Huge energy resources originate in the oceans themselves and in the air above and land beneath them. Because offshore wind energy, wave energy, ocean current energy and offshore solar energy can help relieve the growing energy demands, the Energy Policy Act of 2005 authorized the Department of the Interior to grant leases and easements on the United States Outer Continental Shelf for the development and support of renewable energy resources.
Geothermal energy forms deep within the earth. The heat from hot springs rises close enough to the surface to drill and use it for heating water and buildings. You can generate electricity in cases where temperatures are not hot enough when you create steam from pressure that builds up by pumping cold water into the heated rock. One advantage of this energy source is that, unlike solar and wind energy, it does not depend on the weather.
Wind turbines convert wind energy into electricity. Air moving over the surface of the blades causes them to rotate, turning a rotor that drives a generator. Wind turbines automatically face the wind either by computer-controlled systems or mechanically driven devices. Wind speed is unpredictable, so wind speed and direction data are important pieces of information for you to ensure that your system operates at an efficient level.
Solar energy is available everywhere. It is a constant, unrestricted source of energy that directly heats buildings and hot water. It can also light homes and other buildings, generate electricity and cool the air. You can decrease your energy bills and increase your hot water supply; at the same time you can reduce household emissions responsible for global warming and acid rain.