Startup cost for solar is not all that amazingly cheap per watt, and if you include batteries it's probably more than nuclear.

UPower's design doesn't require a large body of water: http://spectrum.ieee.org/energywise/energy/nuclear/startup-d...

For setup you deliver it with a truck and bury it. Other modular nuclear designs are a bit bigger but still in the range of small natural gas plants, which are competing quite well.

If Helion works out then fission and solar will both be mostly obsolete. They'd be 50MW plants, retailing power at four cents per kWh, with no significant safety concerns.