How Does Hydropower Work?: Hydropower: Eco20/20

How Does Hydropower Work?

Hydropower is the energy created by harnessing the power of water. Hydropower accounts for approximately ten to fifteen percent of the power used in the United States. It is the most efficient and most commonly applied form of green energy.

Water

Hydroelectric power plants use water to create electricity. Water is a renewable energy source. This is because of the water cycle. Water is constantly falling to the earth. When it gets warm, the water will evaporate back into the atmosphere. Once in the atmosphere, the water vapor will cool, causing it to become liquid again. This makes it too heavy for the atmosphere to hold up, and the water will fall back to the earth again as rain, snow, sleet or hail. Because the water cycle is an ongoing process, this makes water a great source of power.

Hydroelectric Power Plants

Hydroelectric power plants generally consist of a few basic parts. The penstocks, or pipes, control the flow of the water. This includes the velocity the water travels at and the height from which the water falls. The higher the waterfalls from, the greater the gravitational pull. If the water is moving at a high velocity when it hits a high fall, the velocity will be increased to an even higher rate of movement. Another major part of a hydroelectric power plant is the turbines, which are turned by the water. The generator is turned by the turbines and creates the energy. Each of these parts alone cannot produce electricity, but together they can produce enough energy to replace millions of barrels of oil.

Kinetic Energy

Any movement has the ability to create power because it already has energy: kinetic energy. Hydroelectric power plants simply turn the kinetic energy of a flow of water into a source of power. This is a very simple process. Water is moved through control channels or penstocks to ensure that the flow reaches the turbines at a high velocity. The higher the velocity, the more kinetic energy the flow is using, and the higher the amount of energy that can be created.

How Power is Created

Water is pushed through the penstocks at a high velocity. This causes the turbines to turn at a high speed. As the turbines turn, they in turn spin the generator. The generator then produces the electricity. The electricity is then stored. The stored and/or created electricity is then disbursed through power lines.

Electricity Generation

To generate electricity, the generator has to have two parts: the moveable part and the stationary part. The stationary part consists of a magnetic plate, while the spinning part consists of a rod surrounded by wire. As the turbines spin, the rod in the generator spins. As this happens, the magnets put a force on the electrons. As the electrons begin to move, this creates electricity. The number of electrons moving is the current. The current of the electricity is measured in amps.

Electricity: Still the Same

Whether electricity comes from coal, nuclear power, solar energy, wind turbines or water systems, the creation of electricity is basically the same. In all cases, movement of a source causes a generator to spin. This spinning in turn creates electricity. Even though the middle process is the same, however, using renewable energy sources such as water is cleaner and healthier than using nonrenewable resources.