Renewable Energy Resources in the United States.
Possible Sources of Alternative Energy?
The history of civilization is also a part of the history of the use of energy by humans. Civilization and energy use progressed from human muscle power to wood for fire in pre-historic times; to the muscle power of animals for agricultural purposes; to steam, wind, and water in the pre-industrial era; and to oil, coal, electricity, and gas in the industrial period up to present day. Non-renewable fossil fuels such as petroleum, natural gas, and coal have been the typical, and normal, source of energy all over the world. The dependency of the different nations in using these non-renewable sources of energy and its detrimental effect to the environment has been a major issue with environmental groups as well as policy makers. A solution to this is to use and develop the renewable resources that we currently have available in the United States. Renewable energy sources can be retrieved from organic matter, heat from the earth, solar, water and wind. This is why the United States should use alternative energy sources to alleviate reliance to fossil fuels and to protect the environment and start implementing changes.
The use of renewable energy is not new. More than 150 years ago, wood, which is one form of biomass, supplied up to 90% of our energy needs. With the expansion of the use of coal, gas, and petroleum, the United States became less reliant on wood as an energy source. We need to look at other sustainable sources of energy, like renewable sources, in order to use them to help us meet our demanding energy needs. In 2008, consumption of renewable sources in the United States totaled 7.3 quadrillion Btu, or about 7% of all energy used throughout the country (EIA, 2009).
Source: Energy Information Administration, 2010
About 9% of U.S. electricity was generated from renewable sources in 2008 (EIA, 2010). The production of heat and steam for industrial purposes is the largest use of renewable energy. Ethanol, a renewable resource, is used for providing heat to homes and for transportation. Renewable energy plays an extremely important role in supplying energy to the country. When renewable energy sources are used, the demand for fossil fuels is reduced. Unlike fossil fuels, renewable sources of energy (hydropower, geothermal, wind, and solar), do not directly emit greenhouse gases.
Wind is simply air in motion. Wind is caused by the uneven heating by the sun on the surface of Earth. As the Earth’s surface is made up of a variety of water and land, this causes the surface of the planet to absorb heat at different rates. One example of this uneven heating can be found in the daily wind cycle.
During the day, the air above the land heats up more quickly than the air over water. This causes the air over the land to expand and rise, and when this happens, the cooler, and heavier, air comes in to fill in the extra space. As a result, wind is created. At night, the process is reversed as air over water is warmer that that over land. In the similar process, the atmospheric winds that circle the earth are created because the land near the Earth's equator is heated more by the sun than the land near the North and South Poles (EIA, 2010).
Source: National Energy Education Development Project
With generating capacity at over 25,000 MW (megawatts), U.S. wind power already supplies enough electricity to serve the equivalent of nearly 7 million households. Although wind power provided over 1.25% of the nation’s electricity in 2008, it is projected, and capable, to provided 20% of the nation’s energy by 2030. Wind energy is a major plus to the security of our nation’s energy problem. It is an inexhaustible, domestic resource, and it helps reduce our dependence on imports of natural gas, oil, and other fuels that play a major role in global warming.
Wind requires no mining, drilling, water or transportation of fuel, and does not generate radioactive or other hazardous or polluting waste. Wind power offsets other polluting sources of energy and is proven to reduce greenhouse gas emissions. This is very important for the fact that the generation of electricity in the U.S. is the largest source of greenhouse gases (Power, 2010).
Best of all, wind power supplies affordable, inexhaustible energy to the economy. The integration of more wind power usage to the grid guarantees the creation of hundreds of thousands of new, high-quality jobs. It powers the economy without depleting natural resources. Wind has no “hidden cost” and, of course, it depends on a free fuel source – the wind.
In the 1830s, the British astronomer John Herschel famously used a solar thermal collector box (a device which uses the sun’s rays to collect heat) to cook food during an expedition to Africa (Solar, 2010). Today, people use the sun's powerful rays for many things. The sun is by far our most powerful source of energy. Sunlight, or solar energy, can be used for heating, lighting and cooling homes and buildings, generating electricity, heating water, and numerous industrial processes. Most forms of renewable energy come from either directly or indirectly from the sun. For example, heat from the sun causes the wind to blow, contributes to the growth of trees which ultimately are used for biomass energy, and plays an important role in the cycle of evaporation and precipitation that makes hydropower possible. When converted to thermal energy, solar energy can be used to heat water for use in buildings, homes, or swimming pools. It is also used to heat spaces inside homes, greenhouses, and other buildings. Solar energy can be converted to electricity in two ways: Photovoltaic (PV devices) or “solar cells” and Solar Power plants.
