Letter to the Editor, July 5, 2013
Refusing to accept the finite
EDITOR: 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 percent per year since 1990 and is projected to increase at that rate to 2035. Subsequent calculations will use a growth rate of 1.8 percent 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 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 Energy Review, proven reserves of coal, oil, and gas equal 72 WEU, and would last for 72 years if used at the rate of 1 WEU per year. But if consumption increases at 1.8 percent per year, it will last only 47 years (to 2060) with the final year's world use at 2.3 WEU because of the 1.8 percent annual increase. A 10 fold resource increase to 720 WEU adds an additional 101 years over the previous 47 (to 2161).
Suppose we find more energy sources and increase our reserves from 72 WEU to 72000 WEU. This allows us to continue for about 400 years (to 2413) when the annual consumption will then be 1256 WEU, again because of the 1.8% per year increase. If we increase the reserves to 72,000,000 WEU, this adds a mere 389 years to the previous 400 (to 2802) when the energy consumption rate will then be 1.3 million WEU per year.
As energy is being used at a faster rate, the Earth will begin to warm, not because of carbon dioxide or global warming, but because of waste heat from the consumption of energy. Regardless of the energy source (fission, fusion, renewable, magic), after about 1200 years of 1.8 percent increases, the surface of the Earth will equal that of the surface of the Sun because if the power (rate of energy use) is used on the surface, then the surface will heat up. It's the law (of thermodynamics.) I don't know what life on Earth will be like in the future, but geometrically increasing energy consumption won't be on our list of accomplishments.
Is there a solution? Yes, but it requires the governments of the world to make coordinated logical choices to stop the geometrically increasing energy consumption. This will also affect industrial output and food production, which will then require the cessation of our geometrically increasing population. We need to realize that we inhabit a finite space with finite resources.
While working at Los Alamos National Labs in 1950, scientists were discussing the probability of intelligent life in the Universe based on the billions of stars and, as we now know, multiples of billions of planets in our galaxy alone, and came to the conclusion that space-traveling civilizations should exist and should have visited us. Enrico Fermi asked, "Where are they?" Perhaps the answer was that they too refused to accept the finite.