Learn About Alternative Energy for Kids
We need energy to power buildings, cars and airplanes. Nonrenewable energy is a type of energy we will run out of at some point. Oil, coal and natural gas are types of nonrenewable energy. Oil is used to make the gasoline we put into cars. Coal and oil are used to generate the electricity that's used to power homes and businesses. Someday all of the world's oil will run out, so we need to find different ways to power cars and create electricity. Burning coal and oil also creates a lot of air pollution.
Renewable energy is energy we can make over and over again. It is called clean energy because it doesn't pollute the air and contribute to global warming. Renewable energy includes wind power, solar power, hydro power, biomass energy and geothermal energy.
When wind turns the blades of a windmill, it spins a turbine inside a generator. This creates electricity. To make enough electricity for large populations, wind farms are needed. Wind farms are placed in very windy areas. They have dozens to hundreds of windmills. Onshore wind farms are located on land. They're often in hilly or mountainous area where there's more wind. Offshore wind farms are located in bodies of water like seas and oceans.
The word solar means sun. Solar power uses the sun’s energy to create electricity. Large solar panels are needed to capture and store the sun’s energy. Using the sun to make electricity is called photovoltaics. Solar energy doesn't create any pollution and when placed on top of buildings doesn't have any impact on the environment.
The amount of solar energy the earth receives every day is many times greater than the total amount of energy used around the world. However, capturing this energy is very expensive, so solar power isn’t widely used yet. Solar power stations are often called solar parks or solar farms. This is because they used large open areas of land filled with huge solar panels.
Hydro means water. Hydro power creates electricity using the power of moving water. Moving water can spin a wheel or blade that spins a turbine inside a generator to make electricity. Dams are often built to create electricity. The force of water moving through a dam spins the blades of huge turbines. A hydroelectric dam can create enough energy to power more than a million homes.
Biomass energy uses leftover materials from paper mills, sawmills and farms to create electricity. These materials include wood, paper, cornstalks and corn cobs. Trash and fast growing trees can also be used. Some farmers actually grow crops for power companies. These energy crops and other biomass can be burned to create steam to power generators.
Geo means earth. Thermal means heat. Geothermal energy uses underground hot water reservoirs to power electric generators. Steam from the reservoirs spins turbines to create electricity. The Geysers in Northern California is the largest geothermal power plant in the United States. It creates enough electricity to power about 725,000 homes.