Introduction hydroelectric Power what is it?
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Future Potential
What is the full potential of hydropower to help meet the Nation = s energy needs? The hydropower resource assessment by the Department of Energy = s Hydropower Program has identified 5,677 sites in the United States with acceptable undeveloped hydropower potential. These sites have a modeled undeveloped capacity of about 30,000 MW. This represents about 40 percent of the existing conventional hydropower capacity. A variety of restraints exist on this development, some natural and some imposed by our society. The natural restraints include such things as occasional unfavorable terrain for dams. Other restraints include disagreements about who should develop a resource or the resulting changes in environmental conditions. Often, other developments already exist where a hydroelectric power facility would require a dam and reservoir to be built. Finding solutions to the problems imposed by natural restraints demands extensive engineering efforts. Sometimes a solution is impossible, or so expensive that the entire project becomes impractical. Solution to the societal issues is frequently much more difficult and the costs are far greater than those imposed by nature. Developing the full potential of hydropower will require consideration and coordination of many varied needs. Hydropower, the Environment, and Society It is important to remember that people, and all their actions, are part of the natural world. The materials used for building, energy, clothing, food, and all the familiar parts of our day-to-day world come from natural resources. Our surroundings are composed largely of the A built environment @ -- structures and facilities built by humans for comfort, security, and well-being. As our built environment grows, we grow more reliant on its offerings. To meet our needs and support our built environment, we need electricity which can be generated by using the resources of natural fuels. Most resources are not renewable; there is a limited supply. In obtaining resources, it is often necessary to drill oil wells, tap natural gas supplies, or mine coal and uranium. To put water to work on a large scale, storage dams are needed. We know that any innovation introduced by people has an impact on the natural environment. That impact may be desirable to some, and at the same time, unacceptable to others. Using any source of energy has some environmental cost. It is the degree of impact on the environment that is crucial. Some human activities have more profound and lasting impacts than others. Techniques to mine resources from below the earth may leave long-lasting scars on the landscape. Oil wells may detract from the beauty of open, grassy fields. Reservoirs behind dams may cover picturesque valleys. Once available, use of energy sources can further impact the air, land, and water in varying degrees. People want clean air and water and a pleasing environment. We also want energy to heat and light our homes and run our machines. What is the solution? The situation seems straightforward: The demand for electrical power must be curbed or more power must be produced in environmentally acceptable ways. The solution, however, is not so simple. Conservation can save electricity, but at the same time our population is growing steadily. Growth is inevitable, and with it the increased demand for electric power. Since natural resources will continue to be used, the wisest solution is a careful, planned approach to their future use. All alternatives must be examined, and the most efficient, acceptable methods must be pursued. Hydroelectric facilities have many characteristics that favor developing new projects and upgrading existing powerplants: -- Hydroelectric powerplants do not use up limited nonrenewable resources to make electricity. -- They do not cause pollution of air, land, or water. -- They have low failure rates, low operating costs, and are reliable. --They can provide startup power in the event of a system wide power failure. As an added benefit, reservoirs have scenic and recreation value for campers, fishermen, and water sports enthusiasts. The water is a home for fish and wildlife as well. Dams add to domestic water supplies, control water quality, provide irrigation for agriculture, and avert flooding. Dams can actually improve downstream conditions by allowing mud and other debris to settle out. Existing powerplants can be uprated or new powerplants added at current dam sites without a significant effect on the environment. New facilities can be constructed with consideration of the environment. For instance, dams can be built at remote locations, powerplants can be placed underground, and selective withdrawal systems can be used to control the water temperature released from the dam. Facilities can incorporate features that aid fish and wildlife, such as salmon runs or resting places for migratory birds. In reconciling our natural and our built environments there will be tradeoffs and compromises. As we learn to live in harmony as part of the environment, we must seek the best alternatives among all ecologic, economic, technological, and social perspectives. The value of water must be considered by all energy planners. Some water is now dammed and can be put to work to make hydroelectric power. Other water is presently going to waste. The fuel burned to replace this wasted energy is gone forever and, so, is a loss to our Nation. The longer we delay the balanced development of our potential for hydropower, the more we unnecessarily use up other vital resources. |