Excess renewable energy that cannot be absorbed by the electricity grid should be utilised to produce green hydrogen for domestic uses, including household heating, Scotland’s energy minister told the Investing in Green Hydrogen conference in London yesterday.

Gillian Martin pointed to the 28GW of offshore wind due to come on line in Scottish waters in the coming years, saying “we probably will not have access to the electricity grid for all of that” because of the slow grid-connection process, which is carried out by the National Grid Electricity System Operator, a UK-wide body.

“On one hand, you could look at that as a problem, but on the other hand, you can look at it as an opportunity to make hydrogen and deliver it locally.”

Martin told the conference that she advocated the use of green hydrogen for heating, calling upon the UK government to speed up its decision on whether to allow the use of H2 in homes, which is not due to be taken until 2026.

“We don’t have the levers in Scottish government to do everything we want to do in energy,” Martin said, pointing to the fact that the UK government in London still has control over electricity policy in Scotland under its so-called “reserved powers”.

Gillian Martin pictured in her constituency of Aberdeenshire. Photo: Gillian Martin MSP website

A recent report by Scotland’s Net Zero, Energy and Transport Committee, published after a public consultation, strongly criticised the UK's slow grid-connection process, limiting the amount of renewables able to actually feed power into the grid.

The committee could only call for the Scottish government to lobby the UK government and London-based energy regulator Ofgem on its recommendations, such as reform of the current “first come, first served” model of grid connections.

The use of green hydrogen for heating is extremely controversial, with critics arguing that five to six times more renewable electricity would be needed to produce the same amount of heat as electric heat pumps, and therefore be far more expensive to run; that H2 — an indirect greenhouse gas — will leak out of a natural-gas network not designed to transport the far smaller molecule; and that the volumes of hydrogen (and renewable energy) required would make it all but impossible to be anything more than a niche technology.

Indeed, in a recent written response to a Scottish Parliamentary question, Martin — who previously worked in the oil & gas industry — wrote that “hydrogen will potentially play a role in heating some homes and buildings” [our italics].

Current policy — under Scotland’s devolved powers over the environment — is for all new Scottish homes to be built with heating systems that produce “zero direct [greenhouse gas] emissions from point of use” from 2024, which effectively rules out the idea of blending hydrogen into the natural-gas grid.

Scotland will also be the location of the H100 Fife project, the first hydrogen heating trial in the UK, which is due to deliver H2 to 300 households from next year.

Two weeks ago, Martin accompanied the local gas grid operator SGN’s CEO, Mark Wild, to the trial site in Fife, describing her visit as “incredible”.

Hydrogen Insight has reached out to the office of Gillian Martin for further comment on whether hydrogen in heating is the best use case for the limited volumes that will initially be produced by excess offshore wind, given its inefficiency compared to direct electrification and existing demand from industry.

This article was published first by Hydrogen Insight