Other Alternative Energy Sources

There are many alternatives to fossil fuels besides photovoltaics. Of course, like all forms of energy, each of these types also has its pros and cons associated with it. Here are some alternative forms of energy – biofuels, hydroelectric, wind, and geothermal – and some of the advantages and disadvantages of each.

Hydroelectric

Most hydroelectric power requires the building of a dam. It is best to build the dam where there is already an existing lake. Once built, water flows through tunnels to turbines that drive generators. It is also possible, though much less common, to build a station right next to a river. This creates less environmental impact, but it is also more difficult to control the power produced (water cannot be stored for later use, nor can the flow of water be controlled).

Benefits
• Water is a renewable, inexhaustible fuel source.
• Hydroelectric power can be used throughout the world
• Little to no waste or pollution produced.
• Extra water can easily be released to coincide with high demand.
• Once built, there is little additional cost.
• No harmful air emissions are produced.
• It is more reliable, efficient, and inexpensive than other forms of alternative energy.

Disadvantages
• Dams can have many negative effects on the surrounding environment. Fish can become extinct, beautiful lands can be swallowed up by the resulting reservoir and lost forever, and the natural, delicate habitat of many species of plants, fish, and animals can be destroyed.
• Water quality is affected.
• Humans may have to relocate their homes.
• Floods can occur.
• They often require large transmission lines.

To see how hydroelectric power works, check out:

http://ga.water.usgs.gov/edu/hyhowworks.html

Wind

Wind power, along with solar power, is becoming one of the most popular current alternative energy sources of power. Wind propels the blades of wind turbines which, in turn, cause magnets to rotate, and electricity is created.

Benefits
• No emissions are released into the air.
• Once built, windmills are free to run, requiring only general, regular maintenance.
• Renewable resource.
• Good for remote areas.
• It’s a domestic source of energy.
• Benefits rural economies (wind farms can be built on farms or ranches, and wind turbines do not require much land).
• Low price to consumers.

Disadvantages
• Wind is not constant – when the wind isn’t blowing, electricity isn’t being created.
• Many consider wind farms to be eyesores.
• Wind turbines can affect bird migration patterns and can be dangerous to birds (the blades move so quickly that birds do not always see them).
• Sometimes the best wind sites are far away from where electricity is needed.
• Some noise is produced by the blades.

For more information on wind energy, check out:

http://www.awea.org/

Biomass

Biomass is organic matter that is processed into energy. It is burned or converted into gas or biofuel. For instance, Ethanol is a type of transportation fuel made from biomass.

Think of garbage as a renewable resource. We certainly produce enough of it. And when garbage decomposes, methane is produced. This methane can be piped and used to produce electricity. Wood and other vegetation can be burned to create energy. Vegetable oil can be used in a similar fashion to gasoline, but it is safer – it has a higher flash point.

Benefits
• Garbage and agricultural organic waste can be used to create energy – nothing is wasted or simply sent to a landfill.
• There is worldwide appeal – all countries could produce some sort of biofuels. We already know how to grow these products.
• Fuels produced by fementation or pyrolysis are clean burning.
• Safer than most fuels.
• Produces fewer emissions that fossil fuels – less SO2 and less NOx. Also produces less CO2, but still creates a significant amount.
• Jobs in rural climates are created and retained.

Disadvantages
• Burning these fuels still creates air pollution, similar to that created by the burning of fossil fuels. The CO2 produced his still significant, but less than that created by fossil fuels.
• Deforestation is already a problem, and the problem could be increased by a growing popularity of biofuels.
• Farmers growing plants for biofuels would compete for land with those growing plants
for food.
• It is still pretty expensive.
• Many say that about as much (or more) energy is used to grow and harvest biomass as is actually produced.

For more information on biomass energy, check out:

http://www.appanet.org/utility/index.cfm?itemnumber=13706

Geothermal

Whereas photovoltaics focuses on energy beyond the earth, geothermal energy focuses on energy stored within the earth. There is much heat energy present beneath the earth’s surface. This heat can be used to directly heat homes, or it can be used to create electricity.

Benefits
• Geothermal systems are the most environmentally friendly type of heating and cooling technology available.
• Does not require much land.
• Renewable and sustainable.
• Continuous generation of power.
• Pretty much free to run once a geothermal power station is set up.

Disadvantages
• The heated rock must be close enough to the surface for our current drilling technology – it is not a source of energy that all areas could use. It is also important that the type of rock above can easily be drilled through.
• Not only is energy “released” when drilling, but hazardous gases and minerals may also be released.
• While it is a fairly constant source of energy, there is a chance that a site could stop producing energy for decades at a time!

For more information on geothermal energy, check out:

http://geothermal.marin.org/

For more information on alternative sources of energy, including photovoltaic power, check out:

http://en.wikipedia.org/wiki/Energy_development