SAF-e flight

The first transatlantic flights with 100% sustainable aviation fuel

Hey there,

Today, we’re taking a look at sustainable aviation fuels (SAFs) and aviation in general, as it will allow us to neatly weave a number of financing rounds and other news into one story. After that, as always, keep reading for a roundup of climate tech and energy deals and headlines. 

In today’s email:

  • SAF-e flight: Transatlantic flights with sustainable aviation fuel

  • Climate tech fundraising announcements 

  • Climate tech and energy headlines


It's been a busy few weeks for more sustainable aviation. Two different transatlantic flights were completed in the past two weeks using 100% 'sustainable aviation fuel.' The first, last week, marked the world's first trans-Atlantic flight to log the 100% sustainable aviation milestone. The flight was completed in a Gulfstream G600 aircraft, more private jet than major airliner. This week, however, a much larger aircraft, a Boeing 787, achieved a 100%-SAF flight from London to New York

These milestones took me by surprise. My (admittedly uninformed) guess at when we'd see 6-7 hour flights completed on 100% SAF three weeks ago would have been 2025. So there's good news here: Decarbonization steps are happening faster than expected. That said, there's a lot more worth exploring. How impactful is SAF really? How much of aviation's impact on the climate comes from fuel? How much should we care about aviation in general?

A Boeing 777-200 ‘ecoDemonstrator’ takes off for a demonstration of sustainable aviation fuel-powered flight at an airshow in Oshkosh, WS, in 2022 (Shutterstock)

Start your engines

Jet fuel is pretty different from the gasoline in your car. It has a much higher energy density. Said differently, it provides more energy per unit volume. High energy density fuels are essential for planes as they allow them to carry sufficient fuel for long-distance flights. Jet A is a kerosene-based fuel derived from crude oil through a refining process. Batteries can replace the internal combustion engine in your car, but they won't work for big planes.

Creating viable alternatives to jet fuel is no small feat. SAFs are expressly designed to mimic conventional jet fuels in terms of their chemical and physical properties to make them compatible with existing engines and infrastructure. Like many jet fuels, SAFs are hydrocarbons and are designed to have a similar chemical structure to jet fuels, down to similarities in their carbon chain length to ensure similar energy content and combustion characteristics. The same goes for freezing points and viscosities; these need to be similar, too, lest SAFs lead to operational issues at high altitudes and low temperatures. SAFs can also be blended with traditional jet fuels in various proportions, like hydrogen can be co-fired alongside natural gas or coal in power plants. 

In terms of production, SAFs can be produced from a vast slew of feedstocks, ranging from biomass to waste oils and other resources, like waste CO2. The Virgin Atlantic-operated Boeing 787 that flew 'over the pond' this week leveraged 88% waste fats and 12% synthetic aromatic kerosene made from plant sugars. Also this week, Infinium, a Sacramento-based eFuels company, announced it has raised $75M in project equity financing from Breakthrough Energy Catalyst for its 'Project Roadrunner.' Infinium aims to develop Project Roadrunner into one of the world's largest sustainable aviation fuel production facilities. Specifically, the plant will convert waste CO2 into SAF via renewable energy.

Doubling down on the CO2 piece for a minute, the waste-to-value opportunity is another big piece of the appeal in the SAF story. Many companies, like Infinium, are working to valorize captured or wasted CO2 and turn it into SAF. While CO2 isn't as valuable as other greenhouse gasses, like methane, which is packed with energy, the market for carbon 'utilization' is growing as carbon capture and removal companies 'produce' more CO2. 

Rather than always focusing on how to permanently sequester carbon, trying to find uses for it makes sense. SAF is a leading pathway to increase demand for carbon utilization. And the story is elegant; using waste CO2 to reduce future CO2 emissions from aviation offers a compelling, circular, 'complete' narrative. At least if you're purely focused on CO2. As we'll now explore, unfortunately, CO2 isn't where the buck stops for aviation.

Note: There are other approaches to decarbonizing air travel beyond SAF. Also this week, ZeroAvia, a Hollister, CA-based company building hydrogen-powered aviation technologies, announced a $116M Series C funding round. Whether for heavy-duty trucking or planes, hydrogen can offer a large amount of energy per unit of weight. The challenge with hydrogen is that it has a much lower energy density on a volume basis. That's why several companies that want to use hydrogen for transportation use ammonia as a hydrogen 'carrier;' ammonia (NH3) allows you to 'store' more hydrogen on a volume basis, though it does mean you also need a 'cracking' technology to separate hydrogen from nitrogen onboard, too.

