Renewable Energy Sources

The main sources of alternative, or renewable, energy are Solar Power, Wind Power, Hydropower, Biomass Energy, Geothermal Energy, and Hydrogen Fuel. People have really taken an interest in solar energy over the last several years. The sun is a great source of energy and many have seen the benefits of harvesting the sun's energy. Many areas of the world do not generate large amounts of solar power because they do not have enough sun year round to produce enough energy to run buildings. Kubasek (2008) only points out Texas and California as the states that have facilities that produce solar power; however, Nevada has also taken steps to open solar power plants.

Two types of solar power plants are passive and active solar systems. As far as passive solar energy goes, one builds a structure in a way that makes it a solar collector. For example, one would have energy efficient windows facing south so that sunlight can be captured. Active systems are different in that they use moving parts, such as turbines, to produce energy for heating (Kubasek, 2008).

A second type of renewable energy is wind energy. Like solar power, only areas with the right climate can use wind as a source of energy. The use of wind energy is expanding. As of 2006, 36 states had wind farms. Wind energy has sparked some controversy because it has some undesirable characteristics. Some of these are loud noise and bird injuries as a result of getting caught in windmill blades. It is interesting to note that more birds have been killed by power lines than windmill blades (Kubasek, 2008).

A third type of renewable energy source is hydropower. It is currently the most popular of renewable energy sources. Its popularity came from the fact that it produces no air pollution and is very inexpensive. There are currently around 76,000 dams in the United States. Even with its popularity, hydropower has had its share of problems. Over the last few years, around 185 dams have been closed because of their harm to wildlife and water ecosystems. Fish have been harmed by dams and the water quality below a dam is low because there is less dissolved oxygen in the water. While certain steps have been taken to make dams more environmentally friendly (such as the installation of fish ladders to help fish swim upstream), there are still problems. The future of hydropower in the U.S. remains uncertain (Kubasek, 2008).

A fourth type of renewable energy source is Biomass Energy. This is a type of energy in which organic matter is burned and energy is produced. Typical sources are agricultural waste, municipal garbage, grains, animal manure, and wood. Of course, wood is the most used source of biomass fuel. Unfortunately, wood produces a lot of pollution and there are other fuels that produce much less pollution. A type of technology that has been implemented allows us to produce electricity from methane given off by the decomposition of waste in landfills. The program that carries this out is known as the EPA LMOP (Landfill Methane Outreach Program). This program is very important because it keeps a tremendous amount of methane out of the atmosphere (Kubasek, 2008).

Yet another type of renewable energy source is Geothermal Energy. This type of energy is harvested from the heat that is trapped inside the Earth. The most common form of energy is hydrothermal energy. Homes and industry are powered by hot water reservoirs. The hottest of these reservoirs (up to 302 degrees) are located in the western United States (Kubasek, 2008).

Last but not least is the Hydrogen Fuel energy source. This type of energy source is not currently being used, but it does have promise. Currently, hydrogen is derived from methane and petroleum, but someday we may be able to derive it from water, biomass, and other sources. When we do begin using hydrogen, it will be able to be used to power cars and it will be able to replace natural gas heating and cooling systems (Kubasek, 2008).

As most people may know, solar power will continue to see the most development, although wind power will not be too far behind. While it is true that only those areas that have the most sun each year will use it the most, even some areas in the North will be able to use it from time to time. It really seems that the best area for solar energy production is the southern and western United States. These areas typically get well over 200 sunny days a year (in some cases up to 300). These areas are the real hot spots.

While Kubasek (2008) points out Texas and California as being the only states to make use of solar energy for utilities, Nevada is on its way. Just within the last year or so, Nevada Solar One was completed in the middle of the desert about thirty miles outside of Las Vegas, Nevada. It produces 64 MW of power and will be able to power thousands of homes and businesses. There are plans to expand the coverage of the solar project, which right now covers around 350 square acres. It falls into the active system category of solar energy. There are other solar power plants even larger than this (80 MW) that have been built in other areas of the world (Broehl, 2006). It is clear that solar power will continue to develop significantly over the next several years.

Broehl, J. (2006). A new chapter begins for concentrated solar power. Retrieved
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Kubasek, N. (2008). Environmental Law. Upper Saddle River: Pearson

Education, Inc.