Photovoltaic devices change sunlight directly into electricity. Single photovoltaic cells can be grouped into panels. When these single panels are combined together, they can be used to power a number of electronics from the smallest cell like a calculator to bigger ones such powering houses. Concentrated solar power plants generate electricity by using the heat from solar thermal collectors to heat a fluid which produces steam that is used to power the generator. At the end of 2008, there were currently 11 concentrated solar power plants operating in the U.S. with 9 of these in California, 1 in Arizona, and 1 in Nevada (Solar, 2010).
Biomass power is carbon neutral electricity generated from renewable organic waste that would otherwise be thrown away, be burned, or just left on the ground. Examples of this organic waste include, but not excluded to, agricultural waste, debris in forests, and scrap lumber. Using biomass power will allow us to take the natural resources we have already that are not needed anymore and turn them into clean, renewable energy. This type of energy even reduces greenhouse gas emissions. Biomass offers significant consumer benefits, environmental benefits, protects the quality air we have, improves forest health, and offers the most dependable renewable energy source as of yet.
As organic waste decomposes it slowly emits methane gas and carbon dioxide. Biomass power plants use this to turn waste into fuel which then generates electricity. During this process of generating electricity, the carbon dioxide emissions are reduced and the methane gas is totally eliminated. This shows that using biomass power reduces the amount of greenhouse gases released into the ozone. In fact, the use of biomass power removes over 30 million tons of carbon dioxide annually (Biomass, 2008). This is possible by preventing the release of greenhouse gases from organic waste and replacing fossil fuels.
The biomass power industry removes over 68.8 million tons of forest debris annually, improving forest health and dramatically reducing the risk of forest fires (Biomass, 2008).Plus, biomass power takes away millions of tons of garbage from landfills. It also totally eliminates the need to burn waste and debris, and at the same time reducing the need to use fossil fuels. The fossil fuels that cause acid rain and smog. Through this, biomass power helps to ensure that we have quality air to breath.
Biomass power is an extremely reliable source of energy since unlike hydro, solar, and wind power, it is not affected by the weather or changes in the environment. It can provide a dependable and steady flow of energy all the time. The reliability of biomass power allows local utility companies to easily and efficiently add biomass to their base load supply to meet growing energy demands. Currently, the biomass industry generates 15 million mega-watt hours of electricity annually.
With over 80 facilities in 20 states right now, biomass power is providing a little over half of the United States’ renewable electricity. Across the country, biomass can account for over 18,000 jobs (Biomass, 2008). In the southeastern states that can’t provide energy through wind or the sun, biomass power can play a major role. Biomass power holds the greatest opportunity for achieving a strong national standard for renewable electricity.
Hydropower (from hydro, meaning water) is energy that comes from the force of moving water. The water cycle is the continuous fall and movement of water. The sun evaporates the water on Earth and draws it upward. When that water vapor hits the colder air in the atmosphere, it condenses which then forms clouds. The moisture in the clouds will sooner or later fall as either snow or rain, refilling the same oceans, lakes, streams, etc. that water was evaporated from. Gravity moves the water from high ground to low ground. The force of this moving water can be very powerful. Harnessing the power of water is called hydropower. As long as the water cycle continues, we won’t run out of this energy source.
It’s easier to build a hydro plant where there is a natural waterfall. The perfect place for a hydro plant is Niagra Falls, which was the place where the first hydro plant was built. Dams, which are controlled waterfalls, are the next best way to use water to generate energy. There are about 80,000 dams in the United States today, but only about 3% of those have hydro plants. This is because most dams are built for agricultural purposes and flood control rather than energy production. Hydro plants use dams for two reasons. First, a dam increases the height of the water flow. Secondly, it controls the power of the flow of the water. This is important because this allows the hydro plant to dictate how much power and when the power is generated.
