The Earth is getting warmer because people are adding heat-trapping gases to the atmosphere, mainly by burning fossil fuels. These gases are called greenhouse gases. Warmer temperatures are causing other changes around the world, such as melting glaciers and stronger storms. These changes are happening because the Earth's air, water, and land are all linked to the climate
Geothermal power plants, which use heat from deep inside the Earth to generate steam to make electricity.
Geothermal heat pumps, which tap into heat close to the Earth's surface to heat water or provide heat for buildings.
At a geothermal power plant, wells are drilled 1 or 2 miles deep into the Earth to pump steam or hot water to the surface.
hot springs, geysers, or volcanic activity, because these are places where the Earth is particularly hot just below the surface.
Hot water is pumped from deep underground through a well under high pressure.
When the water reaches the surface, the pressure is dropped, which causes the water to turn into steam.
The steam spins a turbine, which is connected to a generator that produces electricity.
The steam cools off in a cooling tower and condenses back to water.
The cooled water is pumped back into the Earth to begin the process again.
Geothermal heat pumps can do all sorts of things—from heating and cooling homes to warming swimming pools.
heat by pumping water or a refrigerant (a special type of fluid) through pipes just below the Earth's surface, where the temperature is a constant 50 to 60°F.
When we get electricity from renewable energy sources like wind and solar power, we avoid the carbon dioxide emissions that would have come from burning fossil fuels like coal, oil, or natural gas.
Waves are caused by the wind blowing over the surface of the ocean
. Ocean waves contain tremendous energy potential. Wave power devices extract energy from the surface motion of ocean waves or from pressure fluctuations below the surface.
Hazardous chemicals are used in the manufacture of solar cells, creating environmental considerations in their manufacture and, in some cases, in their eventual disposal. Solar cell manufacturers minimize their use of these chemicals, recycle them when possible, and release a minimum of pollutants to the environment.