In 2008, according to the Energy Information Administration (EIA), the most used source of RE in 2008 was biomass. In the following graph from the EIA it can be seen where biomass and other RE sources fall in total US energy usage.

The availability of biomass is copious because it is derived from the energy stored in organic material of  plants and animals. This is the most vastly available resource because humans and animals will continually create waste regardless. Examples of biomass sources are wood, crops, manure, certain types of garbage, and alcohol fuels. There are many ways which this stored energy can be released. There are several ways which biomass can be harvested for energy such as burning for electricity, bio-diesel, ethanol fuels, and bio-gas from methane gas.

Although biomass was the most used source of RE in the world, it does not produce the highest amount of energy. Hydroelectric power is the main provider of RE in the US for 2008. Out of all the electricity in the US used in 2008 hydroelectric power accounted for 6%. This technology is the oldest RE source and is relatively simple. Water can either descend from a high point or just be swiftly moving, as long as it has high force behind it as it flows through pipes and pen-stocks. As it does this the water pressure pushes against blades which turn the generators. Once the generator is spinning electricity is produced and is harnessed. A main concern with the use of hydroelectric power is the ability for fish have access to rights of way and be able to safely pass by these systems (Energy Information Administration).

Geothermal power is one of the least commonly talked about of all the available renewable resources, but it has already made an name for itself by making up 5% of RE use in 2008. Heat  is continually produced deep inside the Earth and technologies have been developed which allow recovery of this heat and steam or boiling water and then use it to heat buildings or for conversion into electricity. The pumping of heated underground water or steam to the surface releases enough energy for people around the world to use this technology to heat and run the electrical needs of homes. A downfall of this technology is the difficulty locating these  geothermal hotspots. The only method to do so is drilling wells and testing the temperature of the water found on the site. Most geothermal heat that is within the US is along the Western United States. One particular area of high activity is called the ring-of-fire (shown below), which encircles the entire Pacific ocean (Energy Information Administration).

The media frequently talks about wind and solar power, shedding little light on the other forms of RE which contribute greatly to the 7% of energy derived from RE in the U.S. The top ranking contributors to total U.S. RE use in 2008 were biomass (53%), hydro power (34%), wind power (7%), geothermal (5%), and solar (1%) (Energy Information Administration). There is an obvious desperate need for more usage of RE sources. This is not only for environmental concerns of pollution, but also because of renew ability and the amount of accessibility to needed resources. There are many efficient alternatives that in the future we can hopefully increase use of tri-fold, especially in the fields of biomass, hydro power, and geothermal energy. Overall RE has many various technology options that can be collectively implemented to help preserve the planet's future and our own security in the energy and fuel battle. If the US incorporated more energy efficient technology then 3.1 gigatons of carbon dioxide emissions could be prevented from being released. In an article called "The Invisible Green Hand" in California Management Review, the authors can be quoted saying, "Technologies are so cheap they actually can make us money, so why aren't they more widely adopted?" (Maram and Kulatilaka, p196). This is a great questions and the main issues preventing this are with funding and ecosystem/wildlife well being. Over the past 10 years statistics have shown that coal costs .07-.09¢/kWh. In contrast investments in energy efficiency cost approximately .03¢/kWh (Maram and Kulatilaka). The US has more than the necessary potential to be completely independent of energy failures due to conflicts among those in control of fossil fuels, as well as greatly reducing the impact that human actions have on the environment through clean, RE alternatives. 

Tabitha Kelly

Works Cited

Garcia, John P. "Green Corporate Tax Incentives - Wind Technologies." Corporate Taxation 36.6 (2009): 16-19. Print.

Maram, Martha, and Nalin Kulatilaka. "The Invisible Green Hand." California Management Review 51.2 (2009): 190-98. Print.

Renewable and Alternative Fuels. Energy Information Administration, Maram, Martha, and Nalin Kulatilaka. "The Invisible Green Hand." California Management Review  51.2 (2009): 190-98. Print.16 July 2009. Web. 20 Nov. 2009.