The Hydroelectric Energy is Ideal For Our Future

Great dams hold back huge bodies of water to build pressure and then release them and capture the energy of rush water. Water behind the dam is constantly flowing from creeks, streams and rivers fed by rain falling hundreds of miles upstream and snowmelt flowing down from the mountain ranges.

Entire cities are powered by electricity created with renewable energy generated from hydroelectric power. This is not new technology as water wheels were used thousands of years ago to grind corn and pump water in Greece.

Anyone who has experienced a flood knows the amazing force created by rapidly flowing water. With water flowing from a height creates that same power we might see with a storm surge or a tsunami. The force of the flowing water turns turbines that power generators to create electricity.

History

The timber industry in the U.S. used water wheels in the 1800s to power saws in lumberyards. Before long, it was understood that water falling from a great height could be used to turn turbines and generate electricity. The first hydroelectric plant in the U.S. was Niagara Falls in 1879 where the rush water of a naturally occurring waterfall was harnessed to product electricity.

Hydroelectric plants were constructed throughout the 1900s. Waterfalls were man made by building huge dams. The power plant consisted of a water reservoir surrounded by a man made dam.

Gates built into the dam could be opened and closed to regulate the amount of water flowing through. The energy produced by the turbines and generators below the dam was carried to commercial electric utility companies through large transmission lines that radiated out from the hydroelectric plant.

Limitations

For more than 100 years, the U.S. was first in the word in dam building and was the second largest producer of hydroelectric power in the world. Only Canada was generating more electricity from hydroelectric plants.

Building dams slowed by 1950 for two reasons. First, a hydroelectric plant has specific requirements for the height of the water reservoir. By the 1940s most of the sites meeting the topographical requirements had been developed.

Today there are more than 75,000 dams in the United States and about 2000 of those provide a little over 10% of the country's electricity. The remaining dams are for irrigation or flood control purposes rather than built as power plants. The second reason was the wide availability and low cost of fossil fuels at the time hydroelectric power was expanded throughout the country.

There are groups that proposed repurposing some of the non-power producing dams into hydroelectric plants. Clearly, these groups claim, this is one of the safest and most environmentally friendly methods of producing electricity. They believe converting some dams currently used for flood control or irrigation could increase the nation's power supply and reduce the dependence on fossil fuels.

Environmental Aspects

The environmental aspects may be clear but the effect on wildlife populations and fish species is not as clear-cut. When the earliest dams were built there was little planning or thought given to the effect dams might have on other species.

The weakness in this approach became evident quickly. Salmon swim upstream to spawn and were dying in record numbers as they could not make their way upstream when dams blocked their path. Today many dams have stepped water levels along the edge of the water flow. These steps provide a path up and over the dam for salmon and a safer journey downstream for other fish.

Reservoirs used for hydroelectric plants do not have to be naturally lakes but are often man made. If the height requirements can met for the waterfall required to produce power there are section so along most riverbeds where dams can easily be used to create a man made deep reservoir.

One advantage is the ability of such a plant to respect to changing demands on the electric grid. Solar power depends on being able to capture rays of the sun and this is possible only when the sunlight is falling on the solar panel. Wind energy is produced only when the wind is blowing and you can't increase the strength or speed of the wind.

The gates built into the dam of a hydroelectric plant can be quickly opened to increase energy production on demand. This increase may be due to higher temperature on hot afternoons or the growing population of a city.

There are many benefits to using hydroelectric energy. There is no water wasted and no runoff of harmful waste. Fossil fuels are not needed for the process. In fact, hydroelectric power plants convert about 90% of the power available into electricity. Fossil fuel plants have an efficiency rate of only about 50%.

Hydroelectricity is a financially sound method of energy production with no gases or runoff to harm the environment. Plants must be located in mountainous areas and cannot be safely constructed where fault lines are located in the earth. This eliminates many potentially useful areas where the height requirement can be met but the land may not be stable enough for dams to be built.

Summary

The danger of hydroelectric plants is in dam failure. Areas around the dams often will flood in rainy seasons and the dams can be used to regulate flood waters to some extent.

However, floods may be increased because of dams holding water in reservoirs. The great danger is in failure of a dam. The altitude that allows water to fall and power turbines can be a serious threat to those who live below the dam.