Total World Energy Use (2003)
See the section on units for explanations of quads, TW, etc.Estimating total world energy use is slightly tricky, and different means of doing it may disagree by a few percent. Nevertheless, total world primary energy consumption in 2003 was roughly 400 quadrillion Btu's, and other numbers as in the following table (see references below for more details).
| in Btu's | metric power | oil equivalent | |
|---|---|---|---|
| Total: | 400 quads/year | 13 TW | 188 million bboe/day |
| per person: | 70 million Btu/yr | 2.2 kW | 1 bboe/month |
| US: | 90 quads/year | 3 TW | 42 million bboe/day |
| US per person: | 340 million Btu/yr | 10 kW | 5 bboe/month |
| World Electric: | 170 quads/yr | 5.7 TW (1.9 TWe) | 80 million bboe/day |
| US Electric: | 38 quads/yr | 1.3 TW (0.46 TWe) | 18 million bboe/day |
| World: oil | 144 quads/yr | 4 TW | 70 million bboe/day |
| World: natural gas | 93 quads/yr | 3 TW | 44 million bboe/day |
| World: coal | 102 quads/yr | 3.4 TW | 48 million bboe/day |
| World: nuclear | 24 quads/yr | 0.8 TW | 11 million bboe/day |
| World: hydro | 24 quads/yr | 0.8 TW | 11 million bboe/day |
| US Residential: | 21 quads/yr | 0.7 TW | 10 million bboe/day |
| US Commercial and Industrial: | 50 quads/yr | 1.6 TW | 23 million bboe/day |
| US Transportation: | 27 quads/yr | 0.9 TW | 13 million bboe/day |
Note that electric power consumption, averaged through a year, is quite a bit less than installed capacity; some electric generators are used almost full time (nuclear reactors in particular), some only when demand is high, and some generators have variable supply (wind turbines and hydroelectric dams in particular).
History of energy use
Prior to the 20th century, human energy use was dominated by fuels recently derived from the natural world: burning wood, or agricultural wastes, for example. Total primary production of the biosphere amounts to over 200 billion metric tons per year. In energy terms that is about 100 billion tons of oil equivalent or about 4000 quads - i.e. about ten times current human energy needs. Almost all of that production is consumed in the continued operation of Earth's many ecosystems (humans divert about 1%). For reference, total incoming solar energy to the Earth is close to 4 million quads/year, or 10,000 times current world energy needs.The rise in use of fossil fuels through the 19th century replaced current bio-mass with the ancient variety preserved in oil, coal, and natural gas deposits. Thanks largely to benefits from fossil fuels, world population nearly quadrupled from 1.6 billion in 1900 to 6.1 billion in 2000. Human energy use grew even faster, from about 21 quads in 1900 to over 350 quads by 2000. That factor of roughly 16 growth in energy use was matched by a factor of 16 growth in constant-dollar world GDP; more on that when we discuss economic issues.
The following chart shows growth in primary energy consumption since 1965 using data from British Petroleum's "Statistical Review of World Energy 2004" and the US Department of Energy's International Energy Review 2002 (released 2004). The EIA report includes more renewable sources than the BP one, though that doesn't entirely explain the differences in their estimates. At least they're close and the trends are the same.
References:
Vaclav Smil,
BP Statistical Review of World Energy 2004:
http://www.bp.com/subsection.do?categoryId=95&contentId=2006480
The entire data set from the review is available for download as
a spreadsheet.
US DOE Energy Information Administration, Annual Energy Review 2003:
http://www.eia.doe.gov/emeu/aer/consump.html, see table 2.1a for
consumption by sector.
US DOE Energy Information Administration, International Energy Review 2002:
http://www.eia.doe.gov/iea/contents.html, see table 2.9 for
primary energy production and B.1 for world population.