How do you store it for when night comes? If you live near a mountain you could pump it up during the day but not everyone is that lucky. Now what about winter

How do you store it for when night comes? If you live near a mountain you could pump it up during the day but not everyone is that lucky. Now what about winter when its overcast half the time and solar panels barely work? Just think how much additional capacity needs to be built to allow for these long periods youre not making power. Basically one has to build 3-4x the capacity to supply what one coal plant produces nonstop. The next Rockerfeller will be the one who stores gigawats on the cheap