The uptake of EVs in the years ahead will add up to staggering battery capacity, mostly sitting idle on driveways. The two-way flow of electricity from EV batteries, known as vehicle to grid, could not only enable power systems to rely on intermittent renewables, but could also be the trump card for network operators to respond to grid disturbances. However, there are still a few catches to be worked out, as Marija Maisch explains.
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