The UK is to set in law what it describes as the world’s most ambitious climate change target and for the first time will include emissions from international aviation and shipping. In accepting the recommendation of its advisory Climate Change Committee, the UK government is pledging to reduce overall emissions by 78% by 2035 compared to 1990 levels. By incorporating the UK’s share of international aviation and shipping emissions in its newly announced sixth carbon budget, which covers the period 2033-2037, the government said the two sectors were an important part of its decarbonisation strategy that would allow for their emissions to be accounted for consistently. The UK has already committed to reduce overall emissions in 2030 by at least 68% compared to 1990 levels through its Nationally Determined Contribution (NDC) under the Paris climate agreement – the highest reduction target made by a major economy to date – but it does not intend to include the UK’s share of emissions from international aviation and shipping in its NDC, in line with UN convention. The lead UK climate negotiator at the upcoming COP26 told journalists this week the UK would continue to work through ICAO and IMO to achieve emission reductions in line with Paris climate goals.

“We want to continue to raise the bar on tackling climate change, and that’s why we’re setting the most ambitious target to cut emissions in the world,” said Prime Minister Boris Johnson. “We want to see world leaders follow our lead and match our ambition in the run up to the crucial COP26 climate summit, as we will only build back greener and protect our planet if we come together to take action.”

Last November, Johnson outlined a ‘Ten point plan for a green industrial revolution’, one of which is to develop a strategy for the aviation sector to reach net zero emissions through aerospace technology and sustainable aviation fuels (SAF). This included the setting up of the government-industry Jet Zero Council. The government is planning to consult on its aviation decarbonisation strategy shortly, possibly in May, and then in 2025 hold a further consultation on a SAF mandate with a potential start date that year.

The Climate Change Committee (CCC) says the 68% reduction by 2030 commitment under the UK NDC would be 64% if international aviation (based on emissions from departing flights) and shipping were included. International emissions from both sectors totalled around 45 MtCO2e in 2019 and together with domestic emissions made up 10% (aviation 7% and shipping 3%) of overall UK emissions. Although emissions from international aviation and shipping are treated separately by the UN, points out the CCC, “they must be addressed if the temperature goal of the Paris Agreement is to be met,” it asserts. “The UK’s NDC should include clear commitments to act on emissions from international aviation and shipping, including both long-term and interim targets.”

In its 450-page advice in November to the government on its sixth budget, the Committee presented scenarios on how the aviation sector could reach net zero, based on what it describes as a recommended ‘Balanced Net Zero Pathway’. Under this pathway, it is assumed the aviation sector returns close to pre-pandemic demand levels by 2024 and thereafter emissions gradually decline to reach 23 MtCO2e per year by 2050, based on a modest 25% growth in traffic by 2050 compared to 2018 levels, rather than an unconstrained forecasted growth of 65% over the same period. Those remaining 23 MtCO2e emissions will need to be offset with GHG removals via nature-based and engineered options, says the guidance.

The CCC sees demand management playing a critical role in ensuring emissions continue to decrease, particularly while efficiencies and SAF scale up, and so this pathway is predicated on no net increase in UK airport capacity, so that any expansion is balanced by reductions in capacity elsewhere in the UK. It also assumes fuel efficiency per passenger improves at 1.4% per annum during the period, 9% of total aircraft distance in 2050 being flown by hybrid-electric aircraft and SAF contributes 25% of liquid fuel consumed in 2050, with two-thirds coming from biofuels and the remainder from synthetic jet fuels.

Sources of abatement in the CCC’s Balanced Net Zero Pathway for the aviation sector:

The CCC analysis also explores alternative pathways based on different contributions from efficiency and technology improvements, SAF take-up and passenger demand. It estimates that under the Balanced Net Zero Pathway, additional investment of around £390 million a year ($540m) in 2035 and £2,750 million ($3.8bn) a year in 2050 will be required for efficiency improvements and hybridisation. Further operational costs of using SAF, given their additional cost above fossil jet fuel, are likely to be incurred of £470 million a year in 2035 and £1,520 million a year in 2050. The costs are offset by operational and fuel efficiency savings of £1,230 million a year in 2035 and £2,750 million a year in 2050. In earlier years, efficiency gains significantly outweigh added fuel costs.

