Hydropower, or Hydroelectric power, is the harnessing of the energy of moving water to create electricity. The force of falling water turns a wheel, or turbine. This creates electricity by turning a generator.
Hydropower, or Hydroelectric power, contains 6 major parts.
This controls flow of water and increases elevation for a higher water wall. Moving water, by power of gravity, is created by making a reservoir above the turbines. This dam contains floodgates which it can open and close to vary the amount of water entering the penstock.
A penstock is a large pipe that channels water from the dam to the turbines.
These are turned by the force of the moving water pushing against large blades attached to a cylinder.
These generators are connected to the turbines. As the turbines rotate, they move giant magnets around coiled copper wire to get the electrons moving, thus creating electricity.
These convert the electricity from AC to DC (alternating current to direct current). This changes the form of electricity to one that we can use.
These transport the energy into your home or business.
Another types of hydroplant is a pumped storage system. This system is used to store energy when it is not needed.
How it worksA pumped storage system pumps water through a pipe from a lower reservoir (called a "tailpond" or "afterbay") to an upper reservoir (called a "headpond" or "forebay"). This allows electricity made a night, when not many people want it, to move the water up to the headpond, so that it can be sent down to the tailpond when additional power is needed. This water, then it goes down, passes through a turbine, generator, transformer, and to transmission lines just like in a hydropower plant.
Hydropower can be used in any one of three power usage capacities: Primary Source, Reserve Source, or Start Up Source
This is the main energy supplier for a city or town, requiring a large body of water with a very high base flow of water and a lot of rain.
This acts as a secondary source of power when extra power is needed during peak hours (from 11:30 to 3:00). Usually it supports a nuclear power plant or a coal power plant. This is the most common type of hydropower source.
Because a hydropower plant can start without any outside energy, also called a black start, it can be used to start up other power plants, most of which require energy for lights, electronic monitering equipment, etc.
There are thousands of sites all over the world that would be suitable for hydropower plants. With the great increase in power need as we approach the new millenium, we will need more clean energy sources.
Hydropower is a clean source of energy. There are no problems with air pollution, chemical runoff, toxic waste or the like.
Hydropower plants also create recreation areas and animal habitat. Because of the change in water location, wide areas after the dam become great for water edge species of animals. And the large reservoir is good for many types of large fish. Boating areas are created in the reservoir too, as well as bird watching sites downstream of the dam.
Some problems may still occur though., but through careful planning these can be eliminated almost completely.
Now that you have finished learning about hydroelectric power, you may wish to test your understanding by taking the online test.