Scientists are working to develop a reactor which produces fuel using sunlight and carbon dioxide as a widespread way of cutting carbon emissions.

If successful on a commercial scale, the scientists estimate the process could offset up to 700 million tonnes of CO2 each year

The international research team, led by Heriot-Watt University in Edinburgh, will try to increase the efficiency of “photo-catalytic reduction”, a process that uses solar energy to convert carbon dioxide (CO2) into fuels like methane and methanol.

Any carbon produced when the “clean fuel” is used is converted back into energy through a “closed loop” system, the researchers said.

The team have been given a £1.2 million (€1.4 million) grant from the Engineering and Physical Sciences Research Council to carry out the work, in the hope they can increase the photo-catalytic process for wider use.

If is successful on a commercial scale, the scientists estimate the process could offset up to 700 million tonnes of CO2 each year.

Existing photo-catalytic reduction processes do not produce enough fuel to make them financially viable, the university says.

The project will involve developing new, highly efficient photo-reactors, with conversion rates that can be scaled-up to a commercial process.

Mercedes Maroto-Valer, director of the Centre for Innovation in Carbon Capture and Storage, will lead the work in the UK and the team includes engineers and chemists based in Taiwan, the US, Canada and China.