In future, up to one million cars in Switzerland could be powered by methane produced using power-to-gas processes. This is one of the conclusions of a white paper that researchers from the Swiss Federal Laboratories for Materials Science and Technology (Empa), the Paul Scherrer Institute (PSI), and other research institutes submitted to the Swiss Federal Energy Research Commission (CORE).

In this paper, the scientists investigated the potential in Switzerland to convert surplus electricity from renewable sources into chemical energy carriers, such as hydrogen, methane, or liquid hydrocarbons.

“The carbon dioxide emissions of these one million cars would be reduced by 70 to 90 percent compared to cars powered using conventional fuels,” says Christian Bach from Empa and co-author of the white paper. Because during the production of methane using power-to-gas processes, the same amount of carbon dioxide is extracted from the atmosphere as is subsequently emitted during combustion.

However, power-to-X technologies can not only reduce the carbon footprint, but also reduce Switzerland’s dependency on energy imports, says Markus Friedl from the Rapperswil University of Applied Sciences, who was also a contributor to the white paper.

The core idea behind power-to-X is to use surplus electricity generated using renewable sources – specifically in the summer half-year – to produce other energy carriers. These, in turn, could be used to generate electricity when there is a shortfall in electricity from renewable sources, especially at night and during the winter months.