Last I heard thorium reactors are around 50 years off. Considering if we started building a traditional PWR right now, it would be be 2-4 years before even that would be online (in the U.S.). So 50 years is probably the minimum.
Wind and Solar don't have the output to replace nuclear or coal, and probably never will, they will most likely only be supplemental.
We are closely approaching an energy crisis in this country, where supply won't match demand. While alternative energy source R&D needs to continue, we also need to act now, not later.
A 10 megawatt hydrogen plan just isn't going to cut it. My single reactor plant puts out over 1600, that's for 2 years straight 24\7 before needing a refuel. Coal can match nuclear output, but it is literally continually refueled. Once a nuclear plant starts burning it's fuel, it practically runs itself. They are incredibly reliable and safe, barring a natural disaster of epic proportions. If countries prefer polluting themselves with the byproducts of coal, then I guess we can live in a nuclear free world, that's an awfully big step backwards in my opinion. You're talking at the very least 50 years before a power source comes along able to replace coal.
I just don't understand the outrage and fear when it comes to the Japan nuclear situation. Where is the international outrage when a coal mine explodes, when a fly ash pond decimates miles and miles of land, when mountain tops are literally torn apart to get at coal, when mercury from coal plants is linked to human disease, etc. Yet even after Three Mile Island and Japan, when nuclear power shows how safe it can be even when the worst possible scenario happens, it's still treated as a nuclear bomb about to go off at anytime.