Reservoirs may cover people's homes, important natural areas, agricultural land, and archaeological sites. So, building dams can require relocating people. Methane, a strong greenhouse gas, may also form in some reservoirs and be emitted to the atmosphere. Gosh, hydroelectric power sounds great — so why don't we use it to produce all our power?
Mainly because you need lots of water and a lot of land where you can build a dam and reservoir , which all takes a LOT of money, time, and construction. In fact, most of the good spots to locate hydro plants have already been taken. In the early part of the century hydroelectric plants supplied a bit less than one-half of the nation's power, but the number is down to about 10 percent today.
The trend for the future will probably be to build small-scale hydro plants that can generate electricity for a single community. As this chart shows, the construction of surface reservoirs has slowed considerably in recent years. In the middle of the 20th Century, when urbanization was occurring at a rapid rate, many reservoirs were constructed to serve peoples' rising demand for water and power. Since about , the rate of reservoir construction has slowed considerably.
Hydroelectric energy is produced by the force of falling water. The capacity to produce this energy is dependent on both the available flow and the height from which it falls. Building up behind a high dam, water accumulates potential energy. This is transformed into mechanical energy when the water rushes down the sluice and strikes the rotary blades of turbine.
The turbine's rotation spins electromagnets which generate current in stationary coils of wire. Finally, the current is put through a transformer where the voltage is increased for long distance transmission over power lines. Falling water produces hydroelectric power. The theory is to build a dam on a large river that has a large drop in elevation there are not many hydroelectric plants in Kansas or Florida. The dam stores lots of water behind it in the reservoir. Near the bottom of the dam wall there is the water intake.
Gravity causes it to fall through the penstock inside the dam. At the end of the penstock there is a turbine propeller , which is turned by the moving water.
The shaft from the turbine goes up into the generator, which produces the power. These are good-paying engineering, manufacturing, construction and operations jobs that can revitalize American communities. With the right federal policies , the hydropower industry has the potential to create jobs in every state, building a 21st century clean energy infrastructure. Over the past few years, the Department of Energy has been exploring the untapped hydropower generation that exists across the United States.
The report estimates that without building a single new dam, these available hydropower resources, if fully developed, could provide an electrical generating capacity of more than 12 gigawatts GW , equivalent to roughly 15 percent of current U. With an installed capacity of 2. It stands at fifth spot in the lists of biggest hydroelectric power plants in the US.
It is a concrete gravity run-of-the-river dam spanning the Columbia River in the US. Construction of the John Day Dam was completed in It features 13 turbines with each having a capacity of MW. NS Energy is using cookies We use them to give you the best experience. Continue Learn More X. Home » Power » News. Remember me. Don't have an account?
Video Url. Hydropower Vision Framework The Hydropower Vision Report includes a Roadmap that defines a range of actions needed to realize the economic and social benefits of increased hydropower in the future.
Growth: Explore the feasibility of credible long-term deployment scenarios for responsible growth of hydropower capacity and energy production.
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