Generating energy using hydropower is by far the cheapest of all the renewable energy available since once a dam is built the main source of power, in this case water, is free. Hydro plants are sturdy and do not require expensive equipment. They are dependable and have a low maintenance cost. All of these factors contribute even more to hydropower being a cheaper way to produce energy than coal or nuclear power plants. The question is, how much electricity do we get from hydropower today? It all depends on the amount of rainfall. Hydro plants bring in 5-10% of the electricity produced here in the U.S. 73% of that percentage of electricity produced come from Oregon, Idaho, and Washington State each year. Currently, hydro plants generate about 78 million Kilowatts of electricity in the United States. That’s the same amount of energy produced by 80 large nuclear plants (Need, 2008).
Geothermal power uses the natural sources of heat inside the Earth to produce heat or electricity. Most geothermal power is generated using steam or hot water from underground. This type of power produces few emissions and is always available. Direct-use systems, geothermal heat pumps, and the use of deep reservoirs are current techniques used to efficiently use geothermal power.
In direct-use geothermal systems, a well is drilled into a geothermal reservoir to provide a steady stream of hot water. In this process, water is brought up through the well, and then a mechanized system delivers the heat for whatever use it is intended for. When the water cools down, a disposal system will either send it back underground to repeat the cycle or send it to a pool above ground for storage. This geothermal hot water is used for numerous things including to raise plants, heat buildings, or used in industrial processes. Geothermal reservoirs appropriate for direct-use systems are widespread throughout the western United States.
Geothermal power plants convert hydrothermal fluids (hot water or steam) to electricity. The oldest type of geothermal power plant uses steam, accessed through deep wells, to directly drive a turbine to produce electricity. These plants are the most common type of geothermal power plants in operation today. They use extremely hot water (above 300 degrees F), which is pumped under high pressure to the generation equipment at the surface. The hot water is vaporized and the vapor in turn drives turbines to generate electricity. California, Hawaii, Nevada, and Utah currently have operating geothermal power plants.
Estimated subterranean temperatures at a depth of 6 KM.
Geothermal heat pumps are used for heating and cooling areas, and for heating water. This type of energy producing power is based on the fact that below the Earth’s surface the temperature remains at a constant. It stays warmer in the winter and cooler in the summer. A geothermal pump in the winter transfer the Earth’s heat and stores it in a building. In the summer, it reverses this process. A heat pump is made up of a series of pipes buried in the ground around the area that is to be cooled or where water is to be heated. Throughout the pipes there is fluid, and the main objective of this fluid is to either distribute heat to the ground or absorb heat from the ground. These pumps can virtually be used all over the United States.
It is imperative that these types of energy resources be used. These renewable resources have a lesser chance of causing a global catastrophe, like the Exxon-Valdez and BP incidents.
On March 24th, 1989, Exxon Valdez, an oil tanker on its way from Valdez, Alaska to Los Angeles, California hit the Bligh Reef in Prince William Sound in order to avoid hitting ice. Six hours of running aground, the tanker had spilled 10.9 million gallons of crude oil out of its 53 million gallon tanks. Out of the eleven tanks on board, 8 were destroyed. Over 1,100 miles of Alaskan coastline was affected by the spill. Up to that date, this was the largest oil spill in United States history (Cleveland, 2010).
The response to the Exxon Valdez involved more personnel and equipment over a longer period of time than did any other spill in U.S. history. Providing food, equipment, fuel, lodging, and other resource problems made this the largest challenge in response to the oil spill. At the height of the response, more than 11,000 personnel, 1,400 vessels and 85 aircraft were involved in the cleanup. However, the scale of this spill will likely be, if by now it hasn’t already, eclipsed by the Deepwater Horizon oil spill originating in the Gulf of Mexico.
BP and Deepwater Horizon
The Deepwater Horizon oil spill, also known as the Gulf of Mexico Oil Spill or the BP Oil Spill, is a large ongoing oil spill caused by an explosion on the Deepwater Horizon offshore oil platform fifty miles southeast of the Mississippi River delta on April 20, 2010. 126 of the workers onboard the oil rig were safely evacuated but 11 were missing. The Deepwater Horizon sank in about 5,000 feet of water on April 22, 2010. On April 23 the U.S. Coast Guard suspended the search for missing workers who are all presumed dead.
