Using the famous mass-energy relation (E = mc2) of Albert Einstein, one can arrive at the conclusion that 1 kilogram matter is equivalent to 9 × 1016 J of energy. The energy content of fuels is as follows:
1 barrel (159 litres) of crude oil º 6.1 × 109 J
1 ton of coal º 3.2 × 1010 J
1 ton of Uranium 235 º 7.4 × 1016 J