The cost of SAF priced with marginal GHG removals might add £35 to a return ticket from London to New York in 2050 under the Balanced Pathway, minus £21 of fuel savings from improved efficiency, estimates the CCC. If full decarbonisation was paid for using GHG removals to offset residual emissions, this may add a further £41, giving a net added cost of £56.

While welcoming the government’s climate ambition on the new target and stressing the UK aviation industry remained fully committed to achieving net-zero carbon emissions, the Chair of the cross-sector coalition Sustainable Aviation, Adam Morton, said significant government support was needed.

“This effort requires a strong long-term partnership with government – including through the Jet Zero Council – that boosts support for industry investment over the coming months and through the next critical decade,” he said. “This means providing the right policy support for SAF, increasing investment in R&D for new aircraft and engine technologies, including hydrogen and electric aircraft technology, and accelerating airspace modernisation.

“Aviation is a uniquely global industry that requires global solutions to avoid simply moving emissions from one country to another, with no appreciable impact on climate change. For this reason, the UK aviation industry is also pushing for a 2050 commitment to net zero emissions at next year’s ICAO Assembly.”

The inclusion of international aviation emissions in the UK carbon reduction targets was welcomed by NGOs Aviation Environment Federation (AEF) and Transport & Environment (T&E).

“Aviation’s share of national emissions has been growing steadily as other industries have begun to decarbonise and while some airlines and airports have made climate pledges, there had been no means of holding them to account for these aspirations,” said AEF, which had campaigned for the inclusion.

“This should mark the beginning of the end for fossil-fuelled aviation,” said Cait Hewitt, Deputy Director, AEF. “After many years of slipping the net when it comes to climate change, and expecting special privileges, airlines will now need to start planning for a very different future.

“Including international aviation in UK climate law gives a strong message from ministers that all sectors of the UK economy need to be on the same path towards net zero emissions. Now the government will need to make sure that’s delivered.”

AEF suggested the government should consider setting annual emissions targets for airlines, a review of policy on airport expansions, new financial measures to limit flying demand, such as an air miles tax, and measures to support staff currently employed in aviation to transition to green jobs where appropriate. Rather than focusing on carbon offsetting, it said, the industry could ramp up R&D into zero carbon energy options for aviation, such as synthetic fuels, and plan to deliver carbon capture and storage of remaining emissions.

T&E said the decision to include international aviation and shipping into the UK carbon budgets was a “very positive step towards reducing carbon pollution” from the two sectors and “closed a loophole they had been allowed to escape”.

“Properly accounting for the emissions is essential, but we now need meaningful action to control GHG releases and prevent future emissions rising above pre-pandemic levels,” said Matt Finch, T&E’s UK Policy Manager. “In the process, the UK can become a world leader in zero-emission fuels for planes and ships.”

Coinciding with the UK pledge, negotiators from the European Council and the European Parliament have reached a provisional agreement that will set into EU law the objective of a climate-neutral EU by 2050 and a collective net GHG emissions reduction target – emissions after deduction of removals – of at least 55% by 2030 compared to 1990, and an aspirational goal to strive to achieve negative emissions after 2050. They also agreed the Commission would engage with sectors of the economy that choose to prepare indicative voluntary roadmaps towards achieving the Union’s climate neutrality objective by 2050. (The European aviation industry released its Destination 2050 roadmap in February.) The provisional agreement on the climate law is subject to approval by the Council and Parliament before adoption.

Brussels-based T&E urged the EU to follow the example of the UK. “The UK is showing how to take responsibility for its climate impact. The EU should incorporate aviation and shipping in its climate law or relinquish its aspirations for climate leadership,” said Andrew Murphy, T&E Aviation Director. “If the UK, with an economy so reliant on aviation and shipping, can do this then Europe has no excuses.”

