Originally Posted by
Wikiy
Sorry, 6,5x10^19 J. Which is 65 quintillion on the short scale (million-10^6, billion-10^9, trillion-10^12, quadrilion-10^15, quintillion-10^18) and 65 trillion on the long scale, used by most European countries (million-10^6, milliard-10^9, billion-10^12, billiard-10^15, trillion-10^18). Which is, as Fuzzzie also said, 16 megatons of TNT.
Oh, and about fusion power, it would technically work for half of the elements, but under the right conditions. The "fuel" used most is a mixture of dilithium and tritium (2 types of hydrogen besides the main one, but they're extremely abundant on Earth, so you don't need to worry about fuel shortages in future.