Experiments in a Norwegian underground plant could lead to the radioactive element thorium being developed as a safer alternative in the production of nuclear power.

Although it is lagging way behind the standard fuel uranium in its development, thorium potentially has some major advantages.

It is three times more plentiful than uranium and produces less waste. And unlike uranium, thorium's by-products cannot be made into a nuclear bomb.

The BBC's Roger Harrabin reports from a thorium test-site in southern Norway.