The main substitutes for oil and gas energy include nuclear power, solar power, ethanol and wind power. Fossil fuels still dwarf these alternatives in global and domestic energy markets, but there is considerable public momentum to increase their utilization.
Fossil fuels (coal, oil, propane and natural gas) account for more than 80% of total energy consumption in the United States. Alternative forms of energy have, to this point, proven to be uneconomic substitutes; they are less efficient and more expensive (or, in the case of nuclear power, completely restricted from expanding) than fossil fuels.
The U.S. has 99 nuclear power reactors that provide an estimated 20% of all domestic electrical output. Many other countries have larger concentrations of nuclear energy; France, for example, is the world's foremost nuclear power and generates almost 80% of its electricity through it.
According to the National Aeronautics and Space Administration (NASA), nuclear power is the most effective substitute to challenge fossil fuels for future energy consumption. Compared to goal, gas, oil and ethanol, nuclear power produces negligible adverse climate effects.
More importantly, nuclear power can run much more cheaply than other clean energy forms, such as solar, wind or hydropower. Nevertheless, in the U.S. (and many other countries), governments have put a stop to nuclear expansion for decades – partly out of fears for public safety, and partly for political reasons.
Solar and Wind Power
Solar and wind power are two popular renewable energy sources. Proponents argue that these substitutes offer a clean break from the fossil fuels.
As the Institute for Energy Research points out, this isn't really true. Most contemporary solar and wind plants need constant backup power sources, usually electricity generated from a coal plant, in case it gets cloudy or the winds die down. They also have massive up-front capital costs.
The International Energy Agency (IER) has estimated that consumers currently rely on solar and wind power for between 8% and 10% of global energy use. However, the IEA acknowledges that specific policy frameworks need to be enacted, such as tax-funded government subsidies and grants, to increase the use of these alternatives.