Thorium

 Here's an interesting video about using thorium instead of uranium to provide nuclear power.  Thorium is much, much cheaper than uranium, because there is more of it in the earth's crust and because it is 200 times more productive than uranium.  It is safer, and its waste is radioactive for only a few decades compared to 10,000 years or more for the waste from conventional reactors.  

The video gives no estimates of cost per MWh of output, so it's not clear whether it would be cheaper than conventional uranium-fired nuclear.  Demonstration power stations are due to start running next year (2025) and in 2026, so we shall see.  But don't expect it to make a difference over the next ten years, which is when we need to slash emissions as much as we can to prevent a 2.5 to 3 degrees rise in global temperatures by 2100.