The first flight powered by 100 percent sustainable fuel (SAF) has taken off. On ...
The first flight powered by 100 percent sustainable fuel (SAF) has taken off. On Nov. 28, Virgin Galactic's Boeing 787 flew the transoceanic route from London's Heathrow Airport to New York's John F. Kennedy International Airport, marking a green breakthrough in the aviation industry.
Virgin has obtained a special permit from the U.K. Civil Aviation Authority to fly exclusively on sustainable fuel, making Flight100 a historic flight. Currently in fact, ASTM International allows airlines to use a maximum of 50 percent Saf with conventional kerosene to power their aircraft engines.
SAF stands for aviation fuels that are not produced from fossil fuels and are therefore capable of producing a lower carbon footprint than conventional fuels.
The sustainable fuel used for the first transatlantic flight is composed of waste cooking oils, animal fats and vegetable products. In detail, 88 percent of the mixture consists of Hefa (hydro-processed esters and fatty acids). The vegetable oils in question are collected from a variety of sources, including McDonald's restaurants. SAF can also be derived from other types of waste such as alcohol, municipal solid waste, and sewage sludge.
Environmentally friendly fuel does not require the use of special engines or modifications to aircraft. However, its use is still limited, amounting to 0.1 percent of the total fuel used by airlines partly because of the difficulty of finding it and the cost of three to five times more than regular jet fuel.
However, there has been no shortage of criticism of the first flight powered by sustainable fuel, especially from environmentalists.
The production of SAFs, they argue, leads to the exploitation of land that should instead be used to produce food crops. In fact, a Royal Society Net Zero Aviation Policy report showed that about half of the UK's agricultural land would have to be used to meet the demand for aviation SAF.
"This is not," explains Virgin Atlantic's vice president of business development Holly Boyd-Boland, "a zero-emission flight. It does, however, demonstrate that we have huge levers out there and huge opportunities to materially reduce carbon emissions from flights already."
By completely replacing kerosene, SAF could reduce life-cycle carbon emissions by more than 70 percent compared to conventional fossil fuel. Today, however, we are not yet talking about zero-emission flights, possible perhaps with the use of electric or hydrogen engines, but Flight100 represents a first step toward decarbonizing the aviation industry.
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