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”.
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.
Martin told Hydrogen Insight on Friday: “While there will be a limited role for hydrogen in the progress we need to make over the next few years on changing the way we heat our buildings, that may however change over the longer term and we want to support it wherever it makes sense.
“Significant investment in our grid infrastructure is required to ensure clean, low cost renewable electricity can flow to where it is needed. Such infrastructure must be delivered with lasting benefits for our economy and for the people of Scotland.
“While policy and regulation relating to electricity networks is reserved to the UK Government, we must work together to enable a net zero power system which will drive down costs and increase benefits for customers, businesses, workers and communities.”
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”.
She told Hydrogen Insight: “The H100 Fife project will help us understand what role hydrogen might play in decarbonising heat by delivering a 100% hydrogen heat network supplying around 300 domestic properties with heating from green hydrogen.”
Hydrogen Insight had asked Martin 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. But she declined to respond directly to that question.
This article was updated on Friday 15 September to include quotes from Gillian Martin.