A French firm is hoping to sell jet fuel made from sugar beet pulp in a step towards reducing CO2 emissions from commercial aircraft.
Most jets burn huge amounts of kerosene, with large twin-engined aircraft frequently using four litres per second of flight.
The sustainable aviation fuel, made by fermenting the sugar beet pulp, will replace up to 50% of mineral oil-based kerosene, although only up to 3% to begin with.
Marc Delcourt, managing director of Global Bioenergies, which perfected the method, said: “It is not possible to replace more than 50% because of the specifications that are laid down for jet fuel.
“There are aromatics, for example, in kerosene, which engine manufacturers say are essential for keeping some seals lubricated, and they have no interest in designing new engines to get around the problems because to do so will cost billions of euros.
“To be commercially viable, the fuel will have to be able to be used by all the old jets out there too.”
Jet fuel is the second, longer-term product on which Global Bioenergies has based its business plan.
The first money-spinner is in cosmetics. The chemical isobutene, obtained by the firm’s patented process of fermenting sugar beet pulp and the base for its sustainable aviation fuel, is also highly sought-after as a ‘dry oil’ in long-lasting cosmetics.
L’Oréal has taken a majority stake in Global Bioenergies to ensure it has a supply of the company’s isobutene for a range of bio-cosmetics, with the brand ‘Last’ being set up specifically to market them.
“It is a good high-value product, but our process can be scaled up and the bulk market in future will be to provide isobutene for jet fuel.”
One factory is already in the process of being built in France, and it will initially produce 100 tonnes of isobutene a year.
There are plans to build a 2,000 tonne-a-year factory by 2025, and another 30,000-tonne one by the end of the decade. They will be situated next to sugar beet refineries.
Even with bulk supplies, sustainable aviation fuels (SAF) will be up to three times more expensive than fossil fuel ones.
“Some airlines have said they will use as much SAF as possible to reduce their carbon footprint,” said Mr Delcourt.
“And some countries, notably France, Denmark and Sweden, now require all jet fuel sold to have at least 1% of SAF in it, which will probably rise to 3%.
“However, unless kerosene starts to be taxed [jet fuel is not currently taxed at all under an international agreement negotiated in the 1940s, which has not been challenged], or countries insist jet fuel has more SAF in it, the carbon footprint of jet travel will not change.”
Most paperwork for the Global Bioenergies fuel has already been done, and the product has been tested extensively by all the main engine manufacturers, as well as Boeing and Airbus.
The company even flew a small, turboprop aerobatics plane from Germany to France using its fuel in a demonstration flight.
Mr Delcourt said Global Bioenergies is well placed to be the main supplier of sustainable aviation fuel for jets.
“We have rivals who mainly use recycled cooking oil, who are limited by their ability to collect cooking oil and by people eating chips.
“In contrast, our process, based on sugar beet pulp, can also be used with wheat straw or wood chips.”