Shell boss says Reeves is wrong on green’ Heathrow expansion who is right?

Rachel Reeves, no stranger to political turbulence, has been rebuked by Wael Sawan, the chief executive of Shell, for asserting that “green” aviation fuel will reduce the emissions impact of an expanded Heathrow and other UK airports.

- SEAN O'GRADY

The chancellor last week claimed, while fielding questions about why the government was pressing ahead with aviation expansion, that sustainable air fuel (SAF) would prove “a gamechanger in the way that we fly and the carbon emissions”.

But Sawan said: “The reality is that SAF is more expensive and therefore unless there are mandates – obligations on either customers or airlines – it is difficult to see a penetration that is going to be massive.”

Can both things be true?

Yes. As Sawan suggests, SAF can be a “game-changer” and help transform the impact of flying on climate change but will require someone, somewhere to bear the cost, often said to be about three times the cost of conventional fossil jet fuel. If the government were to subsidise it, the cost would be borne by taxpayers, which hardly seems fair or politically feasible.

If airlines, airports and aircraft manufacturers were forced to use it, the substantial extra burden would be passed on to consumers and shareholders. So the “game-changing” effect of SAF is not automatic.