Many sustainable energy sources are being used to provide energy to people around the world. The motion of the wind and water are often used as sustainable energy sources as are the heat from geothermal vents and the light from the sun. Biofuels are also replacing the unsustainable fossil fuels that many people rely on for most of their energy needs. Engineers and scientists are developing technologies that can utilize previously untapped sustainable energy sources such as the waves and tides of the ocean.
Water has been used for centuries to supply energy. One of the first types of green energy power plant was the hydroelectric dam, some of which have been in continuous use for more than 100 years. Dams produce energy by allowing water to fall from a raised reservoir through a series of turbines than can collect and transmit the energy to a power plant. Engineers are also developing ways to use the motion of the tides and ocean waves to collect energy. Though sustainable energy sources that utilize the power of the ocean are still in the development stage, the vast amounts of energy in the ocean could make this an excellent source of energy in the future.
The sun is one of the most commonly used sustainable energy sources. Solar panels use photosensitive cells to collect and generate energy from solar radiation. The main drawback of this energy source is that power can only be collected when it is sunny out. Advancements in solar technology are allowing energy to be absorbed in partial sun and stored in batteries so that the energy can be used when the sun is not shining.
Geothermal and wind power are two sustainable energy sources that have been in use for a number of decades. Wind farms are quite common in many parts of the world where the wind can push blades that are connected to energy-gathering turbines. Geothermal power makes use of the heat that escapes from the earth's core as a source of power. It's major limitation is that it can only be used in areas are volcanically activity.
Another of the sustainable energy sources is biofuel. These fuels are being engineered to replace fossil fuels, which people are using faster than they can be replenished. Biofuels are extracted from plants, either as a byproduct of food crops or as the primary product from fuel crops.
