Not far from the hallowed spires and research labs of Oxford University, two workers in overalls and hard hats are searching for air travel’s “holy grail” – climate-friendly airline fuel made from nothing but carbon dioxide and green hydrogen.
That is how OXCCU chair Alan Aubrey describes the Oxford-based company’s mission to scale up its nascent production of so-called e-SAF, a synthetic hydrocarbon fuel that backers hope could one day become a viable, green alternative to traditional kerosene jet fuel.
“The beauty of this is that the inputs – CO2 and hydrogen – are at least theoretically unlimited,” the company’s CEO Andrew Symes told reporters during a visit to OXCCU’s experimental plant last year. “This industry – yes it starts small – but it can grow and scale and become very big.”
E-SAF can reduce planet-heating carbon emissions by up to 90% compared to conventional jet fuels. In contrast to more established forms of SAF, e-SAF does not require vast quantities of raw materials such as used cooking oil (UCO) or – more controversially – agricultural products such as sugar-based ethanol, soy or palm oil.
It is easy to see the fledgling industry’s appeal as airlines and governments fret over how to tackle air travel’s growing carbon emissions. They are closely watching the progress of startups such as OXCCU, whose backers include United Airlines, Saudi energy giant Aramco and Italy’s Eni.
Policymakers in the European Union and the UK are also taking note, and fuel providers are being mandated to supply growing amounts of e-SAF, starting with 0.2% in the UK in 2028 and 0.7% in the EU in 2030.
So far, e-SAF has only been used for a few high-profile test flights. In 2021, Dutch airline KLM used 5% SAF on a flight from Amsterdam to Madrid, and the British air force was the first to power a plane entirely on e-SAF when a two-seater made a short trip around a private airport.
But scaling up synthetic fuel production could be a long haul.
To fly or not to fly?
E-SAF remains prohibitively expensive to produce and so far its use has mainly been limited to demonstration projects, like OXCCU’s plant at Oxford Airport. Critics say it could be decades away from becoming commercially viable.
Producing green hydrogen from water to make the fuel requires huge amounts of renewable electricity, which the industry’s detractors say is a waste of scarce green power resources.
Such obstacles, they say, make it a distraction from the most obvious solution to aviation emissions: flying less.
Aviation’s Green Dream: Read our investigative series on Sustainable Aviation Fuel
“The idea that we can magic up this gigantic renewable capacity to produce e-fuel … it’s just not doable, it’s not going to be affordable, and it makes no sense from the perspective of using resources,” said Alethea Warrington, a campaigner on aviation issues at Possible, a UK-based NGO that promotes climate action.
Some climate campaigners are more positive about e-SAF. Aoife O’Leary, head of climate think-tank Opportunity Green, said there is a need to “deal with the unsustainable growth of aviation”, but that we should “also decarbonise the flights that exist”.
Acknowledging the huge renewable energy requirements needed to make green hydrogen, she said that “if paid for by the industry, then it would be additional to the renewable energy that exists otherwise”.
Aviation industry body IATA, the International Air Transport Association, urged governments in a recent statement to redirect into renewables “a portion of the $1 trillion in subsidies that governments globally grant for fossil fuel” and to develop policies“ to ensure SAF is allocated an appropriate portion of renewable energy production”.
The Possible group has called instead for measures to limit flight numbers, for example, a frequent flyer tax and efforts to promote rail transport.
But sweeping policies to reduce flying would be unpalatable for many governments and painful for passengers. Surveys from Europe and the US suggest that about a quarter of flights are taken to visit friends and relatives, and globally about 95% of flights are longer than 500 km (310 miles) – making other forms of transport less practical.
In the meantime, the world’s appetite for flying continues to grow, spurring efforts to find a way to tackle the carbon footprint of aviation – today the cause of about 2.5% of all energy-related emissions.
On its current trajectory, the aviation industry is on course to blow a big hole in the world’s goal to limit global warming to 1.5 degrees Celsius. According to the International Civil Aviation Organization, a UN agency, the sector’s emissions could double or even triple between 2015 and 2050.
