Scientists suggest a better alternative to UK’s ‘pipe dream’ of using hydrogen for heating

A new scientific report has refuted the U.K. secretary's claims of calling hydrogen for heating a "silver bullet."

More than 30 independent research papers examining hydrogen and heating were analyzed for the report, published in the scientific journal Joule on Tuesday.

"The evidence assessment shows that the widespread use of hydrogen for heating is not supported by any of the 32 studies identified," noted the review report.

"Compared to other alternatives such as heat pumps, solar thermal, and district heating, hydrogen use for domestic heating is less economical, less efficient, more resource intensive, and associated with larger environmental impacts."

The report was released in response to recent remarks made by the U.K.'s energy secretary in his speech at the House of Commons.

"I think hydrogen is ultimately the silver bullet. We create it from renewable sources... we use it as an effective battery, and it can then, with some adjustments, be piped through to people's houses to heat them during the winter," U.K.'s newly elected energy secretary, Jacob Rees Mogg, said on Friday.

Energy experts may slightly concur with Mogg's view but not entirely.

"Using hydrogen for heating may sound attractive at first glance," Jan Rosenow, the report's author and Europe Director at the energy think-tank the Regulatory Assistance Project told BBC.

"However, all of the independent research on this topic comes to the same conclusion: heating with hydrogen is a lot less efficient and more expensive than alternatives such as heat pumps, district heating, and solar thermal," he said.

Hydrogen for heating homes

Hydrogen is attractive in Europe, particularly after the Russia-Ukraine war, since it can be produced from water, a nearly limitless resource, and because it burns cleanly.

However, there are significant difficulties in producing hydrogen, making it no miracle energy source. The majority of hydrogen produced today uses fossil fuels (also known as grey hydrogen), which is a more environmentally damaging approach than just producing hydrogen from methane gas.

Electricity from renewable sources must be utilized to electrolyze water in order for hydrogen to be regarded as "green." The method's inefficiency is the issue.

Utilizing a heat pump to directly heat a home utilizes less energy than producing electricity from wind or solar, converting it to hydrogen, and then burning the hydrogen at home.

A heat pump can be used to heat and cool a home. The system draws energy from the outside air or, in the case of a geothermal heat pump, from the earth. It then pumps that energy through coils containing refrigerant to produce heat for the house. For cooling, there is a reversing valve. That has significant positive effects on the climate.

"In the U.K., heating homes with green hydrogen would use approximately six times more renewable electricity than heat pumps," David Cebon of the Hydrogen Science Coalition and Professor of Mechanical Engineering at Cambridge University told BBC.

"We do not have the time or resources to waste further investigating hydrogen's role in home heating, especially when the well-known laws of thermodynamics determine the answer," he said.

Despite the considerable attention that hydrogen has received, there is no independent evidence that hydrogen should be used extensively for space and hot water heating.

"None of them [Studies] provides evidence that would support the case for widespread use of hydrogen for heating, although some identify complementary roles of hydrogen, particularly in district heating and hybrid heating systems." noted the report.

"Policymakers are therefore well advised to consider the existing research carefully before allocating significant public funds for hydrogen heating," the report concluded.