CCC says Heathrow expansion requires tougher aviation emissions measures
The Climate Change Committee (CCC) has warned that there is currently no credible policy pathway for expanding Heathrow while meeting the UK’s climate targets, arguing that any expansion should be accompanied by measures requiring the aviation industry to address its full emissions.
image: Heathrow Airport
The advice, published in response to a request from the Department for Transport (DfT), examines the proposed changes to the Heathrow Expansion National Policy Statement and the wider role of aviation in meeting the UK’s carbon budgets. The CCC says Heathrow expansion could be compatible with the UK’s climate commitments, but only if government introduces policies that ensure aviation fully addresses its emissions by 2050.
The committee recommends legislation requiring the aviation industry to address residual emissions either through direct emissions reductions or by paying for engineered carbon removals. It also calls for a long-term strategy for aviation emissions, including contingency measures if progress towards the sector’s climate objectives falls behind.
The CCC’s assessment reflects wider concerns about the pace of aviation decarbonisation. Its 2026 progress report found that aviation emissions fell by 0.5% in 2025 to 37.9MtCO₂e, despite a 3% increase in passenger-kilometres. It said it was too early to establish whether aviation emissions would grow, plateau or decline in the longer term.
Sustainable aviation fuel (SAF) is identified as one of the main measures available to reduce aviation emissions. The CCC reported that SAF accounted for 2.5% of UK jet fuel supply in 2025, with the government’s mandate requiring this to rise to 3.6% in 2026 and 10% by 2030. The committee also identifies improved aircraft efficiency, carbon pricing and engineered removals as components of the pathway to net zero aviation.
The CCC’s analysis suggests that requiring aviation to bear the full cost of addressing its emissions would have implications for the cost of flying. It estimates that, by 2050, the additional cost could be equivalent to around £150 on a return flight to Alicante and £400 on a return flight to New York, depending on the measures adopted and how costs are passed through to passengers.
The committee also estimates that Heathrow expansion would account for around 6.9% of remaining UK carbon emissions in 2050 under its analysis. It says Heathrow currently accounts for around half of UK aviation emissions, although the precise impact of expansion depends on how aviation demand, aircraft efficiency and decarbonisation develop.
The government backs the development of a third runway at Heathrow and is reviewing the Airports National Policy Statement as part of establishing the planning framework for expansion.
The DfT said it would consider the CCC’s advice alongside responses to its consultation on the Heathrow Expansion National Policy Statement, adding that any expansion proposal would need to align with the government’s net-zero targets.
CCC’s chief analyst Dr James Richardson is speaking at AIR on 30 September. His keynote is followed by a high-level panel on aviation decarbonisation in which the panel will explore whether it’s time for a more candid discussion about priorities, trade-offs and where investment can deliver the greatest impact.
AIR, running 29/30 September at ExCel London, is free to attend. Register now: