> The people buying the batteries and the government's capital.
The former should be allowed to make their own decisions. I agree that the latter should probably be kept out of this: government is usually not very good at making these decisions. But alas, in many places they play a huge role in the electricity supply and distribution.
> The former should be allowed to make their own decisions.
Yes, but that's how we arrive to local economical maxima that are much, much closer to the global minimum that to the global maximum. The personal decisions aggregate, after all.