Thorium
Thorium would make a good source of nuclear fuel because it makes much less waste and is four times as common as uranium. It does not need the wasteful process of enrichment. It makes 3,200,000 times as much energy as coal and 200 times as much energy as uranium. Scientists believe that there is enough of it to power the world for thousands of years. Thorium has been used for various purposes since the 19th century. It is an alloying agent in magnesium and is also used as an industrial catalyst.