Engineers at Air Fuel Synthesis (AFS.L) in Teeside, northern England, say they have produced 5 litres of synthetic petrol over a period of three months.

The technique involves extracting carbon dioxide from air and hydrogen from water, and combining them in a reactor with a catalyst to make methanol. The methanol is then converted into petrol.

By using renewable energy to power the process, it is possible to create carbon-neutral fuel that can be used in an identical way to standard petrol, scientists behind the technology say.

"It's actually cleaner because it's synthetic," Peter Harrison, chief executive officer of AFS, said in an interview.

"You just make what you need to make in terms of the contents of it, so it doesn't contain what might be seen as pollutants, like sulphur," he said.

The work is part of a two-year project that has so far cost around 1 million pounds.

The green petrol will not appear on forecourts any time soon, though.

"We can't make (the petrol) at pump prices, but we will do eventually," Harrison said. "All we need is renewable energy to make it, and so when oil becomes a problem we will be able to make a contribution to keep cars moving or to keep aeroplanes moving."

AFS said it was confident the technology could be scaled up to refinery size in the future. Each of the processes that go into making the fuel already take place separately on an industrial scale.

For now, however, AFS plans to build a commercial plant in the next two years that will produce around 1,200 litres a day of specialist fuels for the motorsports sector, Harrison said. (Reporting by Alice Baghdjian; Editing by Chris Wickham and Jane Baird)

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