9th November, 2021
Tomorrow is ‘transport day’ at the global climate talks currently taking place in Glasgow.
International aviation emissions aren’t on the official agenda at COP, as the UN’s aviation body, ICAO, is the lead organisation for developing measures rather than UNFCCC, which leads on climate change issues more generally. Most countries don’t include international aviation in their NDCs – the commitments they have made to cut their emissions in line with the Paris Agreement – though a recent legal opinion obtained by T&E argued that they should do so given their obligations to implement “economy-wide absolute emission reduction targets” in line with the temperature goal of the Paris Agreement.
Aviation is one of the hardest sectors to decarbonise. Pre-pandemic, the sector’s emissions globally were over 900MtCO2, more than twice those of the entire UK economy, and 2019 was a record year for aviation emissions in the UK and globally.
In the margins of the meeting, governments, industry and others will be hosting side events on aviation, largely to showcase what they are doing, with most of these taking place on Wednesday 10th November. Several events have been scheduled to talk up the carbon-cutting potential of new technologies and alternative fuels for aviation. The UK government will also be launching a declaration from a coalition of states who support the setting of a Paris-compatible long term climate goal at ICAO when it next meets in 2022. This is a useful initiative, although international action should not be a substitute for domestic target setting and measures. A summary of aviation-related events is here.
For an in-person, global event like the COP flights for some delegates are hard to avoid. The Government hopes to head off criticism of these flights this year, and promote the idea that the UK is leading efforts to decarbonise the sector, by collaborating with airlines and fuel suppliers to allow some Heads of State and VIPs to return home on flights using a blend of kerosene and so-called Sustainable Aviation Fuel (SAF) made from used cooking oil and other wastes. Ministers have sometimes described these fuels as paving the way to ‘guilt free’ flying.
But while avoiding some of the problems of earlier biofuels that competed with land for fuel or forestry, waste-based fuels are a dead end when it comes to aviation decarbonisation.
At best, waste-based fuels offer a ‘net’, not an ‘actual’ emissions reduction. At least as much CO2 is emitted when they are burned as from kerosene, so any emissions saving comes from the assumption that CO2 has been absorbed historically by organic matter that provides the energy in the waste. Using waste fuels does not cut CO2 emissions now.
Many of the claims of big emissions savings (sometimes greater than 100%) from using these fuels arise from assumptions that they help avoid the release of methane – a powerful greenhouse gas that can be generated by food waste in landfill. But converting these wastes into aviation fuel isn’t a net-zero strategy given the CO2 it then releases. To achieve our climate targets we’ll need both to cut methane emissions and decarbonise flying.
We also need to try to avoid generating waste, so this isn’t a scalable solution for powering aviation. Used cooking oil has a number of other applications, and there’s only so much chip fat around.
Earlier this year, the Government committed to formally include international aviation and shipping emissions in the targets set under the UK Climate Change Act, from the start of the sixth carbon budget (which covers the years 2033-37). It has separately committed to net zero aviation emissions by 2050.
Ministers have not yet, however, set out a credible plan for achieving this. Last autumn the Government published what it called a ‘jet zero’ strategy which talked about zero emission planes, and included ambitious scenarios for the take-up of new technologies. But so far it has no proposals for overcoming the cost and other barriers to their rollout, and it has resisted recommendations from the Climate Change Committee to limit aviation demand growth to help achieve the target.
Aviation is likely to stand out increasingly as a problematic sector when it comes to achieving net zero by 2050, and even more so if the focus is on nearer-term dates like 2030 as technologies to decarbonise flight are still in their infancy, as are those that will be needed to remove CO2 from the atmosphere to balance any ongoing release of CO2 from planes. Just 1% of the global population generate around half of global aviation emissions, with wealthy nations such as the UK bearing the most responsibility for the problem. Some of the key measures that will be necessary to tackle aviation emissions include the following.
For many of those who fly, the pandemic has forced a rethink both of how to connect for business, and of the possibilities of holidaying nearer to home. But to avoid retuning to the pre-pandemic trajectory flight numbers will need to be limited. The UK Government remains so adverse to the concept of behaviour change that it quickly withdrew an internal document recommending steps such as promoting domestic tourism and discouraging frequent flying which it claims was accidentally published alongside its ‘net zero’ strategy for the UK. Such measures are hardly radical though. The International Energy Agency’s most recent vision for achieving net zero emissions argued for reductions in business travel and long-haul holidays in advanced economies, for example
Ending airport expansion
The Climate Change Committee has recommended no net airport expansion in the UK, highlighting that enough capacity exists already to meet the maximum level of aviation demand it considers compatible with achieving net zero. At present, seven UK airports are lining up to expand and a major airport intends to progress its plans in 2022. Last weekend, communities protested against expansion at ten UK airports.
Making airlines accountable for their emissions
While the Government has said it will include international aviation in the sixth carbon budget (2033-37), action is needed now. Currently fuel for international flights is untaxed and most carbon emissions from flying bear no financial penalty. To overcome some of the hurdles to developing the zero carbon technologies needed for this sector either airlines will need to start putting in some serious money, or governments will need to start charging hefty penalties for emissions. Or both.
Developing genuinely zero carbon fuels and technologies
For aviation to operate in a net zero future we’ll need rapid development of technologies that are scarcely beyond the testing stage. Liquid e-fuels made from carbon captured from the air and combined with green hydrogen; hydrogen-powered aircraft (for short haul travel); and carbon capture and storage could all have a part to play. But if governments remain more committed to maintaining cheap flights and to supporting passenger growth than they are to achieving net zero aviation it’s hard to see these technologies getting the investment they need.