Top photo: British Airways A350 tail fin

There should be no net expansion of UK airport capacity unless the sector is on track to sufficiently outperform its net emissions trajectory and can accommodate the additional demand, says the UK’s advisory Climate Change Committee (CCC). In a major report on recommended policies to achieve the UK’s overall net zero emissions by 2050 target, the CCC says demand management will be required to constrain UK aviation growth to 25% growth by 2050 from 2018 levels unless efficiency and sustainable aviation fuel take-up can be developed quicker than expected. The Committee recommends emissions from international aviation be included in UK carbon budgets and the net zero target by next year. The UK should also work with ICAO to set a long-term emissions goal consistent with the Paris Agreement, strengthen CORSIA and align the scheme to this goal in 2023.

The policies for aviation are set out in the Committee’s advice to government on the nation’s Sixth Carbon Budget – the legal limit for UK net GHG emissions over the 2033-37 period. This will necessitate a requirement for an overall 78% reduction in UK emissions by 2035 relative to 1990, equivalent to a 63% reduction from 2019, which it says would place the UK on a path to net zero by 2050 at the latest.

On aviation, the Committee’s report acknowledges the UK industry’s commitment through its Sustainable Aviation coalition to the net-zero goal for 2050 although this is not yet a policy goal for the government, which is due to consult in 2021 on its intended Aviation Decarbonisation Strategy.

“Higher-level strategic gaps include the lack of formal inclusion of international emissions in UK carbon budgets and the net zero target, and the need for a sector emissions trajectory to inform demand management and airport capacity policies,” points out the Committee. “Further research is also needed on non-CO2 effects and potential mitigation options.”

UK government policy has been not to include emissions from international flights in the carbon budgets pending developments with UN negotiations on ICAO’s CORSIA scheme but the Committee is strongly recommending a change. The Chairman of the CCC, Lord Deben, told journalists ahead of the publication of the report that the UN structure demanded international emissions from aviation and shipping be excluded from Nationally Determined Contributions under the Paris Agreement.

“What the Committee is saying very clearly is that the UK government must take up the cudgels in order to include the emissions from these two sectors. If you don’t include them, then you are falsifying the fact when it comes to net zero, so we need to make that change,” he said. “We’ve really got to get aviation and shipping into the system, and pretty quickly.”

Existing UK aviation policy has been focused on establishing the Jet Zero Council with an ambition for zero-emissions commercial flight, match-funding for aircraft technology development and traded certificate price support for sustainable aviation fuels (SAF) under the Renewable Transport Fuel Obligation (RTFO). Investments have also been made in a grant-funding competition for SAF production and the FlyZero aircraft technology initiative. There are also plans for a SAF clearing house to enable the UK to certify new fuels and a consultation on a SAF blending mandate for a potential start in 2025.

However, the RTFO inclusion is unlikely to drive significant development of renewable jet fuels and there is a lack of larger-scale deployment support and policy framework for these fuels, says the Committee. It advises the government to set out a policy package for supporting the near-term deployment of SAF facilities in the UK that may involve capital or loan guarantee support, and to transition to a more bespoke policy than the RTFO. A SAF blending mandate could ultimately provide more certainty to SAF plant investors than the RTFO, it believes. SAF facilities should have to install carbon capture and storage (CCS) or be built CCS-ready in order to maximise GHG savings, it adds, and SAF must meet strict sustainability standards.

The report says carbon pricing will be required to incentivise the transition to net zero although there are issues around equitable distribution of costs. Aviation fuel faces no taxes and international flights beyond EU borders are outside the scope of the EU ETS, so do not face a carbon price, it points out. The Committee noted that the recent citizens’ UK Climate Assembly favoured a frequent flyer levy to address fairness concerns.

The Committee proposes that in the long term, an economy-wide emissions trading scheme with a cap set to zero emissions would be a plausible way of balancing emissions and pricing carbon for sectors like aviation, so providing financial support for GHG emissions removals from, for example, woodland or peatland restoration, or engineered removals such as bioenergy with carbon capture and storage (BECCS).