100% SAF <> 100% clean

To say nothing of how long it will take for the entire airline industry to adopt SAF, another part of the challenge inherent to making aviation ‘less bad’ is that CO2 emissions from burning jet fuel represent, by some estimates, less than half of aviation’s impact on climate change and global warming. The combustion of jet fuels (and SAF) in jet engines also produces other warming agents including nitrogen oxides, as well as water vapor. While water vapor is a less conspicuous climate change culprit than carbon dioxide or nitrogen oxide emissions, it can contribute to the formation of contrails and cirrus clouds, which have a warming effect on the atmosphere. Specifically, contrails can trap outgoing longwave radiation, leading to a localized warming effect. 

While aviation represents about 1.9% of global greenhouse gas emissions, when you take other factors such as contrails into account, estimates of aviation’s impact on global warming come in much higher (3.5%). How significant a contributor to global warming the non-CO2 emissions and non-emissions-based impacts of aviation are on climate change is an active field of research.

Global warming drivers like water vapor and contrails are also theoretically easier to mitigate with things like route changes and flying at different altitudes. Still, I hope it’s some interesting fuel for thought. My broader point is that 100% SAF flights aren’t 100% ‘clean.’ Like most climate technologies, they’re a stepwise improvement. One we can still celebrate while staying clear-eyed about the full scope of aviation’s climate impacts.

The net-net (tl;dr)

From a 30,000-foot view, a few things are true for me in the SAF story:

  • Good news: Decarbonization is happening, often faster than I and others expected.

  • The nuance: The word de-‘carbon’-ization itself notably omits mention of the many other components of aviation that drive global warming.

  • Zooming out even ‘higher’: Addressing the impact of sectors like aviation is ‘overweighted’ by policymakers, investors, and general resource allocation. Reducing the impact of aviation is important. But I’d argue that plugging methane leaks in oil and gas infrastructure, for example, will mitigate more global warming out to 2050 and should be more achievable. More on this later in the email.

I think we often focus on aviation because it’s a readily appreciable example. Most of us go on planes. We see them in the sky. We know it’s an emissions-intensive enterprise. We love to lambast rich folks in private jets, including the irony-immune ones who flew private to COP 28.

Still, the aviation example itself attunes us to the fact that addressing global warming is about much more than addressing carbon dioxide emissions. ‘Decarbonization,’ even as the word has become a stand-in for efforts to address climate change in general, represents half, maybe less, of the systems overhaul that needs to happen this century to address climate change. All other components of the climate conversation often feel underserved to me. I’ll spend more time on this beat in 2024.


Large funding rounds

🌞 mylight150, based out of Lyon, France, raised ~$109M in equity financing to make ‘smart’ solar panels and batteries. Eiffel Investment Group, Azora Capital, and Andera Partners co-led. More here. (France, Energy)

💦 ZeroAvia, based out of Hollister, CA, raised $116M in Series C funding for its hydrogen-powered aviation technologies. Airbus, Barclays, UK Infrastructure Bank, and others invested. More here (paywall). (U.S., Transportation)

📊 Braincube, based out of Versailles, France, raised $91.1M in equity funding for its IoT and software tools designed to help manufacturers enhance factory-level efficiency, quality, and sustainability. Scottish Equity Partners and Bpifrance co-led. More here. (France, Industry)

Medium-sized funding rounds

⛏️  Adionics, based out of Les Ulis, France, raised $27M in Series B funding for its ‘liquid-liquid’ direct lithium extraction process. SQM, Bpifrance, Supernova Invest, and others invested. More here. (France, Industry)

👷 Kahuna Workforce Solutions, based out of Houston, raised $21M in Series B funding for its skills management and training software targeted at workers in industries like energy and manufacturing. Resolve Growth Partners led. More here. (U.S., Energy)

🚲 HumanForest, based out of London, raised ~$21M in Series A funding for its e-bike sharing network. Triodos Bank UK led. More here. (U.K., Transportation) 

🚲 EMotorad, based out of Pune, India, raised $20M in Series B funding for its e-bike marketplace. Panthera Growth Partners led. More here. (India, Transportation)

🔩 Immensa, based out of the United Arab Emirates, raised $20M in Series B funding for its additive manufacturing solutions targeted at the energy sector. Global Ventures led. More here. (UAE, Industry)

