Solar still creates waste during production and it's main obstacles to being a viable alternative are cost (which isn't so much if you're talking long-term, especially compared to nuclear) and production rates (too low to really make any sort of quick switch). That said, distributed generation is big part of the ideal long-term solution, along with conservation and effiecency. Geothermal is really the ideal energy source but it's not readily available in many areas nor is it immune to being fucked up through improper production. Most wind power is not produced in populated areas, like most power generation. You're also talking about the most extreme form of failure which is rare and shouldn't happen with proper maintenance. Nuclear powerplants take years to build so that timescale is unrealistic. You also have the larger issue of where to store the waste, I still say store it in every major city in order to ensure that people are actually invested in proper containment.