I used the word safe deliberately as Thorium reactors are much, much safer than other forms of reactor.
Advantages:
1. They only work when you bombard them with neutrons as soon as the source is turned off the nuclear reaction stops.
2. The fact that is is stored as a liquid in proposed reactors means it disapates heat automatically through natural circulation WITHOUT any pumps.
3. Much more difficult to extract weapons grade material, so safer to build in non-nuclear countries.
4. Much less nuclear waste and waste is mainly of short duration radioactive particles.
5. Thorium is much more abundant the Uranium, so we have a much greater source of fuel.
6. All nuclear material can be consumed compared with about 2% with Uranium.
America had several Thorium reactors running in the 1960's and it was proposed the building of the worlds first Thorium reactor power station, but it was turned down as USA / UK / France / USSR had all gone the Uranium route to get plutonium as a waste product for making nuclear bombs and because Uranium was abundant and cheaper to make into a nuclear fuel.
India is currently the world's leader on Thorium reactors. Their first commercial power station should go online this year and they have currently 3 test / prototype reactors
http://en.wikipedia.org/wiki/Thoriumhttp://en.wikipedia.org/wiki/Thorium_fuel_cycleCoal contains many nuclear particles which are spewed into the atmosphere when it is burned and concentrated during the burning process to produce radioactive ash. So it is a major source of radiation pollution.
http://www.scientificamerican.com/article.cfm?id=coal-ash-is-more-radioactive-than-nuclear-waste