What sort of renewable energy is the best?

Most popular sources of renewable energy are wind farms, solar plants,  Bio energy and wave energy. Of course there are more. But out of these mentioned which has the best prospect of solving the world energy needs       in the long run (say 500 years).
 Wind power is used a lot these days, but I think that wind farms cannot solve the energy problem in the long run because there is just not enough wind power on the planet to capture to respond to ever growing demand of electricity.
The same goes for wave energy. Use of bio energy pushes world's food prices up, so only some forms of it can be used locally, it can't run the world.
Solar energy has the most potential, it still has to develop , to reach good cost/benefit ratio, because as of today it is very expensive and government's of the world is subsiding it, to help develop the technology. Sun has sure enough energy, we only have to find ever better ways to capture it, and transform to electricity. First more we need to find more effective solar panels, then maybe place solar panels in space, and direct laser to earth to transfer energy from these orbital solar power plants. (to cost effectively transfer materials to space I think we need to build a space elevator). Then possible we could build solar power stations on mercury, because it is close to the sun and has solid surface. How to transfer energy from mercury is not so clear, but maybe very good  batteries or the same laser, but maybe it should be directed not to earth, but to use some laser power grid in space of some sorts, where energy received by laser from one place is directed to another and so on until it reaches earth.
Tell what you think in comments!