⬇️ Carbo Culture, based out of Helsinki, Finland, raised $18M in Series A funding to commercialize its “industrial-scale biochar carbon removal” technology. GenZero and True Ventures co-led. More here. (Finland, Carbon Removal)

📊 Modo Energy, based out of London, raised $15M in Series A funding for its software that offers data analytics on utility-scale battery energy storage and other renewable energy assets. MMC Ventures led. More here. (U.K., Energy)

🚗 GoMetro, based out of Cape Town, South Africa, raised $11.4M in Series A funding for its fleet management and optimization software. Zenobē Energy led. More here. (South Africa, Transportation)

🦠 Again, based out of Copenhagen, Denmark, raised $10M in seed funding to use bacteria to convert CO2 into base chemicals for other products. Again is operating a first-of-a-kind biomanufacturing site that can turn 1 ton of CO2 per day into chemicals. Acme, GV, and Atlantic Labs invested. More here. (Denmark, Industry)

Smaller funding rounds

♨️ Hyme, based out of Copenhagen, Denmark, raised ~$8.8M in equity funding for its energy storage technology that heats liquid salt with electricity. The heated liquid salt can then be stored in a hot tank for up to two weeks, with a daily power loss rate of ~1%. To discharge the energy, the hot salt is converted into steam for direct use in industrial processes or to power a turbine to generate electricity. Existing investors Heartland A/S, Nordic Makers, and North-East Venture participated. More here. (Denmark, Energy)

📊 Vesper, based out of Amsterdam, raised ~$5.5M in Series A funding for its agricultural commodity intelligence platform. Keen Venture Partners and Piton Capital led. More here. (Netherlands, Food & Agriculture)

📊 Climate Alpha, based out of Singapore, raised $5M in seed funding to provide real estate, asset managers, and insurance companies software to help predict climate volatility. Jungle Ventures led. More here. (Singapore, Climate Data Management)

SparkMeter, based out of Washington, D.C., raised $5M from Honeywell Smart Energy for its ‘Advanced Meter Infrastructure’ business, as part of which it offers grid management services, equipment, and grid management-focused software solutions. The company works across Africa, Asia, and North America. More here. (U.S., Energy)

🔌 Monterra, based out of San Francisco, raised $2.5M in pre-seed funding for its software that automates the design and planning of EV charging installations. Base10 Partners led. More here. (U.S., Transportation)

📊 BeCause, based out of Copenhagen, raised $1.9M in seed funding for its sustainability data management software targeted at the hospitality, travel, and tourism sectors. Ugly Duckling Ventures,, and Mercato invested. More here. (Denmark, Climate Data Management)

📊 Envirly, based out of Lublin, Poland, raised ~$1.55M in seed funding for its B2B SaaS product that helps companies manage carbon emissions and ESG reporting. Bank BNP Paribas, Tangent Line Ventures, Aligo VC, and others participated. More here (paywall). (Poland, Climate Data Management)

🔋 Floatech, based out of Madrid, raised ~$1.3M in funding for its silicon anodes and nanomaterial technologies. GROW Venture Partners led. More here (en español). (Spain, Industry)

🔋 Malta, based out of Cambridge, MA, raised an undisclosed amount of funding for its ‘thermo-electric’ long-duration energy storage technologies. Siemens Energy Ventures and Alfa Laval invested, as did existing investors. More here. (U.S., Energy)

Other funding rounds

In private equity: 

🏗️ One Click LCA, based out of Helsinki, Finland, raised ~$44M from PSG Equity and InfraVia Capital Partners for its building life-cycle carbon emissions assessment software. More here. (Finland, Built Environment)

Xlinks, based out of London, raised ~$25M from Total Energies to develop a massive renewable energy project in Morocco that will combine solar, wind, and energy storage to supply electricity to the U.K. via high-voltage direct current subsea cables. More here. (U.K., Energy)

In acquisitions:

Ardian, a private equity firm based out of Paris, is buying Verne Global, a London-based low-carbon data center company, from Digital 9 Infrastructure for up to $575M. Verne Global operates five renewable energy-powered data centers in London, Iceland, and Finland. More here. (U.K., Industry)

👷 Climate Draft, a U.S.-based climate job posting site, was acquired by Lowercarbon Capital. Terms weren’t disclosed; Lowercarbon Capital had previously invested in the business. More here. (U.S., Climate Jobs)

In project equity and debt financing:

