The World's Finite Resources
How long do the people of Earth have before we run out of energy? According to the DOE/EIA 2011 report, world energy consumption has increased by 1.8% per year since 1990 and is projected to increase at that rate to 2035. Subsequent calculations will use a growth rate of 1.8% per year. Funds in an account that offers 1.8% annual earnings would double every 39 years. Annual world energy consumption varies depending on the source, but an average seems to be about 500 billion billion joules. A joule in a unit of energy similar to the familiar kilowatt-hour; one kilowatt-hour equals 3.6 million joules. The population of Earth is currently using energy of all forms (coal, oil, gas, nuclear, and renewable) equal to the annual electrical energy usage of 12 billion average U.S. homes. To simplify the calculations, I'll use 1 WEU (World Energy Unit) as the current world annual energy consumption. What energy resources are available for the world to use? According to the BP 2010 World En