Create fuel out of thin air; yes, you read it right. Scientists say they have created a new system that can produce power out of sunlight and air.
The new system is notable because it can work under field conditions rather than specialized and specific needs.
Eventually, it could use it to create carbon-neutral fuels for things like aviation and shipping – but significant amounts of development and upscaling would be required first, the engineers behind the discovery note.
The system is part of a broader attempt to build new processes that could help reduce 8 percent of humanity’s carbon dioxide emissions from flying and shipping. One option is to make new drop-in fuels that would work like the current kerosene or diesel but are created synthetically, out of water and carbon dioxide, and powered by solar energy.
Create fuel out of thin air: Do you think it’s possible
Over the past few years, some scientists have made the seemingly outrageous claim that they could make fuel from thin air. The most recent announcement comes from Cornell University startup Dimensional Energy. In a press release – Add sun: McGovern startup converts CO2 into fuel — Cornell announced:
Dimensional Energy is pioneering artificial photosynthesis to produce green polymers and chemicals. “In industrial uses, we can capture carbon dioxide from commercial entities before it leaks into the atmosphere. Then, we put it into our reactor, added hydrogen, and sunlight. All of this goes into our machine and comes out as a useful fuel,” said David Erickson, a Cornell Atkinson Center fellow.
But here is a sampling of previous researchers making similar claims:
- In 2009, Professor Dobieslaw Nazimek at the University of Maria Curie-Sklodowska in Poland announced an artificial photosynthesis process based on the photocatalytic conversion of water and carbon dioxide into methanol.
- In 2012, a British company called Air Fuel Synthesis made an announcement that they were producing gasoline from thin air. The process combined hydrogen with carbon dioxide to make methanol, and then the methanol was converted into gasoline. It was predicted to be commercialized by 2014. It wasn’t, and the company’s website is now defunct.
- In 2015, Audi announced to great fanfare (e.g., here, here, and here) that it had conjured fuel from thin air using just water and carbon dioxide.
- Perhaps nobody has worked on this concept longer than Harvard’s Daniel Nocera, who summarized the status of the technology in a 2011 paper The Artificial Leaf.
Are these scientists crazy? What’s the real story here?
Engineers Aldo Steinfeld and his colleagues built a working version of the system on the roof of ETH Zürich, the university where they conducted the research. It was made up of three pieces – an air capture unit that takes carbon dioxide and water from the air, a solar unit that captures solar energy and uses it to turn those materials into a mixture of carbon monoxide and oxygen, and another team that turns that gas into liquid so that it could be used as a fuel.
Are they making fool of us?
These approaches are all technically viable. But it’s also technically feasible for me to use this approach to create acetaminophen from thin air. Or just about anything containing the essential ingredients of the atmosphere like carbon, hydrogen, oxygen, and nitrogen. I could even devise a process to create DNA from thin air.
The “catch” in every one of these schemes comes by way of thermodynamic laws. These laws necessarily require that converting water or carbon dioxide back into fuel (like hydrogen) requires more energy inputs than you get back out of the power. For example, to produce 1 British thermal unit (Btu) of hydrogen via electrolysis may require the information of 1.5 Btus of electricity. It may need additional energy inputs to compress, store, and transport the hydrogen.
In short, there’s no free lunch.
The Bottom Line
Such a process could be viable with excess solar power that it might otherwise waste. For example, California has been producing so much excess solar electricity that it pays neighboring states like Arizona to take it. Instead, it might be more economical to convert that excess electricity into hydrogen, which could be stored and later converted back into electricity as needed — even if that means doing so at a net negative energy balance.
The real question with this type of scheme is whether it makes more economic sense to store excess electricity in another form, such as batteries or pumped hydropower. For now, take these “breakthrough announcements” with a grain of salt. Technically viable doesn’t necessarily equate to economically viable, and it isn’t clear which, if any, of these approaches will achieve lasting success.
If they scaled up the system to be large enough, it could potentially satisfy the demand for the much less green kerosene that currently powers the aviation and shipping markets.
But that would need large production plants – roughly 0.5 percent of the Sahara Desert – and the fuel would initially be more expensive than the kerosene.
They note that there would have to be policy support and ways of supporting the initial investment into the fuel.