The UK’s largest undeveloped oil field has revealed the full scale of its environmental impact, should it gain approval by the government.
Developers of the Rosebank oil field said nearly 250 million tonnes of planet warming gas would be released from using oil products from the field.
The amount would vary each year, but by comparison the UK’s annual emissions in 2024 were 371 million tonnes.
The field’s developer said its emissions were “not significant” considering the UK’s international climate commitments.
Rosebank is an oil and gas field which lies about 80 miles north-west of Shetland and is one of the largest undeveloped discoveries of fossil fuels in UK waters.
It is said to contain up to 300 million barrels of oil and some gas, and is owned by Norwegian energy giant Equinor and British firm Ithaca Energy.
The field was originally approved in 2023, but in July a court ruled that a more detailed assessment of the field’s environmental impact was required, taking into account the effect on the climate of burning any fossil fuels extracted from it.
A public consultation has now been opened, and will run until 20th November 2025.
The final decision on whether to approve the field will be made by the Energy Secretary.
Until recently such projects were only required to consider the impact on the environment from extracting the fossil fuels.
But in June last year the Supreme Court ruled that authorities must take account of the impact from also using the products, after a woman in Surrey challenged the development of her local gas project.
This ruling was then used in a further challenge to the Rosebank oil field by environmental campaigners Uplift and Greenpeace – which was subsequently successful in January.
Equinor was required to recalculate the “full impact” of the field and it now estimates that it will contribute an additional 249 million tonnes of the planet warming gas CO2 over the next 25 years.
This is more than 50 times greater than the original figure of 4.5 million tonnes it gave from extracting the oil and gas.
The UK has a target to produce no additional emissions by 2050 and Energy Secretary Ed Miliband has been vocal about the need to move away from fossil fuels.
On Tuesday, he told an industry conference that the UK’s dependence on fossil fuels was its “Achilles’ heel” and argued clean power was the only way to reduce bills.
The fossil fuels for the Rosebank field are not guaranteed to be used in the UK but would be sold on the international market.
As such the project is unlikely to have an impact on lowering gas prices. The UK’s independent climate advisors said in 2022 that any more domestic oil and gas extraction would have “at most, a marginal effect on prices”.
But Arne Gurtner, Equinor’s senior vice president for the UK, has previously said that: “If the UK needs Rosebank oil, it will go to the UK through open market mechanisms.”