That is partly because other sectors, such as road transport and power generation, are cutting their emissions by switching to renewable electric energy – still a distant technological prospect for commercial aircraft.
Fuel from air and water
Concern that plant-based SAF could increase competition for land and raise deforestation risks might boost efforts to ramp up e-SAF production.
New rules in the EU and the UK say only waste products such as UCO should be used to make SAF, but experts and industry insiders told an investigation by Climate Home News and its partner The Straits Times that in key UCO supplier Malaysia, unused or barely used palm oil is being passed off as waste oil.
In contrast, synthetic fuel is made by passing an electric current – produced with renewable electricity – through water, splitting it into hydrogen and oxygen gas. The oxygen is released harmlessly into the atmosphere, while the hydrogen is captured and mixed with carbon dioxide (CO2) to make the hydrocarbon jet fuel.
E-SAF producers such as OXCCU and US-based Twelve, which is set to supply Alaska Airlines and International Airlines Group, source their CO2 from industries that produce it as a waste product.
“It’s essentially getting two uses out of the carbon before it goes up into the atmosphere,” Symes said, adding that an even better option would be using technology to capture CO2 directly from the air, which would be fully circular and carbon neutral.
While OXCCU buys its green hydrogen, Twelve is planning to make its own at its factory in the US Pacific Northwest. “That’s something we’ve invested a lot of time and money into over the past few years,” the company’s vice president of business development Ashwin Jadhav told Climate Home.
Green hydrogen challenge
Scaling up green hydrogen production will be a “real challenge”, despite e-SAF’s “immense” potential, said Azim Norazmi, climate policy manager at IATA.
With the global aviation industry’s net-zero goal just 25 years away, he said plant-based biofuels – not e-SAF – will be the “biggest contributor” to meeting that target.
Aurelia Leeuw, Opportunity Green’s EU policy director, said one of the issues holding back e-SAF production is that airlines generally only want short-term contracts of around a year, while producers need longer-term certainty to justify investments in ramping up output.
The European Commission is expected to announce a sustainable aviation plan in the next few months. Leeuw and others are hoping this will help solve the problem by bringing international aviation into the EU’s Emissions Trading System (ETS) and using the funds raised from imposing charges on airlines to buy large quantities of e-SAF. An intermediary – such as the European Commission – would then sell the fuel on short-term contracts.
The idea under consideration would bring flights taking off in Europe that land outside the continent into the ETS, generating more funding from the aviation industry to support investment in e-SAF.
Leeuw said demand for e-SAF is also being held back by airlines and fuel suppliers assuming that the European Commission will water down its mandates and not fully apply penalties for fuel suppliers that do not meet them. The size of these penalties will depend on the price difference between conventional jet fuel, SAF and e-SAF – but are likely to be thousands of dollars per tonne, according to Brussels-based NGO Transport & Environment.
“The European Commission is saying the [e-SAF] targets are not up for debate. But the airlines and oil and gas incumbents are lobbying them hard and playing off the uncertainty that they themselves are creating,” she said.
“There must be no doubt that these… are the targets – and those are the penalties,” she added.
This article was developed with the support of Journalismfund Europe.
The post Air travel’s ‘holy grail’: Jet fuel made from CO2 and water prepares for take-off appeared first on Climate Home News.
Air travel’s ‘holy grail’: Jet fuel made from CO2 and water prepares for take-off
The Endangered Species Committee, known as the God Squad, issued a rare exemption from compliance with the Endangered Species Act for oil and gas activities in the Gulf of Mexico.
Environmental groups are suing the Trump administration over its decision to exempt oil and gas drilling in the Gulf of Mexico from complying with the Endangered Species Act, a move they say threatens both the coastline region and the law designed to protect threatened plants and animals.
Environmental Groups Take Trump Administration’s ‘God Squad’ to Court
The ocean’s fastest and most formidable predators might also be the most physiologically vulnerable to warming waters, researchers warn.
The evolutionary edge that fueled great white shark dominance for millions of years could soon become its greatest downfall.