Given expected developments in efficiency and SAF deployment, the Committee advises the government to implement a demand management policy to constrain UK aviation growth to 25% by 2050 from 2018 levels for the sector to contribute to the UK net zero goal. If efficiency and SAF develop quicker, it may be possible for demand growth to rise above 25%, provided that additional non-CO2 effects are acceptable or can be mitigated, it says.

“The government should assess its airport capacity strategy in the context of net zero and any lasting impacts on demand from Covid-19. Investments will need to be demonstrated to make economic sense in a net zero world and the transition towards it,” says the report.

“Unless faster than expected progress is made on aircraft technology and SAF deployment, such that the sector is outperforming its trajectory to net zero, current planned additional airport capacity would require capacity restrictions placed on other airports. Going forwards, there should be no net expansion of UK airport capacity unless the sector is assessed as being on track to sufficiently outperform a net emissions trajectory that is compatible with achieving net zero alongside the rest of the economy, and is able to accommodate the additional demand and still stay on track.”

Baroness Brown, Deputy Chair of the Committee, told journalists: “There is a limit on the aviation emissions we can afford so if it is crucial for our economy to have, say, more capacity in the airport system in London then that would mean reducing capacity elsewhere – it’s about no net increase in the capacity. We do assume there can be some growth in aviation and we’ve looked very carefully at the conclusions of the Climate Assembly and the assumptions we have made are closely aligned with it on issues like aviation.

“The aviation industry is hugely important to this country and we consider there will be some very important advances in technology and synthetic fuels, and we are keen that the government supports their development. As you go forward in time, the benefits from improving aircraft efficiency will also start to outweigh the costs of reducing aviation emissions. It’s not a gloomy story about aviation – there are opportunities but not for rampant growth in terms of flying, and certainly not in the short term until we have the solutions in place.”

On aviation’s non-CO2 effects, the report recommends work should be supported to reduce the scientific uncertainties and fund research into mitigation options. As a minimum goal, there should be no additional non-CO2 warming from aviation after 2050 and possibly earlier with a policy intervention.

“Alongside efforts at ICAO, the Aviation Decarbonisation Strategy and the package of domestic policies, plus parallel progress on a mechanism for deploying GHG removals in the UK, should put UK aviation emissions on track to contribute fully to meeting the Sixth Carbon Budget and the net zero target,” concludes the report.

Responding, Sustainable Aviation’s Programme Director, Andy Jefferson, commented: “We were the first national aviation group in the world to pledge to achieve net zero by 2050 in February of this year, and our members are fully committed to decarbonising aviation in line with global targets. 

“We are currently assessing potential interim targets for 2030, and plan to announce this during 2021 once we have clarity on a range of dependent factors. This includes the trajectory of the post-pandemic recovery, the next phase of the EU Emissions Trading System and the global CORSIA scheme. 

“We have a clear Road-Map for how to achieve net zero in aviation through SAF, new cleaner aircraft and modernisation of airspace. The right action from government now on SAF in particular will have a marked effect on our ability to set and achieve ambitious interim targets for decarbonisation.”

Cait Hewitt, Deputy Director of UK environmental group the Aviation Environment Federation, said: “The CCC’s advice is clear: the government needs to call time on airport expansion. Zero-carbon aviation is currently an aspiration, not a reality, and while it’s right to pursue new technologies for cutting emissions, we can’t rely on these coming through fast enough to decarbonise the sector without also reducing aviation demand.

“Our analysis shows that current and planned UK airport expansions could increase aviation CO2 emissions by nearly 9 Mt a year in 2050 compared to a situation with no expansion.

“The aviation sector has taken a huge hit from the Covid pandemic but jobs per passenger had already been falling for many years. The government now needs to sharpen its focus on how to build the zero-carbon industries – and jobs – of the future.”

Photo: Heathrow Airport