Well, for that matter, we don't have enough nuclear power production capacity to meet our needs either, so I don't entirely see your point. Reducing the amount of power we're producing with fossil fuels will mean needing to increase our production from other sources, but it doesn't mandate that we have to increase it from a particular source.
My point is that fossil fuels and nuclear power are the only two types that scale efficiently with current technology. Everything else doesn't scale as well. Not sure how else to word that, and that's exactly what I meant up there.
It has nothing to do with current capacity. Nuclear has lost a lot to debates much like this one; however, if we wanted the capacity, nuclear would step up and fill it in at a reasonable price. The same amount of power generated by the alternatives would be astronomically expensive. That's one of the problems that plague the alternatives you've named: either they are far too expensive to use at any kind of large scale, or suitable locations are in thin supply, or power output fluctuates unsuitably with a change in weather, and so on. They just can't compete.
The current research into nuclear is making it even cheaper and safer (thorium, etc); the current research into the alternatives is making them cheap enough to be possible with significant demand.
The reasonable price you talk about doesn't include the cost of disposal. Whatever about providing electricity to be consumed at scale, dealing with radioactive waste has not been successful at small scale, why would it work at large scale? A lot of people display hubris about the merits of the on paper research reactors, what about their unknown unknowns?
* We currently have massive political pressures blocking the production of nuclear reactors. There is no problem in building it, the problem is in the politics.
