Lithium ion batteries large enough to hold megawatts of electricity are prohibitively expensive but another potential source of battery storage is fast emerging: electric vehicles.
Vehicle-to-grid (V2G) storage allows the smart grid to use electric cars (and even hybrids) as a distributed network of lithium ion batteries that can store power at off-peak times and help power the grid when demand peaks.
Here’s how it works:
1. Power is generated from a renewable source, like wind power, and transferred to the grid.
2. Electricity flows from the grid to electric vehicles lithium ion batteries when there is excess capacity (e.g. when the wind blows in predawn hours). The power flow is reversed when demand on the grid is higher.
3. Customers can control when the smart grid can access battery power from their electric cars, which can put out enough power to run 10 houses, and even control how far the battery is discharged.