Every year on April 22, people around the world celebrate Earth Day with events that promote environmental health and sustainability. And since it was first observed in 1970, Earth Day has grown from a once-a-year holiday into an international movement that strives to ensure a healthy environment for our children and generations beyond.
Solar: Solar energy, or solar power, which is provided by the sun, can be passive, such as maximizing south-facing windows to heat rooms, or photovoltaic (pv), using special equipment to collect the sun's energy and transform it into electricity.
Wind: Harnessing the power of wind to produce electricity is perhaps the fastest growing renewable energy source in the world. Wind power is clean. Wind energy is been used for centuries in many parts of the world, and in areas where high winds are prevalent, says Duffy, wind power can actually cost less than electricity produced by burning fossil fuels.
Geothermal: Geothermal energy comes from heat deep in the earth's crust which rises toward the surface producing hot water and steam. In areas where good geothermal resources exist, including many parts of the western United States, the heated groundwater can be used directly to heat homes and other buildings, or it can be used in power plants to produce electricity.
