Prof Julian Allwood: The only way to hit net zero by 2050 is to stop flying
The UK aviation industry this week pledged to bring its net carbon emissions down to zero by 2050 while growing by 70%, which is probably a lot of hype – to which they cannot yet be held accountable. But Professor Julian Allwood, an engineer from Cambridge University, argues that not only is it impossible and unrealistic for aviation to have zero carbon emissions, the only solution is to have a period with almost no flying at all. He says: “Let’s stop placing impossible hopes on breakthrough technologies, and try to hit emissions targets with today’s technologies.” And “There are 3 ways to deliver net-zero aviation: invent new electric aircraft, change the fuels of existing aircraft or take the emissions out of the atmosphere.” None of which can be done, at the scale necessary, any time before 2050, if at all. Long haul large electric planes will not be feasible for decades, if ever. There will not be enough spare renewably generated electricity to produce “green” hydrogen for planes. And “there are currently no meaningful negative emissions technologies. It requires more energy to recapture carbon dioxide from the atmosphere than was generated when it was released.” “Rather than hope new technology will magically rescue us” we need to “commit to halving flights within 10 years, hoping to phase them out entirely by 2050.”
The only way to hit net zero by 2050 is to stop flying
Dreaming of electric planes and planting trees will not save our planet
By Professor Julian Allwood – The writer is professor of engineering and the environment at Cambridge University
FEBRUARY 7 2020 (FT – Opinion, climate change)
The UK aviation industry this week promised to bring its net carbon emissions down to zero by 2050 while growing by 70 per cent, and Prime Minister Boris Johnson boldly predicted that “viable electric planes” would be available in just a few years.
But past experience with innovation in aviation suggests that such ambitious targets are unrealistic and distracting. The only way the UK can get to net zero emission aviation by 2050 is by having a substantial period of no aviation at all. Let’s stop placing impossible hopes on breakthrough technologies, and try to hit emissions targets with today’s technologies. Our recent report “Absolute Zero” draws on work at six British universities to explain how.
There are three ways to deliver net-zero aviation: invent new electric aircraft, change the fuels of existing aircraft or take the emissions out of the atmosphere.
Electric planes already fly. Solar Impulse 2, powered by solar cells flew one person round the world in 2016, but slow progress in photovoltaics mean this is unlikely to scale up. Demonstrations of short battery-powered flights with a few passengers will soon begin. However, the technology is in its infancy and aerospace is, rightly, a highly regulated industry. Commercial long-haul electric flights will not be operating at any significant scale by 2050.
Alternative fuels, such as hydrogen or synthetic kerosene, only deliver zero emissions flight if their production is powered by renewable electricity. Right now, green sources supply about 15 per cent of the world’s primary energy consumption. Over the next 30 years, while road vehicles, heating and industry are being electrified, there is unlikely to be spare clean power to make aviation fuel.
Finally, there are currently no meaningful negative emissions technologies. It requires more energy to recapture carbon dioxide from the atmosphere than was generated when it was released. Using renewable electricity to power carbon capture rather than to displace fossil fuels does not create a net reduction. And tree planting only goes so far: we must increase the total area of forest in perpetuity to produce a one-off reduction in atmospheric carbon dioxide.
So the commitment to net zero aviation by 2050 is really a commitment to zero aviation. Rather than hope new technology will magically rescue us, we should stop planning to increase fossil-fuel flights and commit to halving them within 10 years with an eye toward phasing them out entirely by 2050.
Taxing aircraft fuel at the level of the UK’s current road fuel tax would be a useful first step: I estimate that it would make flights up to four times more expensive.
Climate policy announcements so far have failed to account for the limited rate at which new technologies can reach significant scale. Fifty years after the Danes began developing wind turbines, they contribute just 2 per cent of world primary energy. Regardless of prices or incentives, new energy generation, transport and industrial processes require public consultation on regulations, land use, funding, environmental impacts and more. This all slows down their adoption.
We should embrace this reality and focus on innovations that are compatible with a zero-emissions future. Video-conferencing software cuts the need for travel but is undeveloped. Average car weight has risen steadily since 1990 and could be halved. Scrap steel is collected with little sorting and recycled into low-grade products, but it could be upcycled in renewable powered furnaces.
Bold announcements of “net-zero” targets by sunset industries such as fossil-fuel aviation cause confusion and delay the policies required to phase them out. They also distract us from innovations that can be implemented rapidly and buy us the time we need to develop real zero-emissions options.
UK air industry sets zero carbon target despite 70% more flights
Greenpeace criticises pledge from airlines, airports and manufacturers as ‘greenwash’
By Gwyn Topham (The Guardian) @GwynTopham
Tue 4 Feb 2020
The UK aviation industry has pledged to cut its net carbon emissions to zero by 2050 – despite still planning for 70% more flights over the next three decades.
Members of the Sustainable Aviation coalition, which includes most major airlines and airports, as well as aerospace manufacturers, will sign a commitment to reach net zero by mid-century. More than a third of the proposed net reduction will be achieved through offsetting.
A “decarbonisation road map” will be published outlining how aviation can cut its carbon footprint – replacing a previous road map that only committed the industry to halving emissions over the next three decades.
The plan sets out potential reductions coming from smarter flight operations, and new aircraft and engine technology – including some yet to be invented. Modernising airspace and developing sustainable aviation fuels will also contribute to reducing pollution.
About 25.8 million tonnes of CO2, out of 71.1 million tonnes set to be created annually by the UK sector, will need to be addressed through what Sustainable Aviation calls “market-based measures”, or offsetting.
The coalition forecasts that sustainable jet fuels, which are yet to be employed commercially, could meet almost a third of UK’s aviation fuel demand by 2050.
The transport secretary, Grant Shapps, described the commitment as a huge step forward in creating a greener future. He added: “Aviation has a crucial role to play in reducing carbon emissions, and with the help of new technologies, renewable fuels and our continued international cooperation … we’ll be able to strike that balance.”
Neil Robinson, the chair of Sustainable Aviation, said: “Climate change is a clear and pressing issue for people, businesses and governments across the world. We know aviation emissions will increase if decisive action is not taken, and that’s why UK aviation today commits to achieving net zero carbon emissions by 2050, through an international approach, working with governments around the world and through the UN.”
However, Greenpeace dismissed the move as “greenwash”. John Sauven, its UK executive director, said: “This whole strategy is a flight of fancy. Carbon offsetting is simply an excuse to carry on with business as usual while shifting the responsibility to cut emissions to someone else, somewhere else, and some other time. It’s greenwash pure and simple and ministers should be wary of lending it any credibility.”
British Airways’ owner IAG has already committed to net zero carbon emissions by 2050, while easyJet has gone further by already offsetting all flights.