Volkswagen is introducing two-way charging across a large range of its electric models. 

The firm said that all new models with its 77kWh battery pack will be able to offer bi-directional charging, and the function will be available to some existing cars via a software update. 

Vehicle-to-grid (V2G) technology allows electric cars to act as a giant mobile battery, sending power back to an energy grid or storage system on demand. Initially, VW says its system will allow vehicle-to-home transfers but it hopes it will be able to feed back into national power grids at a later date. 

Compatible models include the facelifted ID.3, ID.4/ID.5, ID Buzz and upcoming ID.7. All new 77kWh models will come with the functionality and VW says that a software update to ID. Software 3.5 will unlock it on models already delivered to customers.

The system has been trialled in a housing estate in Hudiksvall, Sweden, where it has been integrated into houses with home energy storage systems and micro energy generation. Smart algorithms help the system charge the car as cheaply as possible when there’s plenty of renewable energy around, then power the car or home as required. 

The storage system can activate the vehicle’s battery at times of high demand then recharge the battery again when demand drops. VW says it should provide enough energy to power a home for two full days and bring savings on bills thanks to the balancing of storage and demand.

There is a catch, though. Volkswagen’s V2G system uses CCS DS charging technology rather than the Type 2 AC system most home wallboxes use, and it’s currently only compatible with one model of wallbox, from HagerEnergy, although VW says it is working to enable it with other wallboxes.

The system allows smart home storage systems to use the car as an additional battery