Climate Change
China Briefing 16 April 2026: Billions for grid | Petrochemical plan | China’s high-seas bid
Welcome to Carbon Brief’s China Briefing.
China Briefing handpicks and explains the most important climate and energy stories from China over the past fortnight. Subscribe for free here.
Key developments
Surge in grid investment
TRILLION-YUAN ERA: China’s two largest power grid operators invested a total of 167.5bn yuan ($24.5bn) in the first quarter of 2026, reported state broadcaster CCTV. State Grid said that during this period it spent more than 10bn yuan on connecting “new energy” projects to the grid, up 50% from last year, reported Shanghai-based news outlet the Paper. The two state-owned enterprises (SOEs) plan to invest 1tn yuan ($146bn) annually over the 15th five-year plan period (2026-2030), said finance news outlet Yicai.
POWER CURBED: However, in what Bloomberg called a “clear signal that the grid is struggling to absorb all the extra power from the rapid growth in renewables”, solar and wind utilisation rates – the percentage of total power generated by a source that is used by the grid – fell again at the start of the year. They stood at 90.8% and 91.5%, respectively, in January and February 2026, according to a post by an SOE-linked research institute republished by energy news outlet International Energy Net. The rates are now “approaching [minimum] limits that the government had relaxed only two years ago”, added Bloomberg.
SIX PROVINCES SUPERVISED: A recent meeting of the National Energy Administration (NEA) concluded that China’s renewable installations had seen “steady growth” in 2026, adding that the body must make “sustained efforts” to “expand” investment in renewable power, reported International Energy Net. Separately, International Energy Net also said that the NEA will increase “supervision” of the power sectors in six provinces – Hebei, Jilin, Xinjiang, Fujian, Hunan and Guangdong. The outlet said this would entail scrutinising how they implement “energy conservation and carbon reduction” tasks, with a “focus” on coal plants, how they construct large clean-energy bases and their consumption of new energy, as well as their power infrastructure and markets.
Conflict spurred cooperation with China
CHINA ‘WINNING’: In Vienna, Chinese climate envoy Liu Zhenmin told state news agency Xinhua that the Middle East conflict has created an urgent need for countries to rethink energy security strategies and accelerate the energy transition. Xinhua also cited Liu as warning against over-reliance on a single source of energy imports. Meanwhile, state broadcaster CCTV published a segment arguing that a “greener” system will “provide a strong guarantee” for energy security, although it did not mention the conflict. Several outlets have continued to highlight how low-carbon energy has helped China weather the conflict and boosted sales of Chinese technologies, including the New York Times, Wall Street Journal, Associated Press, Indian Express, Washington Post and Bloomberg. Semafor said China was “winning the global energy war”.
MANY MEETINGS: United Arab Emirates crown prince Sheikh Khaled bin Mohamed bin Zayed Al Nahyan and Chinese president Xi Jinping discussed how to “prevent further impacts” from the conflict on energy security, said Xinhua. Australian prime minister Anthony Albanese said he addressed “regional energy security” with Chinese premier Li Qiang, reported Reuters. A post by China-Russia Information Net on nationalist media outlet Guancha quoted a Chinese diplomat in Russia telling reporters that “current dramatic changes in the international situation” are causing the two countries to discuss “further energy cooperation”. The Philippines is continuing to consider “oil and gas cooperation” with China, despite territorial disputes, Reuters also reported.
‘PROFOUND’ IMPACTS: Energy administration head Wang Hongzhi wrote a chapter in a “study guide” to the 15th five-year plan, published by industry outlet China Power News Net, in which he noted that “geopolitical conflicts are profoundly reshaping the global energy landscape”. He added that “traditional fossil fuels must continue to serve as a safety net while [China] simultaneously accelerates efforts to transition [to clean energy sources]”. Environment minister Huang Runqiu wrote in the CPPCC Daily, the official newspaper for the advisory body Chinese People’s Political Consultative Conference (CPPCC), that China will “earnestly” carry out “carbon peaking actions” in the next five years. Huang also said that, with “concerted efforts”, China’s 15th five-year plan targets are “achievable”.
