Dr Boswell’s application for judicial review was concerned with the Secretary of State’s approach to the greenhouse gas emissions from the gas fired power station with carbon capture and storage that forms part of the NZT project.  Lieven J had dismissed Dr Boswell’s application at first instance ([2024] EWHC 2128), and the appeal against that decision was heard over two days in March 2025.

In a Judgment handed down on 22nd May 2025, the Court of Appeal (Sir Keith Lindblom, SPT, Stuart-Smith LJ and Holgate LJ), rejected all three of Dr Boswell’s grounds of appeal.

Ground 1 relied on an argument that, properly understood, the Secretary of State had reached her conclusions on the significance of NZT’s greenhouse gas emissions applying the approach set out in section 6.3 of the IEMA Guidance.  On that basis, it was said that the Secretary of State’s finding that the impact of these emissions would be significant and adverse carried with it the conclusion that the project was not compatible with the UK’s net zero trajectory, and this was inconsistent with her conclusion that the development would support delivery of net zero.  The Court of Appeal rejected that interpretation of the decision letter, describing it as “wholly artificial” and Dr Boswell’s approach as “a classic example of the misuse of judicial review in order to continue a campaign against a development (and the policy in a [National Policy Statement]) once a party has lost the argument on the planning merits.”

Ground 2 alleged that Lieven J had erred in concluding that the statement made in paragraph 5.2.2 of National Policy Statement (“NPS”) EN-1 that “CO2 emissions are a significant adverse impact from some types of energy infrastructure which cannot be totally avoided (even with full deployment of CCS Technology)” encapsulates the assessment of significance for the purpose of the EIA Regulations 2017 as well as the weight to be given to the assessment of significance as part of the planning balance exercise.  The Court of Appeal described the Appellant’s argument as “misconceived” and concluded that the policy was expressed in sufficiently broad terms to encompass both these matters.

Ground 3 alleged that the Secretary of State could not lawfully endorse the applicant’s use of the IEMA Guidance for the purpose of assessing significance in the ES, while at the same time assessing significance in a different way, and/or gave inadequate reasons for doing so.  This ground was rejected as improperly intruding upon the Secretary of State’s decision-making powers by seeking to insist that (as a matter of law) she was obliged to compare the emissions against a ‘benchmark’ or to use ‘contextualisation’ to assess significance.  The Court of Appeal held that the evaluation of the significance of an estimated amount of greenhouse gas emissions and its acceptability are matters of fact and judgment for the decision-maker.  There is no legal principle requiring the judgement to be reached by reference to a benchmark or by contextualising the emissions.  The conclusions reached by the Secretary of State on this issue were both lawful and properly reasoned.

Hereward Phillpot KC and Isabella Tafur, instructed by Freshfields LLP, appeared on behalf of Net Zero Teesside Power Ltd. and Net Zero North Sea Storage Ltd.

A copy of the Judgment can be found here.