Model: North Sea fields could store hydrogen for over seven years of UK demand

On a still winter week, Britain's gas power plants fire up when wind and solar cannot meet demand. On a very windy day, some turbines are switched off because the grid has nowhere to put their electricity. Researchers now point to the empty oil and gas fields beneath the North Sea as a possible buffer: fill them with green hydrogen when renewable power is abundant, then turn that hydrogen back into electricity when the wind drops.

A study published in Applied Energy estimates that suitable depleted fields could provide 3,659 terawatt-hours of hydrogen storage. That is equivalent to more than seven years of projected UK electricity demand in 2040. Green hydrogen is made by using renewable electricity to split water into hydrogen and oxygen; the gas can later be used to generate electricity without the carbon dioxide released by conventional gas.

The researchers assessed North Sea fields according to their geology, including the quality of the impermeable rock layer that keeps gas underground and the amount of hydrogen that might seep away. Working with Ph.D. researchers Zongtai Zhang and Joseph Brown, they built a digital twin of Britain's future electricity system and geological storage, modeling real weather and supply and demand in half-hour intervals rather than relying on annual averages.

The modeled results expose the practical value of scale. With more renewables but no additional hydrogen storage, the grid still relied on gas during windless winter weeks. In a low-storage scenario using only planned sites, hydrogen stores filled quickly, leaving no room to absorb more summer surplus. Only the high-storage scenario, which added depleted North Sea fields, removed the need for conventional gas power plants by 2040; across all scenarios, gas fell to 1% of generation by 2030.

And then? For households, the direct benefit could be a larger reserve of energy during the winter, when demand is highest and renewable output can be low. For fertilizer, steel, cement and glass producers, hydrogen could also provide the intense heat that is difficult to supply with electricity. Because production and storage could sit near offshore-wind connections and existing oil and gas infrastructure, the researchers say coastal communities could draw on related skills and jobs. Those benefits remain conditional: the figures come from a model, and the proposed North Sea storage capacity has not yet become an operating system.