The sinking of the platform caused crude oil to gush out of a 5,000 foot pipe that connects the drilling platform to the bottom of the ocean floor. When the blowout preventer could not be activated, government officials estimated that over 1,000 barrels of oil per day would be spilled out in to the Gulf of Mexico. Eight days later after the initial explosion of the oil rig, that estimation rose to over 5,000 barrels as three leaks were found on the pipes a mile below sea level. That equals about 200,000 gallons of oil a day.
The oil slick produced by the Deepwater Horizon oil spill has covered as much 28,958 square miles, which is about the size of the state of South Carolina, in the Gulf. These changes day by day depending on what the weather conditions and currents are like. Oil had reached Mississippi, Alabama, Florida, and Louisiana by the first week of June. By this time, there were a large number of wildlife deaths. In May and June, scientists discovered oil plumes far into the Gulf of Mexico. Oil plumes are heavily concentrated clumps of oil that are heavier than water and deplete the oxygen in the water. These oil plumes raised concerns about ecological harm far below the surface that would be a little difficult to assess (Encyclopedia, 2010). These plumes are dangerous to the wildlife in the water of the Gulf of Mexico and have a very large chance to affect ecosystem and the economy of the cities on the cost of the Gulf. The U.S. Fish and Wildlife Service reported that up to 32 National Wildlife Refuges could potentially be affected by the spill (U.S., 2010). By June 2, 2010, the National Oceanic and Atmospheric Administration (NOAA) had banned fishing in about 36% of federal waters, or 86,895 sq mi (229,270 sq km) of the Gulf (NOAA, 2010). These incidents caused by human incompetency combined with fossil fuels not only show that it can cause serious harm to wildlife and people directly but also puts stress on thousands of jobs. Without any major consequences like with Deepwater or Exxon, the five major renewable resources that we have currently available in the United States can be used, if properly, to produce the same amount of energy that fossil fuels currently produce.
Issues with Renewable Resources
As good as they sound, and are, these sources do run into obstacles. Take wind power for example. As the country slowly but gradually starts using wind power, an issue with this is the large amount of land, or coastline, needed to build wind plants on. This interferes with other priorities such as farming and the building of homes. Dams being used for hydropower runs into problems too even though they burn absolutely no fuel. Using dammed rivers can ultimately alter wildlife habitats or change river systems. Salmon, for example, may not be able to swim upstream if river systems are altered. The operation of hydro plants may bring up dissolved metals into the water, affecting the quality. Hydropower operations may increase silting, change water temperatures, and lower the levels of dissolved oxygen.
Two problems with solar energy are the amount of sunlight that arrives at the Earth's surface is not constant. It depends on location, time of day, time of year, and weather conditions. Since the sun doesn't deliver that much energy to any one place at any one time, a large surface area is required to collect the energy at a useful rate.
As the need for clean, renewable energy increases, and the world more urgently seeks alternatives to finite supplies of oil, coal and natural gas, priorities will change. And as the cost of these readily available renewable resources continues to decline, due to technology improvements and better generation techniques, geothermal, solar, wind, biomass, and hydro power will become increasingly feasible as a major source of electricity and mechanical power.
EIA. (2009). Renewable Energy Explained. Retrieved July 19, 2010 from http://tonto.eia.
Cleveland, Cutler J. (2010). Exxon Valdez Oil Spill. Retrieved July 19, 2010 from http://www.eo
Encyclopedia of Earth, The. (2010). Deepwater Horizon Oil Spill. Retrieved July 19, 2010 from
U.S. Fish and Wildlife Service. (2010). FWS Deepwater Horizon Oil Spill Response. Retrieved
July 19, 2010 from http://www.fws.gov/home/dhoilspill/index.html.
NOAA. (2010). Office of Response and Restoration. Retrieved July 19, 2010 from http://respons
EIA. (2010). Wind. Retrieved July 19, 2010 from http://tonto.eia.doe.gov/energyexplained/index
Power of Wind. (2010). Wind Energy 101. Retrieved July 19, 2010 from http://www.powerofwin
Solar. (2010). Energy Explanied. Retrieved July 19, 2010 from http://tonto.eia.doe.gov/energy
Biomass Power Association. (2008). About Biomass. Retrieved July 19, 2010 from http://www.u
Need.org. (2008). Hydropower. Retrieved July 19, 2010 from http://www.need.org/needpdf/ info