The power of water is abundant—approximately 73 percent of all renewable energy according to the Energy Information Administration (EIA). Hydropower is generated using the mechanical energy of flowing water by forcing it through piping called a penstock, which then turns a generator in order to produce electricity. Water power also consists of wave and tidal energy, which are both in the infant stage of research, as scientists try to discover how to harness the energy produced from movement of the ocean. The Hoover Dam is the largest hydropower system in the U.S.Solar cells made from silicon absorb the sun's radiation, also called photovoltaic cells. The photovoltaic process involves the movement and displacement of electrons to absorb the sun's radiation and create electricity, but there are also solar systems that use large-scale mirrors to heat water, or produce high temperatures and generate steam, which is used to turn a generator.Wind power is a very simple process.
A wind turbine converts the kinetic energy (motion) of wind into mechanical energy that is used to generate electricity. The energy is fed through a generator, converted a second time into electrical energy, then fed into the grid to be transmitted to a power station. Wind power is abundant in California and Texas, with the two largest wind farms in the world residing in West Texas. Wind is unique because it carries incentives for farmers to give parcels of land for building wind turbines, and has the most potential as far as widespread adoption due to the large areas of land with consistent wind available to harness.The process involves trapping heat underground, then building energy that rises near the surface in the form of heat. When this heat naturally creates hot water or steam, it is harnessed and then used to turn a steam turbine to generate electricity. The Italians were the first to use geothermal energy for commercial purposes in the early 1900s.Biomass is a very versatile form of renewable energy. Biomass power plants burn biomass fuel in boilers to heat water and turn a steam turbine to create electricity. Biomass fuel is everything from wood to landfill trash, which is currently being used to convert into methane for the production of dry natural gas. Agricultural research is seeing unique results, including dairy farms in Texas converting cow manure into energy.