SAF benefits at risk of being ‘diluted’ by Heathrow expansion, government warned

Philip Lange / Shutterstock.com

THE BENEFITS of sustainable aviation fuel (SAF) are at risk of being “diluted” by a third runway at London Heathrow Airport, a campaign group has warned, following government research predicting significant emissions rises caused by expansion. 

The government threw its support behind the longstanding plans to build a third runway at Heathrow last February and hopes for it to be built by 2035. Expansion will increase capacity at Heathrow, already one of the world’s busiest airports, by more than 50% to around 756,000 flights per year. 

However, a report published by the Department for Transport (DfT) last week found that the additional carbon emissions associated with the increased capacity will have “significant adverse environmental effects”. The report, written by consultancy AECOM and commissioned by DfT, said that technology Heathrow hopes will mitigate emissions, including SAF and engineered removals, will "not remove the increase in absolute emissions associated with the higher level of aviation activity”. 

The report added that “there is a high degree of uncertainty associated with future decarbonisation pathways, particularly in relation to aviation”. 

Anna Krajinska, UK director of the European Federation for Transport & Environment (T&E), told TCE: “The climate benefits of SAF risk being diluted by air traffic growth enabled by airport expansion. Without managing absolute demand and capacity, technological developments alone cannot align the sector with necessary emissions reduction trajectories.” Analysis by T&E last year found that European aviation emissions will continue increasing well into the 2040s if projections of air travel and SAF uptake are realised. 

The UK Climate Change Committee has recommended a cap on annual aviation emissions of 37.5m tCO2e by 2050. According to a 2015 assessment by the Airports Commission, the extra capacity at Heathrow will contribute 310m tCO2e of extra emissions over 60 years, amounting to around 5m tCO2e per year, while construction alone will generate 11.3m tCO2e. Flights departing from Heathrow released 17.2m tCO2e in 2024, according to the airport’s latest sustainability report. 

Heathrow is yet to receive the final greenlight for expansion, with approval expected as late as 2029, and the latest analysis is subject to a public consultation running until September. The project could also be placed in doubt following prime minister Sir Keir Starmer’s resignation announcement this week. His most likely successor, Andy Burnham, said in 2018 there was a “strong case” to postpone Heathrow expansion. 

A DfT spokesperson said: “We recognise that people living around Heathrow have legitimate concerns, which is why we are consulting on a framework that would require any future proposal to be compatible with the UK’s climate obligations, not breach legal air quality limits, and ensure noise impacts do not worsen beyond current baseline levels.

“An expanded Heathrow could support over 60,000 jobs and deliver around £40bn in economic benefits across the UK, but any scheme would need to meet these strict requirements before any plan is approved.”