Energy Consumption

The remaining world energy resources are large, compared to world energy consumption. To make it easier to compare the numbers, this article uses SI units and prefixes and measures energy rate (or power) in watts (W) and amounts of energy in joules (J). In 2004, the worldwide energy consumption of the human race was 15 TW (= 1.5 x 1013 W) with 86.5 rom burning fossil fuels. This is equivalent to 0.5 ZJ (= 5 x 1020 J) per year, although there is at least 10% uncertainty in the world's energy consumption. Not all of the world's economies track their energy consumption with the same rigor, and the exact energy content of a barrel of oil or a ton of coal will vary with quality.
See more at Wikipedia.org...

The use of energy as a source of heat or power or as an input in the manufacturing process. (DOE3)