Just for interest, the power storage systems they are planning to use are described here. The copyright on the datasheet is 2023, so I gather this is pretty new.

Each system comes in a semi-truck trailer-- pretty big. The rated capacity is 400 kWh. To put that in perspective, the capacity of a Tesla Model Y is 75 kWh. So a semi-trailer sized battery can charge only 5-6 electric cars from 0 to full.

This makes sense, I suppose. The battery must make up a large part of an electric car, and such batteries probably have higher energy density than these storage systems. Still, I guess it is good to know that a semi-sized battery is not going to power a small city or something, but rather maybe charge all the electric cars on one block.