Completely free energy source? I don't think it's possible, there is cost to energy extraction and storage, but sun is a good cheap energy souce, solar panels had been getting cheaper, I had paid $40 per each 100 watt panel and I'm sure there are cheaper options. Even my portable folding panels only cost me $70 per 100 watt brand new. This is pretty cheap energy.
The problem is sun doesn't shine well everywhere. Energy being constrained and limited is what holds the natural world together, otherwise it would be runaway destructive process. In human context, it keeps societies from overextending themselves.
The problem is sun doesn't shine well everywhere. Energy being constrained and limited is what holds the natural world together, otherwise it would be runaway destructive process. In human context, it keeps societies from overextending themselves.