🌞 S.B. Energy Global, based out of Redwood City, CA (where I was born), raised $2.4B in financing for four utility-scale solar projects in Texas. J.P. Morgan, Bank of America, Morgan Stanley Renewables, and Truist Bank provided ~$800M in tax equity, while seven other financial institutions added $450M in term debt and $1.2B in construction-linked debt. More here. (U.S., Energy) 

🌞 Excelsior Energy Capital, based out of Excelsior, MN, raised $1.3B in debt financing for its Faraday Solar project, which is a 682.5 MW ground-mounted solar facility in Utah County, UT. Excelsior acquired the project from its original developers, Parasol and Clenera, earlier this year. More here. (U.S., Energy)

💸 Breakthrough Energy Catalyst, the European Commission, and the European Investment Bank announced public / private financing commitments for Fredericia, Denmark-based Ørsted’s ‘FlagshipONE project,’ Europe’s largest e-Methanol project, and Milan, Italy-based Energy Dome’s ‘Ottana Project,’ a long duration energy storage project leveraging Energy Dome’s CO2 Battery technology. Together, the investment partnership aims to unlock ~$915M in public and private funds. More here. (Europe, Energy / Industry)

Longroad Energy, based out of Boston, MA, raised $600M in debt financing to expand its portfolio of renewable energy projects in the U.S. More here (paywall). (U.S., Energy)

🌞 Primergy Solar, based out of Oakland, CA, raised $300M in debt financing and tax equity investment to develop a 100 MW solar project in Ashley County, AR. More here. (U.S., Energy)

🔁 Infinium, based out of Sacramento, CA, raised $75M in project equity financing from Breakthrough Energy Catalyst (also active two bullets above) for its ‘Project Roadrunner,’ which aims to become one of the world’s largest sustainable aviation fuel production facilities. Infinium’s plant will convert waste CO2 into SAF via renewable energy. More here. (U.S., Transportation)

🧪 Liberation Labs, based out of Richmond, IN, received a $25M loan backed by the U.S. Department of Agriculture to build a precision fermentation facility. More here. (U.S., Synthetic Biology) 

In grant funding:

🏠 Marin Clean Energy, based out of San Rafael, CA, received $158M in grant funding from the California Public Utilities Commission to help 3,600 low and middle-income households make electric upgrades to their homes. More here. (U.S., Built Environment)

⚛️ The Saskatchewan Research Council, based out of Saskatoon, Canada, raised $80M in grant funding from Saskatchewan’s government to explore deploying a Westinghouse Electric eVinci™ 5MWe nuclear microreactor in its province. More here. (Canada, Energy)

🍣 The Canadian government invested $11.4M in three Canadian businesses, New School Foods, a plant-based seafood company, Liven Proteins, a precision fermentation startup, and NuWave Research, a provider of dehydration solutions, to commercialize a whole-cut ‘vegan’ salmon alternative. More here. (Canada, Food & Agriculture)

New funds

💵 Antin Infrastructure Partners, a Paris-based private equity firm, raised ~$1.3B for a sustainable infrastructure fund. More here. (France, Funds)

💵 LeapFrog Investments, based out of London, raised $500M from Temasek and the European Investment Bank for its climate-focused investment strategy that’s focused on Africa and Asia. More here. (U.K., Funds)

💵 Invest-NL and the European Investment Fund jointly launched the Dutch Future Fund II with ~$220M to invest in other Dutch venture funds that focus on the energy transition, circular economy, deep tech, agriculture, and food startups. More here. (Netherlands, Funds) 

💸 Bethnal Green Ventures, based out of London, raised !$41.5M for an early-stage fund focused on sustainability. The company also notes it aims to allocate at least half its new fund to woman-founded startups. More here. (U.K., Funds)

💸 Resolve Ventures, based out of Dublin, Ireland, raised ~$33m for a new growth capital focused on Irish startups with significant potential climate impact. More here. (Ireland, Funds)

🥝 Zespri, based out of Mount Maunganui, New Zealand, launched a $2M fund to make its kiwi supply chain more sustainable. More here (paywall). (New Zealand, Food & Agriculture)


🔋 Onshoring: Nissan plans to invest ~$2.5B to build two new EVs and another battery manufacturing plant in Sunderland, England, where it already has a manufacturing presence. 

