“GREEN MACHINES”
ALTERNATIVE ENERGY
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| The largest photovoltaic solar power plant in the United States was completed in December 2007 at Nellis Air Force Base. The solar arrays produce approximately 15 megawatts of power. Credit: Image from U.S. Air Force, courtesy of Wikipedia. |
The world’s present energy needs are primarily met by the burning of carbon-based fossil fuels. Gas, oil, and coal are burned to power engines, heat your house, and produce electricity. Not only does this increase the carbon dioxide levels in the atmosphere, a cause of global warming, but these are non-renewable resources. It is estimated that the vast stores of these resources will be all but depleted in the next century or two. Nuclear energy is another source currently used, based on the fission of uranium isotopes. The future of nuclear energy may hold great potential, but it has already been shown to be dangerous in the case of a malfunction or if not properly monitored (as in the case of Three Mile Island in the United States and Chernobol in the Ukraine). Nuclear reactors produce radioactive waste that must be disposed of and can be deadly for hundreds of years, and nuclear reactors can also be used by countries to develop weapons-grade uranium, or become potential sites of terrorism.
Science and industry are developing alternative energy sources, including:
• Hydrogen fuel cells: presently a very clean but as yet a relatively inefficient way of producing energy by chemical reaction of hydrogen and oxygen
• Windmills: Wind energy is beginning to be employed in many parts of the world. Windmills presently produce a fraction of the total electricity in the world (about one percent), but produces about 20 percent of electrical energy in Denmark. It is expected that wind-produced energy will become be more important as time goes on
• Wave energy: capturing the energy of ocean waves to produce electricity
• Solar energy: Light from the sun strikes photoelectric cells to produce electricity
• Algae: algae are fed carbon dioxide to produce large quantities of biofuel, a much more efficient way than fuel from corn or other plant crops
The dream of inexpensive, unlimited energy from nuclear fusion (which produces no radioactive waste) still appears elusive (although it occurs in all stars), but it is not impossible that new innovations in the next century will make a fusion reactor a reality.
WHY SHOULD I CARE?
Your very existence (heating, cooling, cooking, illumination, transportation) and quality of life will be a function of how well we manage our energy resources in the future, which includes a drastic reduction of the burning of fossil carbon-based fuels such as gas, oil, and coal. We all have a vested interest in the development of efficient, renewable, affordable, and clean energy sources in years to come.
WEB RESOURCES
This website lists the Top 5 Wacky Forms of Alternative Energy.
https://science.howstuffworks.com/five-forms-alternative-energy.htm
This website provides a general overview of alternative forms of energy.
https://www.benefits-of-recycling.com/alternativeformsofenergy.html
This is a kids site provided by the US Energy Information Agency.
https://tonto.eia.doe.gov/kids/
