>> solar needs the grid to be even close to viable >This was true 20 years ago and will be laughable 20 years from now. So in 20 years the batteries are able t

>> solar needs the grid to be even close to viable >This was true 20 years ago and will be laughable 20 years from now. So in 20 years the batteries are able to store half a year worth of electricity? That's quite a lot of MWh in your house. The whole world doesn't live at the equator.