Just as you can’t be certain if your budget airline flight will depart on time, whether the aviation sector will reach its net zero target remains equally as unpredictable.

A year ago, those working on aviation decarbonisation in Europe eagerly awaited the arrival of fuel mandates from EU and UK policymakers, which promised to set a clear direction of travel for the scaling of so-called ‘sustainable aviation fuels’, or SAFs. Though an important policy signal for the sector, the targets are not hugely ambitious: by 2030, jet fuel producers must supply at least 10 per cent ‘SAF’ in their aviation fuel mix in the UK and 5.3 per cent in the EU. When we consider the share that the highest integrity type of alternative fuels – e-fuels – need to make up, it is less than 1 per cent for both regions.

Yet since the announcement of these mandates, we’ve seen existing fuel producers BP and Shell withdraw investment from fledgling European SAF plants. Meanwhile, the likes of KLM and Virgin Airlines have been legally challenged and faced with greenwashing advertising bans for claiming that the use of these fuels – namely biofuels – is actually sustainable. It is unclear what the runway has ahead for 2025, but if the past year is anything to go by, there is sure to be some turbulence en route.

When we entered the aviation airspace last year, the prevailing narrative from the aviation industry was that ‘SAF’ was the best, perhaps only solution we have to addressing the climate impact of flying. Through consultation with leading organisations such as Transport & Environment, Opportunity Green and the European Climate Foundation – who have all been confronting the challenge of aviation decarbonisation for several years – it was clear that there were three things wrong with that assumption. Those three things form the basis of what is now Climate Catalyst’s aviation programme.

Not all SAF is ‘good’ SAF

For a sector that is global by nature, there isn’t actually a global standard for what defines a ‘sustainable’ aviation fuel. Each region and country has slightly different criteria for what is permissible under its own approach to life cycle assessments and fuel regulations – for example crop-based bioSAFs are strictly prohibited under EU regulation but some are permitted by US policy. At the international level, SAFs are defined by their performance comparable to conventional kerosene, not how sustainable the alternative fuel actually is. This makes for a challenging market to navigate for financiers looking to invest in SAF production or airlines looking to buy the fuel itself (all whilst trying to avoid greenwashing accusations).

There’s a category of alternative fuels – e-fuels – that can deliver between a 75 – 98 percent CO2 decrease compared to conventional fuel depending on how they are produced (and have non-CO2 benefits too). This is compared to just 27 – 55 per cent life cycle CO2 emissions reductions associated with biofuels – which are what many think of when they hear about ‘SAFs’ – depending on the feedstock used to produce the fuel*. And that’s before we consider other potential social and environmental implications of using crop based fuels.

E-fuels that have been created using captured CO2 and additional renewable energy to produce green hydrogen offer the highest potential for emissions reductions. As previously mentioned, these e-fuels also have sub-targets requiring them to be scaled within European mandates; in the UK, they must make up at least 0.5 per cent of total jet fuel demand by 2030, and in the EU that figure slightly rises to 0.7 per cent**. However, of the ~56 e-fuel plants awaiting construction in Europe, none have achieved a Final Investment Decision (FID), raising concerns as to whether these targets can actually be met through domestic production.

Investors are important advocates to government’s and to industry players within their portfolios. We have focused on equipping investors with information on the the policy landscape and the market potential of e-fuels, so that they can fully understand the varying sustainability and scalability of these alternative fuels for their corporate engagement and stewardship conversations with companies in the aviation supply chain, as well as consider their own future investment portfolios.

Looking forward, 2025 is a critical year for laying the groundwork to ensure the successful delivery of European fuel mandates and seeing plants reach FID. With renewable generation and hydrogen production increasing, Europe is well-suited to the domestic production of e-fuels as the highest integrity type of SAF. We will continue engaging the investor community about this opportunity as well as highlighting the importance of identifying the variability in different types of SAF when it comes to environmental impact. Importantly, we will start to build awareness of the blocking role that incumbent oil and gas majors are playing in the growth of this new market and how investors – alongside our civil society partners – can start to confront this inaction.

The dominance of the industry’s narrative needs challenging

Dominant industry narratives exist across all sectors, however that of the aviation industry is spread far and wide. The aviation industry has often relied on misinformation and misdirection to negate their responsibilities and their impact on the environment. They claim tight profit margins, an inability to absorb taxes on kerosene, spread fear mongering of more expensive holidays and tout technology – primarily SAF – as the silver bullet in tackling all emissions from air travel.

Our work is aimed at challenging this dominant narrative using creative communications and research backed messaging. The goal is to develop a playbook and framework for communicating on this issue, with tested messaging designed to resonate with key audiences across several countries in Europe.

We know that the majority of people care about climate change, and want to see more action to tackle the crisis we face. But they need truthful information to make informed decisions, and to know how to use their power as individuals, voters and consumers. That’s why we believe it is so important to unite the aviation climate community around new value-driven messages, to counter the misinformation being peddled and paint an ambitious vision for the future of the sector.

There are other solutions out there

The aviation industry was born out of human ingenuity, and it is likely that same ingenuity will be the key to unlocking significant and sustained emissions reductions from flying. For years, the leading aircraft manufacturers – Boeing and Airbus – have made incremental efficiency gains to their designs. But fundamentally, they have built aircraft designed to fly on fossil fuel. To tackle the emissions from aviation, the industry has focused on tackling the fuel, but there are some disruptive innovators who have developed exciting new ways to reimagine the way we fly entirely.

Zero emission flight (ZEF) technologies – such as those powered by hydrogen fuel cells or batteries – offer the potential to remove carbon emissions entirely (unlike ‘SAF’).

In September 2024, we held a convening between NGOs and leading UK innovators like ZeroAvia and Cranfield Aerospace Solutions to discuss the barriers to scaling ZEF, identify shared goals and visions for the role of ZEF and begin to align on priority areas for 2025. Focusing on the unique opportunity the UK presents in terms of a recent change of government and being home to some of the leading innovators in this space, we will continue to work with partners to shape activities around the themes of policy advocacy, investment and strategic communications with the aim of seeing significant progress made in ZEF over the next 12 months.

This is an exciting but also challenging time to be working on aviation decarbonisation. The dominance of existing industry players, not only through their strong lobby to policymakers but also their continued misinformation campaigns targeting customers and the general public, has seen progress towards net zero emissions stagnate. Moving into 2025, Climate Catalyst will continue to focus on increasing progress towards short and medium term reductions in aviation emissions by avoiding investment in the wrong type of ‘SAF’, while we challenge industry narratives and spur political will that could begin to address the unmitigated growth of the sector whilst allowing truly zero emission flight take off.

*The lower end of this spectrum are HEFA fuels or primary crop fuels such as those produced using corn, the higher end are waste-based fuels from materials that either don’t have any alternative use or would end up in landfill/alternative storage. **Under the UK’s SAF Mandate, 10 per cent of all jet fuel demand must be made of SAF, and of that 10 per cent, 0.5 per cent needs to be power-to-liquid PtL fuel, which equates to 5% of the total SAF requirement. Under the ReFuelEU Aviation Initiative, 6 per cent of jet fuel must be SAF, of which 0.7 per cent needs to be synthetic ‘e-fuel’ and equates to 11.67 per cent of the total SAF requirement.

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