Decarbonising aviation is possible
Research published in the journal Nature Sustainability shows a pathway toward full decarbonisation of US aviation fuel use by substituting conventional jet fuel with sustainably produced biofuels.
Who among us has not felt at least a twinge of guilt in booking a flight to a far-flung dive destination, knowing very well that the trip will add a significant contribution of CO2 and other greenhouse gases to the atmosphere? Being both a keen traveller and avid environmentalist, I surely have felt conflicted.
Dive travel is a luxury and not a necessity, so are we not a bunch of hypocrites when we try to stand for the environment yet fly long-distance just for leisure?
Surely, we can buy off our indulgences by paying an extra voluntary fee for "bio-sustainable fuel" or some other carbon-offsetting scheme (sometimes of questionable quality or efficacy).
But perhaps there is now hope on the horizon. At least, a new study shows full decarbonisation of US aviation sector is within our grasp, and, I suppose, by extension, ultimately the whole world's too.
The study, led by a team of Arizona State University researchers, found that planting the grass miscanthus, also known as silvergrass, on 23.2 million hectares of existing marginal agricultural lands—land that often lays fallow or is poor in soil quality—across the United States would provide enough biomass feedstock to meet the liquid fuel demands of the US aviation sector fully from biofuels, an amount expected to reach 30 billion gallons a year by 2040.
Hydrogen has long been touted as a sustainable alternative to traditional jet fuel, either as a combustible fuel or used to generate electricity via fuel cells.
The European aircraft manufacturer Airbus is currently developing a hydrogen-powered fuel cell engine—and it plans to test it on the largest commercial airplane ever to take to the skies. The plane builder has previously revealed concept designs for an aircraft utilising liquid hydrogen fuel and combustion engines, but has also suggested fuel cells alone might be sufficient to power smaller commercial aircraft.
The engine uses fuel cells to convert the hydrogen into electricity, which then powers a propeller. "At scale, and if the technology targets were achieved, fuel cell engines may be able to power a 100-passenger aircraft with a range of approximately 1,000 nautical miles," said Airbus' vice president of Zero-Emission Aircraft Glenn Llewellyn.