Add 5 tiers of transformators for better control over the electric supply network. The transfer power for each tier is 1MW, 10MW, 100MW, 1GW, 10GW with efficiency of ~98%
If you put one power grid with one battery (charged), connect a second power grid (without everything, just a couple of power poles) via a transformator, so that the first one is fed into it. If the battery is installed in the second grid, more energy will be transferred to the battery than it was
