Storing renewable energy in electric vehicle batteries (EVs) instead of stationary energy storage facilities could help the European Union save more than €100bn over 10 years, according to a European Federation for Transport and Environment (T&E) study.

If the intricacies are worked out, EVs could become the fourth-largest electricity supplier in the EU by 2040. 

To meet their net zero goals, countries in the EU are busy scaling up renewable energy infrastructure using solar panels and wind energy systems. However, the intermittent nature of these power sources necessitates using energy storage solutions that are expensive to build and maintain.  

EVs, a critical component of the clean energy transition, can serve as a decentralised energy storage system by storing excess energy in their batteries and feeding it back to the grid when demand is high.

Enabling such functionality in EVs could help the EU save hundreds of billions of euros while also helping EV owners, a study has now found. 

Benefits of bidirectional charging

With the rise in EV adoption worldwide, bidirectional charging – where the EV supplies energy either to households (Vehicle to Home, V2H) or to the grid (Vehicle to Grid, V2G) – is now reaching a critical point. 

A large fleet of EVs in a country or region like the EU can store excess energy generated in renewable facilities daily and feed it back to the grid when demand increases. The study by T&E said this approach could help the EU save €22bn a year by 2040. 

The study further estimates that this can help achieve an 8% reduction in the costs of running the energy infrastructure in the EU and help save €100bn between 2030 and 2040.  

With the V2G system, the EU could also improve its solar energy capacity by another 40%. Storing the excess generated energy in batteries, EVs could help meet 9% of the EU’s energy demand by 2040, making it the fourth largest electricity supplier without investing in storage capacity.  

Image showing multiple advantages of using the V2G approach. Image credit: T&E

How EV owners could benefit

Using bidirectional chargers could help EV owners reduce their annual electricity bills by 52%. These savings are subject to location, the vehicle’s battery size, and whether the EV owner’s house has solar panels.  

When these conditions are met, an EV owner could save up to €780 per year in charging costs while also improving the lifespan of their battery packs.

Contrary to commonly observed concerns about constant charging and discharging, this approach would help the battery pack retain an optimal state of charge and improve its lifetime by as much as 9%. 

Since bidirectional chargers only cost €100 more than regular EV chargers, the EU can reap the benefits of this approach for free. The cost of the charger will be offset within a few months. However, EV makers must ensure their chargers are interoperable and support V2G technology. 

“V2G can only take off if we ensure all EVs can work with all chargers,” said Fabian Sperka, vehicles policy manager at T&E, in a press release.

“Lawmakers can unlock the potential of this technology by deciding the EU standards for bidirectional charging. That will be a win for consumers, the environment and progress towards the EU’s climate and energy goals.”