Petrochemical plan published
UPGRADE DEADLINE: China issued a plan for either upgrading or phasing out “outdated” petrochemical plants by 2029, reported Reuters. It added that the plan did not confirm explicitly “how many plants may be upgraded or phased out”. The news outlet Economic Daily said that, according to the document, China would focus on upgrading or phasing out outdated capacity “as determined in 2025”, while also developing a “long-term working system” for assessing the industry. According to the full document, published on the Ministry of Industry and Information Technology (MIIT) website, carbon-emission assessments were part of the selection criteria, with policymakers planning on “developing or revising” further standards for carbon emissions under the plan.
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CHEMICAL OVERCAPACITY: The Paper quoted MIIT official Chang Guowu telling reporters that the plan will address the “low standards of design and construction” and “outdated processes” in older plants that lead to “significant” environmental risks. Xinhua said that, of China’s more than 27,000 petrochemical plants, “more than 1,600…outdated facilities” were reported in 2025, 600 of which required upgrading. Chemical news WeChat account WeLink Chemicals noted the policy was released against a backdrop of “overcapacity and declining demand for road transport fuels”, with the government having “stepped up efforts to curb overcapacity” in 2025.
More China news
- TARGET PLEDGED: China will cut the carbon intensity of its international shipping vessels by at least 15% by 2030 compared to 2025 levels, said climate outlet IdeaCarbon. It said China will also “significantly enhance” its influence in emission reduction talks at the International Maritime Organization.
- SANCHEZ VISITED: China and Spain “can contribute to finding solutions” for environmental issues, Spanish leader Pedro Sanchez told Xi Jinping, according to the Associated Press. Ahead of the meeting, Sanchez also argued China should play a more substantial role on climate change, said the Singapore-based Straits Times.
- CHINA COMMITTED: Huang Runqiu reaffirmed China’s support, “as always”, for global climate governance in a meeting with UN advisor Selwin Hart, said the Paper.
- FUNDING HALTED: The EU “quietly” approved a plan to prevent EU funds being provided to “clean technology projects containing Chinese inverters”, said the Hong Kong-based South China Morning Post.
- AI UNVEILED: Chinese researchers developed a “first-of-its-kind artificial intelligence model designed to track carbon emissions”, reported Xinhua, adding that it “could shift the balance of power” in global climate negotiations, such as by quantifying the “embedded carbon” of products that developed countries import from China.
- CONTROLS CONSIDERED: China is deliberating “limiting exports” to the US of the equipment needed to make solar panels, according to Reuters.
Spotlight
The debate over China’s bid to host the “high seas” treaty
The final preparatory commission for the Biodiversity Beyond National Jurisdiction (BBNJ) agreement has closed, laying the groundwork for the treaty’s first conference of the parties (COP1).
One key agenda item was China’s presentation of a bid to host the secretariat. In this issue, Carbon Brief examines the debate surrounding the bid.
The BBNJ agreement, also known as the High Seas Treaty, governs the sustainable use and conservation of the “high seas” – marine areas outside national jurisdictions – with a new United Nations (UN) body established to oversee enforcement.
As well as facing significant impacts from climate change, the ocean plays an important role as a carbon sink, absorbing around 29% of man-made emissions.
The treaty “recognis[es]” the need to address oceanic biodiversity loss and ecosystem degradation, according to previous Carbon Brief analysis, identifying key impacts from climate change, acidification, pollution and “unsustainable” use.
It aims to encourage conservation and sustainable use of marine biodiversity in the high seas, such as by managing “marine genetic resources”, creating protected areas in the ocean, developing environmental impact assessments and facilitating capacity-building and transfer of marine technology.
China’s bid
China’s bid to host the secretariat focused on its “sustainability efforts” and “commitment to multilateralism”, reported the Earth Negotiations Bulletin.
