The problem with those ideas is that those are chiefly experimental. The satelite idea doesn't even work, because either we will need a very loooooooooooong cable and loose most of the power on the way down, or we will have to figure out a way to "beam" it down, which there is no device capable of doing that, let alone safely. In my opinion, nuclear plants, when modern safety proticals are applied, wins hands down. Also, wind and solar are not completely safe to the environment either. Both require huge amounts of area to collect power. Not so much for wind, but if we were to attempt to build a power system on solar alone, we would have to destroy a few ecosystems to do it. As for nuclear storage, the new project is an old salt mine in Utah I believe. The old salt residues will help hold it in, but it's chief safety feature that it will simply be too deep underground to get out. How deep is too deep? Well, it is under a mountain and still below the water table at the base. Thus, since water flows downhill, even if there is a leak(it will have to leak for several miles), water will only be able to leak IN to the site, not out.