The Chicago to Washington DC flight was powered using a fuel made from cooking oil mixed with compounds from plants
Spotted: Aviation is a thorny topic for sustainability. Terrestrial modes of transport may be making progress in moving away from fossil fuels. But the technical challenges that must be overcome if commercial flight is to make the same transition are large. And all the while, aviation contributes around 2 per cent of the world’s carbon emissions – a proportion that seems small but is nonetheless very significant.
The potential paths to de-carbonised aviation can be broadly split into three camps: electrification, airships, and alternative fuels. Each route faces difficult roadblocks, but the alternative fuel option, at least, has just passed an important milestone. United Airlines recently ran a flight carrying 100 passengers that was completely powered by sustainable fuel.
Developed by World Energy and Virent Inc., the fuel is composed of a combination of cooking oil and fat mixed with synthetic compounds derived from plants including beets, corn, and sugar cane. The plane carried 500 gallons of this cooking-oil-based fuel in one engine, and 500 gallons of conventional fuel in the other. The latter was not used, being there only as a back-up.
Using the sustainable fuel instead of normal kerosene results in a carbon emissions reduction of 80 per cent. Previous flights have used a mixture of traditional and sustainable fuel, but the recent flight was the first time only the sustainable fuel was used – an important demonstration of its reliability.
Written by: Matthew Hempstead