What Are Some Mechanical Energy Sources?

Ocean waves are just one type of mechanical energy.

The two main types of mechanical energy are motion and stored. Motion energy is known as kinetic energy, and is the energy an object has because it is moving. Stored energy is when an object has energy that is ready to be expended. Both of these types of mechanical energy are also known as potential energy, because mechanical energy can be changed into other types of energy.

Ocean Wave Energy

One way to take advantage of the energy that is contained in ocean waves is with a wave power energy converter. These devices may float on the water, similar to a large ship, or they can be attached to the sea floor -- completely submerged. This technology is being used in Europe with some success. In the United States, the California Energy Commission has been studying the feasibility of similar projects. They have found that every mile of California coastline could produce between 7 and 17 megawatts of energy. Ocean wave energy is a form of kinetic or motion energy.

Ocean Tidal Energy

Tidal energy -- a form of kinetic energy -- is harvested when the tides roll onto the shore. The water is then trapped in reservoirs located behind dams. When the tides drop and the water recedes away from the dam, water in the reservoir is released. The action of the water flowing through the dam is converted into electrical energy. The energy conversion at a tidal plant is the same as a standard hydroelectric plant.

Hydroelectric Power

Also a kinetic energy source, electrical energy is captured from water that is moving downhill. Water is used to turn a turbine generator, which converts the energy into electricity. Often, dams are constructed upriver of hydroelectric plants so that the plants can be sure of a constant flow of water. For instance, during a particularly rainy season, the excess water would get trapped behind the dam in a reservoir. Should a dry season come later, there would still be enough water to maintain a consistent flow through the power plant.

Springs and Slingshots

Springs and slingshots are just a couple of examples of stored mechanical energy. Clocks and watches that are wound up use stored energy. The clock works because it has been wound, and the release of tension on the winding spring is what gives the energy for the clock to work. A slingshot also uses stored energy. When the rubber straps of a slingshot are pulled back, they contain stored energy. When the straps are released, so is the energy.

References

• Renewable Energy World: Ocean Energy
• California Energy Commission: Ocean Energy
• Encyclopedia of Earth: Renewable Energy
• Physics Classroom: Mechanical Energy