The country’s bid document drew attention to several of its emission-reduction efforts, including “green shipping corridors” and strengthening carbon sinks through protecting mangroves, seagrass beds and coral reefs.
In a speech, Chinese ambassador to the UN Fu Cong said that the bid “reflects China’s unwavering support” for multilateralism, adding that a successful Chinese bid would lead to the first UN-related body headquartered in the Asia Pacific region. He said:
“That means it will not only be welcomed, but also be prioritised. It will have the full backing from all levels of government in China and its people.”
Li Shuo, director at the Asia Society Policy Institute’s China climate hub, attended the meetings. He said in a note that China’s decision to bid “reportedly came from [President] Xi Jinping”, galvanising a coordinated cross-ministry effort to secure host the secretariat.
Creating debate
China entering the race has caused a stir.
As host, it could inhibit “robust environmental safeguards” by “embedding elements of its domestic governance model” into how the treaty operates, wrote Dr Chime Youdon, research fellow at India’s National Maritime Foundation, on the organisation’s platform.
But such concerns are weakened by the fact that China would “want the treaty to function” if it were host, argued Prof Philippe Le Billon and Zelda Ladefoged, professor and master’s student at the University of British Columbia, in an article for the Conversation.
Nevertheless, they noted “sustained” worries around China’s influence, given the extensive involvement of its companies in distant-water fishing and deep-sea mining, which are not covered in the treaty.
Li told Carbon Brief that, as far as he saw, no-one was “actively pushing back against” the bid on any of the above grounds. Instead, he observed “anxieties” around “accreditation, information security and visa and conference participation issues”.
Daniel Kachelriess, cross-cutting coordinator at the High Seas Alliance, an umbrella group of non-governmental organisations focused on ocean governance, echoed this in comments to Carbon Brief. He said “values like neutrality and impartiality, transparency and accountability” are important for the decision, as well as practical issues such as “reliable” internet access.
The Financial Times reported that Chinese delegates have offered immunity to attendees and flexibility around visas, citing unnamed sources.
But a successful Chinese bid could be a “significant escalation” of China’s involvement in global environmental governance, wrote Le Billon and Ladefoged.
As such, the BBNJ could prove a “case study” of sustaining environmental progress without the US and of China “learning to translate its ambitions into leadership”, said Li.
Watch, read, listen
PROFIT PRESSURE: The Economic Observer investigated how higher profit remittance requirements for state-owned enterprises is placing pressure on the balance sheets of power, coal and other energy companies.
CARNEY’S CALCULUS: The Wire China Podcast discussed how a deteriorating relationship with the US affected Canada’s approach to importing Chinese electric vehicles.
AFRICAN SOLAR: Climate Home News interviewed a renewables company working in Africa about what the end of Chinese solar export rebates could mean for the continent.
FUEL PRICE WOES: The New York Times published a video about how rising diesel prices are hitting China’s long-haul truck drivers hard.
140%
The year-on-year rise in March in exports of Chinese new-energy vehicles (NEVs, including both plug-in hybrids and pure electric vehicles), reported Bloomberg, citing renewed interest caused by the “global energy shock stemming from the Iran war”.
-14%
The year-on-year fall in March in domestic sales of Chinese NEVs, reported Yicai, citing “changes to the NEV purchase tax exemption and the overlapping effects of the Chinese New Year holiday”.
New science
- Between 1978 and 2023, emissions of “gaseous reactive nitrogen” – including ammonia and nitrous oxide – from croplands in China more than doubled | PNAS
- There are “disparities in [the] energy transition” between households in rural China, with small, low-income households and areas in the Loess plateau facing a “disproportionate energy burden and energy poverty” | Communications Earth and Environment
Recently published on WeChat
China Briefing is written by Anika Patel, with contributions from Lekai Liu, and edited by Simon Evans. Please send tips and feedback to china@carbonbrief.org
The post China Briefing 16 April 2026: Billions for grid | Petrochemical plan | China’s high-seas bid appeared first on Carbon Brief.
China Briefing 16 April 2026: Billions for grid | Petrochemical plan | China’s high-seas bid
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