having been published.”
Hydrogen is more prone to leaks than natural gas and easier to ignite, meaning homes that are taking part in the Redcar trial will have to be modified. Those who do not want to take part will receive an electrically powered heat pump.
In a previous recommendation to ministers, the Health and Safety Executive (HSE) set out measures which it said would bring the risks posed by hydrogen down to a level comparable with natural gas.
These included installing excess flow valves and outdoor metres at homes, as well as the use of odorant to make hydrogen smell like natural gas.
The HSE also said 4x4 inch, permanently open vents should be installed.
It followed a safety assessment which found hydrogen in homes could cause 65 injuries or fatalities per year.
However, NGN has since told Redcar residents they will not need vents and dismissed fears about explosions as “misinformation”.
Instead, the company wants to install hydrogen detectors that will sound the alarm if too much of the gas is detected indoors.
In an open letter, Mark Horsley, chief executive of NGN, said: “There is absolutely no scenario in which we would ever install a product in anyone’s home or community that compromised their safety.”
Mr Liebreich said that although the risk of hydrogen explosions remained “incredibly low”, relying on sensors was an “inherently less safe system”.
Hydrogen gas is far easier to ignite than methane and could easily be sparked by turning on a light switch, lighting a cigarette or a burning candle, said Tom Baxter, an energy consultant and fellow at the Institution of Chemical Engineers.
Mr Baxter added: “I am very concerned. Everything has a failure frequency and you try to get it down to something that is acceptable – but I do not think we can do that with hydrogen.”
An NGN spokesperson said: “As a responsible gas network, safety is always our number one priority and we have decades of experience safely and reliably delivering gas.
“The project will not go ahead without the UK’s independent safety regulator, the HSE, being satisfied.”
The company has agreed to hold a meeting for Redcar residents next month to discuss any concerns, featuring company representatives, a spokesman for the Government and an independent chair.
An HSE spokesman said: “No community trials will take place until all necessary safety assessments have been successfully carried out.”