Elsewhere, REC Silicon restarted a polysilicon factory in Moses Lake, WA, that had sat idle for five years. The company plans to sell its polysilicon to Hanwha Solutions, which will use the polysilicon at its Qcells solar ingot, wafer, cell, and panel factory. While production has started at Hanwha's plant in Georgia, it's still under construction; the company aims to ramp production in 'late 2024.'

⛏️ Groundbreaking: Sila held a ribbon-cutting ceremony (paywall) at its silicon anode and EV battery manufacturing plant that’s also in Moses Lake, WA (see above re: REC Silicon), this week. When finalized (~2025), the company aims for the factory to produce sufficient silicon anode material for 1M EV batteries annually.

✈️ SAF-e flight: Last week, the world's first trans-Atlantic flight to use 100% sustainable aviation fuel was completed in a Gulfstream G600 aircraft. This week, a much larger airplane, a Boeing 787, achieved a 100%-SAF-powered flight from London to New York. The Virgin Atlantic-operated plane burned 88% waste fats and 12% synthetic aromatic kerosene made from plant sugars.

♨️ Breaking through: America's flagship enhanced geothermal power plant, operated by Fervo Energy, produced low-carbon electricity and sent it to the grid for the first time this week in Nevada. Google is the primary financial sponsor for the project, as enhanced geothermal energy could be an attractive power source for its data centers in the future. The 3.5 MW project, Project Red, is supplying power directly to NV Energy, the local utility, for now.

🔌 Innovation: Electreon, an Israeli startup, unveiled its wireless EV charging technology in the U.S. for the first time this week. A quarter-mile section of road in Detroit can now wirelessly charge EVs (provided they're equipped with the appropriate receivers) by transferring electricity wirelessly through a magnetic field.

💵 Public funding: At COP28, UAE, the host nation for this year's conferences, announced it will invest $30B into a new fund focused on low-carbon energy as well as energy transition projects in emerging and developing markets. The UAE aims for the 'Alterra' fund to grow to $250B by 2030. 

Also at COP28, a number of countries announced they will support a new ‘loss and damage’ fund to aid countries most directly and immediately affected by climate change. The UAE and Germany will contribute $100M, the U.K. came in for $50M, the U.S. added $17.5M, and Japan added $10M.

📢 Also at COP 28: 116 countries signed a pledge to triple renewable energy generation capacity by 2050 while 22 countries signed a pledge to triple nuclear energy generation capacity by 2050.

💸 Private funding commitments: Private sector players are making big announcements and funding commitments during COP week, too. IFM Investors, based out of Australia, noted it will invest ~$12.5B in infrastructure and energy transition projects in the U.K. by 2027. Elsewhere, RWE, a German multinational energy company, made a mammoth commitment to invest ~$61B in 'green technologies' between 2024 and 2030. Further, The Rockefeller Foundation, based out of New York, also announced it aims to make its $6B endowment 'net-zero' by 2050

📜 Federal funding: The DOE announced $275M for seven projects that will strengthen climate tech and energy tech supply chains domestically and accelerate domestic manufacturing. For instance, one funding recipient is Carter Wind Turbines, LLC, a family-owned business that will build a new plant in Vernon, TX, to produce mid-sized wind turbines.

⬇️ Christmas for carbon removal purchases: American Airlines inked a new carbon removal offtake agreement with Graphyte, a carbon removal company that has developed a 'carbon-casting' process, i.e., burying waste biomass in a permanent way to sequester carbon underground. American Airlines paid for 10,000 tonnes of removal. While the price point wasn't disclosed, Graphyte advertises it can remove carbon for close to or less than $100 per tonne. 

Elsewhere, Respira purchased 50,000 tonnes of carbon removal from Capture6, a direct air capture company. Capture6 also notes its technology pairs well with other infrastructure; for instance, it claims it can recover 50%+ of freshwater from desalination waste brine.

🚫 so good news: Veev, a Hayward, CA-based modular construction technology company that raised ~$600M, is purportedly close to going out of business. Elsewhere, Our Next Energy, a Detroit-based battery manufacturer, is laying off 25% of its staff. Lion Electric, a Montreal-based manufacturer of medium and heavy-duty urban vehicles, is laying off ~10% of its workforce.

🌞 Closing on good news: The EPA released a final rule designed to reduce methane emissions from oil and natural gas operations. The U.S. is part of a Global Methane Pledge to cut methane emissions by 30% by 2030 from 2020 levels. I’m not holding my breath on the latter, but the former is a step in the right direction. I’ll cover this more in coming weeks.

See you soon,

– Nick

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