Novel catalysts for producing sustainable aviation fuel and more

The new technology platform fully integrates with partner technologies to create truly carbon-neutral fuels

Spotted: Aviation is one of the toughest sectors to decarbonise. While promising efforts are well underway to power planes using batteries, hydrogen fuel cells, and liquid hydrogen, these are focused on shorter flights. Long-haul flights remain a tougher nut to crack.

Today, batteries lack the energy density to power heavier aircrafts, and while some hope that next-generation solid-state batteries might provide the answer, the technology isn’t currently there for electric long haul. Similarly, the power density of hydrogen fuel cells is too low for long flights of heavy aircraft, and gas and liquid hydrogen, while light, take up much more space on an aircraft than jet fuel and must be compressed, requiring tanks that are too large and heavy for longer flights.

Sustainable aviation fuels (SAFs) are an alternative solution that many are pinning their long-haul hopes on. SAFs are fuels that have similar chemistry and behave in a similar way to traditional jet fuel. They can be ‘dropped in’ to existing planes, which is why they are often also called ‘drop in’ fuels. SAFs can be made from bio-based materials – indeed, commercial flights powered by biofuel have already taken place – but there are significant concerns about the availability of feedstock for this approach. US startup Dimensional Energy, on the other hand, is one of several companies looking at producing SAF using captured CO2 as a feedstock.

Chemically, SAFs are made up of hydrogen and carbon atoms, just like kerosene. But in the case of Dimensional’s process, the carbon ultimately comes from CO2 captured from industrial sources, combined with green hydrogen produced using an electrolyser powered by renewable electricity. The company’s core breakthrough is the development of novel catalysts that break the ‘notoriously stable’ molecular bonds within carbon dioxide releasing one of the oxygen atoms to create carbon monoxide. This carbon monoxide is then combined with hydrogen to create syngas, which can be further transformed into jet fuel.  

Dimensional’s process is powered by renewable energy, and because the fuel is made using captured carbon, it only emits CO2 that would have been emitted by the industrial source. However, to be truly ‘carbon-neutral’ the fuel would need to be made from CO2 captured from the atmosphere, and the startup states that its system can integrate with direct air capture – a technology that can do this – as it matures.

The main limitation for SAF today is scalability, so the ability to ramp-up production is crucial for startups operating in this space. Dimensional is currently producing, around 5 gallons of its fuel today at its demonstration plant in Tucson, Arizona. This is a very small amount, but the company has long-term plans to open larger plants in Vancouver (2023), Niagara Falls (2025), and California (2027), and is also exploring licensing partnerships with other fuel manufacturers.

Springwise has previously spotted other SAF innovations such as a partnership between a German aircraft manufacturer and a South African energy company and a project in Chile to produce SAF using wind power.  

Written By: Matthew Hempstead