You also need to consider how this changes in scale. For example in the US many of the best wind locations are taken. Additionally, long haul of power (eg 500+ miles) is best done with DC transmission lines and all of ours are AC (check out what Canada and China are doing with their transmission lines) Similarly with solar as the best locations are in the South.

I was an energy lobbyist and was appalled at how ignorant the government was on how to plan for this. The hearings were crawling with fossil fuel friendly lobbyist who kept throwing money wrenches into the discussions. And this easy to do, just throw money at a bunch of average ignorant people and it will get screwed up every time.