The beginning of electric aviation has come, but it will be many years before the average ecologist can fly through no fault with a fully electric long-haul jet.
Meanwhile, scientists are trying to make the commercial aircraft we already have more sustainable, and one of the best ways to do that is to change the fuel they consume.
Instead of spitting out carbon dioxide (CO2) in the atmosphere, researchers at Oxford University and the University of Cambridge in the United Kingdom have proposed a way for planes to capture this gas from the air and burn it with fuel.
Instead of creating an entirely new fleet of electric aircraft, which would require huge leaps in battery storage technology, this new approach would allow the world to reduce its carbon footprint by flying much earlier. That is, if it proves to work on a larger scale.
In the laboratory, researchers were able to capture and convert CO gas2 directly to aircraft fuel using an economical iron-based catalyst.
The amount of liquid fuel produced is still too small to power a real aircraft, but if fossil fuels can be captured from the air at a sufficiently high volume, they can be converted into energy with sufficient efficiency and re-emit , a plane could theoretically be carbon neutral.
“This catalytic process provides an attractive route not only to mitigate carbon dioxide emissions, but also to produce renewable and sustainable aircraft fuel,” the authors write.
“Recycling carbon dioxide as a carbon source for both fuels and high-value chemicals offers considerable potential for both the aerospace and petrochemical industries.”
Typically, when fossil fuel is burned, the hydrocarbons it contains are converted to carbon dioxide and water, releasing energy. The new system essentially reverses this natural process.
By adding heat to the system, engineers were able to combine carbon dioxide with hydrogen, divided from water, to produce a few grams of liquid fuel that, according to the authors, could run on a jet engine.
The catalyst responsible for this impressive chemical reaction consists of iron, manganese and potassium, which are abundant elements on Earth, easier and cheaper to prepare than many similar candidates. The catalyst also combines easily with hydrogen and shows high selectivity for a range of jet fuel hydrocarbons.
The result is some fuel, as well as various petrochemicals that can only be obtained from fossil fuels.
The new system will not be the first nor will it be the last to make our carbon emissions a desirable biofuel. In Canada, scientists have developed a huge industrial complex to capture CO2 as trees in a forest would do, using it to form hydrocarbon fuel.
But even a handful of studies have shown that it is possible to convert atmospheric CO2 in liquid fuel, it is extremely difficult and expensive to produce more than a small amount.
The new system looks promising, but whether or not its practice is anything else.
“This looks different and it looks like it could work,” said Joshua Heyne, an independent engineer who was not involved in the study. With cable.
“Enlargement is always a problem and there are new surprises when it comes to a larger scale. But in terms of a longer-term solution, the idea of a circular carbon economy is certainly something that it could be the future. “
Some, like Heyne, have hope, while others see “flying on the air” like a simple hype. Last year, when a European company announced it was working on a way to capture CO2 from air to powering future aircraft, critics noted that the fuel produced each day would only allow for five minutes of flight.
Such low yields are not a solution to the climate crisis and some environmentalists argue that our only feasible option is to fly less. Especially because the reality of a circular carbon economy is still a long way off and the climate change crisis is already looming.
In the end, it all depends on how quickly we can expand this promising technology, and in fact, it may not happen fast enough.
Engineers want to connect their new system to established carbon emitters, such as coal-fired power plants, and this, of course, would require continued production of fossil fuels. It is also very expensive and may not be attractive to companies even if it works.
However, with the acceleration of climate change and aviation will only increase in the coming years, the team of engineers argues that CO2 conversion and use as an “integral and important part of greenhouse gas control and sustainable development.”
Other sustainable plant-dependent biofuels require large amounts of farmland and do not address our emissions at the same time.
“This is, therefore, the vision of the route to achieve net carbon emissions from aviation,” they conclude, “a culmination of a future global zero-carbon aviation sector.”
We will see.
The study was published in Communications on Nature.