Norway's Equinor and Scotland-based SSE Thermal have set their sights on jointly developing two low-carbon power stations in the UK’s Humber region that they claim would be among the first in the world to utilise carbon capture and storage (CCS) and hydrogen technologies.

The plans to build one 900MW gas-fired power station with CCS and a flexible 1.8GW hydrogen power station would support the UK’s transition to net-zero carbon emissions and accelerate the decarbonisation of northeast England's Humber region, the UK’s largest and most carbon-intensive industrial cluster, Equinor said last week.

"Our base case is the use of blue hydrogen [at the 1.8GW plant], but we will study different opportunities, also green hydrogen. It is still early," an Equinor spokesman told Recharge's sister publication, Upstream.

Blue hydrogen is produced from natural gas with CCS, which begs the question why Equinor would go to the trouble to produce hydrogen in such a way and then burn it at a power plant, rather than just burn natural gas with CCS. After all, the latter would be a much more energy efficient and therefore cheaper option. Every tonne of hydrogen produced via steam methane reformation requires about two tonnes of natural gas, plus several megawatt hours of heat energy. And natural gas contains more than three times as much energy per cubic metre than hydrogen.

"The reason we want to build different power plants with different technologies is that we want to test different low-carbon solutions for power production," the spokesman explained.

CCS technology is not capable of capturing all the carbon emissions from a particular source, which is why both plants would be classed as "low-carbon". Equinor claimed that the hydrogen plant would produce "zero emissions at the point of combustion", but burning H2 in air results in the formation of nitrous oxide, which is 300 times more powerful a greenhouse gas than carbon dioxide. Most of this nitrous oxide can, however, be captured by techniques such as injecting ammonia vapour into the flue gas stream, but a small proportion will still reach the atmosphere.

Methane, the predominant molecule in natural gas, is also a powerful greenhouse gas, so any leakages from the supply chain would also contribute to climate change.

The 900MW Keadby 3 gas plant "would have the potential to come online by 2027" and the 1.8GW Keadby Hydrogen projects "could come online before the end of the decade... with appropriate policy mechanisms in place".

The latter would be the world's first major 100% hydrogen-fired power station, according to Equinor and SSE.

“Final investment decisions will depend on the progress of policy frameworks that are commensurate with the delivery of this critical net zero enabling infrastructure,” said Equinor.

Offshore CO2 infrastructure is being developed by the Northern Endurance Partnership, a six-member group that includes Equinor.

According to Equinor, a formal consultation for Keadby 3 concluded early this year and the project is currently progressing towards the submission of a development consent application this spring.

Grete Tveit, senior vice-president for low carbon solutions at Equinor, said: "These world-leading power plants at Keadby will accelerate efforts across the Humber to create a decarbonised industrial cluster."

The projects are a further step in Equinor’s ambitions for the Humber, she added, following on from its H2H Saltend project that will start producing low-carbon hydrogen at scale by the mid-2020s.

“We believe these technologies are vital for heavy industry, flexible power and other hard-to-abate sectors to achieve net zero emissions, while also ensuring a just transition for industrial communities,” said Tveit.

Stephen Wheeler, managing director of SSE Thermal, added: “These projects would play a major role in decarbonising the UK’s flexible generation capacity, while supporting a green economic recovery in the Humber."

"With over 12 million tonnes of annual carbon emissions, ideal transport and storage options, and major energy and industrial companies working together, the Humber has to be at the centre of the UK’s decarbonisation strategy.”

The two companies also intend to collaborate on projects elsewhere in the UK.

UK Secretary of State for Business, Energy & Industrial Strategy Kwasi Kwarteng said: “The Humber region is at the heart of our commitment to tackle climate change and is already on the frontline of developing vital clean technologies which will change the way people’s homes and businesses are powered while slashing emissions.

"This new partnership will ensure that world-first technology is being developed in Scunthorpe and across the Humber, creating green jobs and bringing new investment, which will benefit local communities and businesses — revitalising this industrial heartland as the UK builds back greener."

A version of this article first appeared in our sister publication, Upstream.