Btw, wind turbines aren't made of concrete, the towers are metal tubes. But the blades are problematic, since they're made from fiberglass. And solar panels aren't concrete either. While - if I drive past a nuclear power plant, those are really huge concrete structures. And the problematic things about hydro plants are the reservoirs. It's flooding a vast area to build a new reservoir and changing the flow in the river that destroys ecosystems. The plant itself isn't that bad. So ideally you build it into an existing flow of water or use tidal energy instead of building a new dam. I'm not an expert on north american geography, but I bet there are some opportunities left for power plants with a lesser impact on the ecosystem.