'Outrageous greenwash' | No clear role for hydrogen as critics slam UK's net-zero aviation strategy
'Jet Zero' plan — described as 'pie in the sky' by one critic — leans on biofuels for 'guilt free flying', despite lauding the potential of H2
It defines SAF — a term often used interchangeably with biofuel — as “renewable or waste-derived aviation fuels that meet specific sustainability criteria and can be used in existing aircraft without significant engine modifications”.
The lack of substance behind the rhetoric suggests the UK may be quietly hedging its bets on pure hydrogen fuel in aviation on account of the many technical challenges — but without ruling it out.
On SAF, however, the Jet Zero strategy set the ball rolling. As well as putting an obligation on fuel suppliers to mix at least 10% SAF into aviation fuel mix by 2030, it also committed £1m ($1.2m) to support the delivery of the first net-zero transatlantic flight running on 100% SAF.
The obligation approach mirrors that taken by the UK government on road transport fuel, which now comprises 10% biofuels.
And a new £165m Advanced Fuels Fund will help meet a new pledge: to have five commercial-scale SAF plants under construction in the UK by 2025.
“Complete fantasy”
The strategy’s “guilt-free flying” mantra incensed environmental campaigners, who lambasted it as greenwash.
“On UK’s hottest day ever, government’s outrageous greenwash pours jet fuel on the flames,” tweeted Caroline Lucas, the UK’s only Green Party MP. “A ‘net zero aviation industry’ — while airport expansions and huge increase in passengers continue apace — isn’t a strategy, it’s pie-in-the-sky thinking.”
Climate campaign group Possible said: “All of the technology solutions in this aviation strategy are a complete fantasy.”
The group, which is highly critical of the land use issues surrounding biofuels, added: “‘Sustainable aviation fuels’? Extremely detrimental to the climate.
“The truth is there is only one method for reducing aviation emissions which we know works: reducing the number of flights.”
Round-trip efficiency
Some studies into the decarbonisation of aviation — which accounts for 2% of global emissions today — have suggested that hydrogen could play a role in short-haul flights which are out of range of battery-powered planes.
However, the round-trip efficiency of a green-hydrogen-fuelled combustion jet engine is just 33%, according to analysis from the Hydrogen Science Coalition, meaning that 100kWh of renewable energy will result in just 33kWh of energy delivered by the turbofan.
By contrast to the details-light approach to hydrogen in aviation, the UK has set ambitious targets for hydrogen production, earlier this year doubling its hydrogen production ambition to 10GW by 2030, half of which should be derived from near-zero-carbon electricity, rather than fossil gas.