UK Climate Adviser’s Plan Clears Path for Heathrow Growth

(Bloomberg) -- The UK’s climate watchdog has released new recommendations for the government’s decarbonization strategy that include higher projections for airline passenger numbers, helping smooth the way for plans to expand London’s Heathrow Airport. 

The Climate Change Committee (CCC), the independent body that advises the British government, said it’s more optimistic than it previously was about future supplies of sustainable aviation fuel (SAF), an alternative to kerosene made from biofuels or waste. The technology is seen as the only viable solution to reduce airline emissions while still allowing growth. 

The committee is being “less policy prescriptive on airport capacity, because there isn’t an easy relationship between capacity and passengers,” said Piers Forster, the CCC’s interim chair, in a briefing. He added that the government may need to introduce policies to restrict demand if the industry is not adopting alternative technologies fast enough.

The UK is one of the few countries still forging ahead with ambitious climate goals. Yet Prime Minister Keir Starmer’s center-left Labour government is also keen to spur economic growth and is backing plans to add a third runway at Heathrow. The expansion would increase capacity by about 40 million passengers, according to estimates from the airport.

“This government believes in airport expansion,” Transport Secretary Heidi Alexander said at an industry dinner on Tuesday night. A decision on expanding Gatwick, the country’s second busiest airport located in south London, is expected this week. The minister is set to approve the plan, Bloomberg previously reported. 

“Some might say the current national debate about airport expansion highlights a fundamental tension between growing the economy, whilst protecting the environment,” Alexander said. “I say we must do both. I am not some sort of flight-shaming eco-warrior.”

The UK is also set to allow an increase in the capacity at Luton Airport, Bloomberg reported last month.

Climate advocates have raised concerns that a jump in air traffic will imperil the country’s drive toward net zero emissions by mid-century, as technology like SAF and carbon capture have yet to be proven at scale.

The CCC said it has upgraded its expectations for the proportion of SAF likely to be used by 2050, from 25% in its 2020 report to 38% in this year’s projections, in part because of a new government mandate that could give the market a jolt. The UK now requires SAF to make up 2% of jet fuel from flights taking off from British airports. 

The committee’s net zero pathway also allows for a 28% rise in aviation demand to about 402 million passengers by 2050 — 10% more than when it last released the advice 5 years ago. Projections by the previous Conservative-led UK government suggested that passenger numbers would grow by 70% by 2050, assuming that airports would expand. 

The committee said it expects passenger growth to be naturally constrained by higher ticket prices because of carbon pricing and investments in SAF and carbon capture. The analysis assumes the industry is “responsible for cleaning up its own mess,” Emily Nurse, head of net zero at the CCC, said in the committee’s briefing. 

Ed Miliband, the UK’s energy secretary, said last month that the expansion would not go ahead if it did not fit with the country’s carbon goals. Emma Pinchbeck, the CCC chief executive, said it had not looked specifically at airport expansion or Heathrow’s plans, and would offer more substantive advice if the government asked for it.

Mike Childs, head of policy at the climate charity Friends of the Earth, called the advice “dangerously optimistic,” adding that the aviation industry “will leap on this to argue that airport expansion is compatible with climate goals, even though the committee also stresses the importance of constraining the growth in passenger numbers.”

Both the UK government and the CCC expect engineered carbon removals to play a significant role in decarbonizing aviation, which is expected to be the UK’s highest-emitting sector in 2040, and for this to be funded in large part by the aviation industry. 

By the 2040s the CCC expects electricity will be almost entirely decarbonized in the UK, and the remaining sectors, including home technologies like electric cars and heat pumps, will rely heavily on actions by individual consumers.

The CCC downgraded its short-term projections for a heat pump roll out, expecting around 450,000 annual installations by 2030, compared to 1 million by 2030 in its previous modeling. It said meeting net zero would require significant funds in the short term, with expenditure peaking in 2029, but would save money in the long run. 

For example, in 2050, consumers would pay more upfront for heat pumps than they currently do for a boiler, but less for heating their homes and charging their cars because of the lower cost of energy. “This carbon budget will be the one where the savings to the economy from investing in these low carbon technology solutions start paying back to the economy,” said Pinchbeck.

(Updates with comments from government minister in fifth paragraph.)

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