Stockholm wants to make electric cars a power source in times of crisis

- These are batteries that roll around in our streets and we can use them in the electricity grid, says Åsa Lindhagen (MP), environmental and climate councilor in the city of Stockholm and elected Member of Parliament.

A preliminary study by Sweco, which was carried out on behalf of the environmental administration, shows that the city of Stockholm's electric vehicle fleet has a large, untapped potential as an energy resource. By using bidirectional charging – where the electric cars can not only be charged but also send electricity back to buildings or to the grid – the city can move from being a mere electricity consumer to becoming an active part of the energy system.

Today, roughly every fourth electric car in the Stockholm city fleet is compatible for V2G, that is Vehicle to grid as the technology is called. If the entire electric fleet was utilized, it could store energy equivalent to the daily consumption of 700 villas or generate an effect comparable to 2.5 wind turbines, Sweco's report shows.

According to the report, the city's driving patterns are also favorable for the technology. The vehicles are often parked and plugged in for long periods. According to Sweco, this creates good conditions for using the cars as battery storage without affecting daily operations.

The report also shows that the city can lower its charging costs by as much as 36 percent by controlling the charging at times when the electricity price is low. Bidirectional charging also opens up the possibility of selling electricity and support services to the electricity grid, which could generate large revenues.

- These are resources that we already have, so now it's about using them in a smarter way. If we do it the right way, we can both reduce costs and bring in new revenue, says Åsa Lindhagen.

The report also highlights the preparedness aspect as one of the stronger reasons to use the technology. The cars would, for example in the event of a power cut, be able to secure the operation of security points and socially important operations.

- What happens if we have a power outage at a nursing home, for example? Then these cars can be an incredibly important part from a preparedness perspective, explains Åsa Lindhagen.

In order to realize the potential, the city now requires V2G compatibility when purchasing vehicles in the future. The next step is to go from theory to practice.

- We want to start this by setting a task to run a pilot project, says Åsa Lindhagen.