Petrol Making Plant
© Andrew McFadyen/Al Jazeera
The plant prototype harvests carbon dioxide from the air.
Aberdeen, Scotland- With one of the world's most famous railway lines, Stockton-on-Tees has already given birth to one transport revolution. On September 27, 1825, it carried the first ever passenger rail service along its 40km route through industrial north-east England - changing the world forever.

Today, it is at the centre of another technological breakthrough that some scientists and engineers believe could be just as significant as steam locomotion.

A small company working in two converted shipping containers says it has found a way to make petrol from fresh air and water. Air Fuel Synthesis Chief Executive Peter Harrison says the process could help curb climate change by providing a cleaner alternative to oil.

"We've taken carbon dioxide from air and hydrogen from water and turned these elements into petrol," he told Al Jazeera. "For a country like the UK it means we could create all the fuel you want from renewable energy."

The 58-year-old civil engineer, who used to work in the offshore oil industry, describes it as an amazing project to be involved with.

Harrison explained that they use a 30 foot tower on top of their first container to capture CO2 from the air. The process of separation involves combining the air with sodium hydroxide and passing it through an electrolyser.

A similar method is used to split water into hydrogen and oxygen. The CO2 and hydrogen are then synthesised to make methanol, and eventually petrol.

It cost them around $800,000 to build the plant. Since the mini-refinery was switched on in August, they have made 15 litres of fuel that could be used to power any normal car.

Philippa Oldham, head of transport at the Institution of Mechanical Engineers, is excited at the breakthrough. "The process of making petrol from air is relatively straightforward and really does work," she told Al Jazeera.

"This technology could make driving a conventional petrol car carbon neutral. CO2 is emitted when fuel is used in a car, therefore, for the car to be classed as carbon neutral, CO2 can be captured from the atmosphere and, using simple chemical reactions and electricity, turned back into fuel, where the whole cycle begins again - which means that the net amount of CO2 in the atmosphere remains constant."

Lots of power

Air Fuel Synthesis is now seeking just over $8m to fund a commercial plant they hope would be capable of producing one ton of petrol a day by 2015.

The barrier to expansion is that the process uses lots of power. Much more energy is fed into the plant, in the form of electricity, than is extracted from it.

Because of this, Lee Cronin, professor of chemistry at the University of Glasgow, is cautious about its potential.

"The bottom line - making very optimistic assumptions about their efficiency, if this company was to scale up to produce enough gasoline to meet demand in the USA, it would require half the world's energy consumption every day," he said. "That is clearly unacceptable."

He added that the company had nonetheless developed an interesting new system and discussing it gets us thinking.

If we could take really cheap renewable energy, such as solar power, and produce carbon neutral fuel for cars or aeroplanes, the potential is there to create new revenue streams for desert regions with low populations. It would also enable Gulf states such as Qatar and Saudi Arabia, which have an abundance of sunshine, to diversify their economies.

Keith Allot, chief climate change adviser for WWF, said: "I think it is too early to say how big this could become, but it is certainly interesting and really worth exploring. If we are going to make an impact on climate change, we need to change energy systems at every level."

The UK, and particularly Scotland, is currently investing in lots of wind power. Scotland's renewable energy industry already produces more electricity than either coal or gas and it is growing fast.

Renewable electricity

One problem for policy makers is that the wind changes from day to day and season to season. What do you with the energy that is created when it blows hard outside of peak hours and demand for electricity is low?

Harrison believes Scotland's ambitious targets mean there will be plenty of spare power. "There is a lot of renewable energy around at the moment that is wasted," he said. "What we want to do is to catch all that spare renewable electricity and use it in other forms. Petrol is something that is very useful and easy to store."

Scottish Green Party co-leader Patrick Harvie is more sceptical. He warned that technological advances should not allow people to pretend that nothing else needs to change.

"Even if they can achieve impressive improvements in the overall energy balance in synthetic hydrocarbons, there will still be limits on the amount of renewable energy we can generate, and so there will be a need to reduce demand for energy including from aviation and other transport uses."

At its site in Stockton-on-Tees, Air Fuel Synthesis is demonstrating its clean, green fuel on a small motorised scooter. They believe they have passed a major milestone on the way to carbon neutral motoring that doesn't damage the environment.

Soon, they hope their fuel will be powering Formula One racing cars. Peter Harrison says that, to start with, they are targeting their product at motor sports, which need to improve their green credentials.

Eventually, they hope that petrol produced from water and air could be used in everything from cars doing the school run to local buses and trans-Atlantic jets.

This technology is still in its early stages, but it offers an alluring glimpse of a different kind of future.