������

According to the United States Energy Information Administration, the amount of energy supplied by all fuel sources across the world is tremendous: 155,481 teraWatt-hours as of 2014, the latest year on record.

In order to meet this enormous energy demand in a given year, we need to burn 24 billions tonnes of coal, or 12 billion tonnes of oil, or a bit less of natural gas (10.4 billion tonnes).That's for fossil fuels.

If we were to use only conventional nuclear energy to power the world, we would need to consume approximately 7,000 tonnes of nuclear fuel (enriched uranium or mixed oxyde).

However with nuclear fusion, only 867 tonnes of hydrogen would suffice...

Forbes magazine has a detailed article on this topic .