Looming EV policy U-turn could result in more than half of Rosebank’s emissions

Proposals being considered in a Government consultation on watering down the Zero Emission Vehicle Mandate policy could see the UK’s carbon emissions pushed up by millions of tonnes.

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By Jess Ralston

info@eciu.net

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Even the least severe cut to EV sales targets proposed (from 80% to 70% of new cars in 2030), together with previous watering down of the policy by Government, would lead to emissions greater than burning all the gas in the Jackdaw field [1].

If the Government cut the target even further to 50%, this would likely lead to a policy ‘cliff edge’ in 2035, and could mean an additional 147 MtCO2e (megatonnes of carbon), more than half (58%) of the emissions from the use of the oil in the Rosebank field [2]. 

Jess Ralston, Head of Energy, at the Energy and Climate Intelligence Unit, said: 

“The vast majority of oil – 80% [3] - from drilling in the North Sea immediately ships overseas. Even at the less severe end of what the Government is considering, the resulting extra emissions are more than burning all the gas in the Jackdaw field and in a worst-case scenario are similar to an oil field. With climate concern high among the public after the extreme heat and persisting drought, and public support for the net zero target up above two-thirds, a decision to U-turn could look very odd. [3] 

“With diesel prices through the £2 a litre mark, the second-hand EV market booming and ministers having talked about getting families off the fossil fuel rollercoaster, this would be the opposite, locking in higher driving costs, more air pollution and higher carbon emissions. 

“In echoes of ‘dieselgate’, the Government’s watering down of policy last year has already incentivised manufacturers to sell more hybrids which burn far more fuel, so produce more pollution and cost families much more to drive than claimed. 

“While EV sales are rocketing in Europe, UK-based car manufacturers have sadly been slow to embrace the shift, falling behind rivals. But the Government could find ways to support them transition, securing jobs for the long-term, that doesn’t involve pushing up driving bills and emissions as we head into a diesel crisis and likely the hottest year on record.” 

Changes to the ZEV Mandate could incentivise manufacturers to try to sell more plug-in hybrids which have been found to consume five times more fuel than their manufacturers claim [5]. 

Previous analysis from ECIU [6] has found that the watering down of the ZEV mandate would add billions to the nation’s driving bill as electric cars are on average hundreds of pounds a year cheaper to run. 

Despite claims to the contrary, the car industry as a whole has met the ZEV Mandate targets for the first two years of the policy and is on track to meet them this year too [7]. 

France saw EVs achieve a 42% new car sale market share in September with Germany reaching 34.6% in the same month [8] 

Notes to Editors 

 

  1. 47 MtCO2e. The gas that would be extracted from the Jackdaw field would be responsible for 35.8 MtCO2e https://assets.publishing.service.gov.uk/media/69203f99cf3db184075cfd90/Further_Information_Part_1_-_Scope_3_Emissions_Assessment.pdf 
  2. The oil that would be extracted from the Rosebank field would be responsible for 254 MtCO2e https://assets.publishing.service.gov.uk/media/68ef61fd82670806f9d5e0a9/Rosebank_Reg_12__1__Assessment_of_Scope_3_Emissions__OPRED_131025__errors_corrected.pdf  
  3. https://www.carbonbrief.org/analysis-why-clean-energy-will-cut-uk-gas-imports-by-more-than-north-sea-drilling 
  4. https://climatebarometer.org/climate-barometer-trackers/?showgraph=15663499  
  5. https://www.transportenvironment.org/articles/plug-in-hybrids-now-emit-five-times-on-average-what-official-tests-claim-eu-data 
  6. https://eciu.net/media/press-releases/government-slowing-uks-ev-sales-would-cost-british-drivers-billions-analysis 
  7. https://eciu.net/media/press-releases/car-industry-on-course-to-meet-ev-sales-targets-in-2025-analysis 
  8. https://www.reuters.com/business/europe-ev-sales-rose-70-september-almost-30-market-share-2026-10-19/  

 

Methodology 

Total new car sales were assumed to be 2million per year, based on recent averages.  Market share of EVs was calculated for scenarios with progressively weaker versions of the ZEV Mandate (including options in ZEV Mandate Review (DfT, Aug 2026)), and assumptions about the extent to which flexibilities might be used.  These ‘missed EV sales’ were split between petrol ICE and petrol PHEV (on the assumption that diesel continues to fade out) using a simple linear trend from their current split through to the year in which new ICE sales are 0%.  The number of each type of car sold during the ZEV Mandate and operating at the mid-point of each year out to 2050 was calculated, accounting for scrappage after the typical lifespan of 14years. 
  
ICE petrol consumption per mile was estimated based on analysis of recent years’ data for UK-wide data: petrol fossil fuel usage by cars from ECUK Table C8 (DESNZ, Apr-2026); biofuel percentage by mass deduced from ET 3.5 (DENSZ, 2026), converted to percentage by volume using factors for mineral petrol and bioethanol from GHG Conversion Factors 2025 (DESNZ, 2025), and then added to fossil fuel petrol as a volume.  Future energy consumption per mile was based on this current value, but modified for biofuel content according to RTFO targets (DfT, 2025) and forecast improvements in vehicle efficiency from Transport Analysis Guidance (TAG) Table A.1.3.10 (DfT, 2026). EV energy consumption per mile was estimated based on research into real-world consumption (e.g. EV Database, accessed Apr-2025) for popular models sold in recent years, scaled by charger efficiency of c.90%.  Future values used forecast improvements from Transport Analysis Guidance (TAG) Table A.1.3.10 (DfT, 2026). This was then converted into gas demand for power plants using gird losses (ET 5.2 (DESNZ, 2026)), gas power generation share (ET 5.1 (DESNZ, 2026)), and gas power plant efficiencies (ET 5.1 (DESNZ, 2026)), with future scenarios drawing on the Balanced Pathway in the Seventh Carbon Budget (CCC, 2025).  PHEV energy use was modelled based on analysis of data from Real World Emissions (EU Commission, accessed Aug 2026) and using the actual utility factor (UF), such that a PHEV was assumed to use c.25% as much electricity as an EV (based on current charging behaviours) and c.85% as much fuel as an ICE (the apparent ‘excess’ being because a PHEV is heavier than an equivalent ICE). 

Annual mileage of 8,000 miles was used, on the basis that this used to be the typical value from Table NTS0901a (DfT, accessed Apr-2026), and is often still used in analysis by various organisations.

Greenhouse gas emissions from fossil fuel consumption were calculated using standard emissions factors from GHG Conversion Factors 2025 (DESNZ, 2025).