Renewable Energy Resources: Part 1
Renewable energy resources are being developed because we are running out of fossil fuels at an exponential rate.
The wind is produced as a result of giant convection currents in the Earth’s atmosphere, which are driven by heat energy from the sun. Wind turbines use the wind to drive turbines directly. The blades are connected to a housing, which contains gears linked to a generator. As the wind blows, it transfers some of its kinetic energy to the blades, which turn and drive the generator. The advantages are that there are no fuel costs and no harmful pollutant gases are produced. However, they depend on wind, if there is no wind, there’s no electricity.
Like the wind, water can be used to drive turbines directly. Wave machines use the kinetic energy in this movement to drive electricity generators. Another way of using the water is to build a tidal barrage over a river estuary to make use of the kinetic energy in the moving water. The barrage contains electricity generators, which are driven by the water rushing through tubes in the barrage. Hydroelectric power stations are dams built across a river valley. The water high up behind the dam contains gravitational potential energy. This is transferred to kinetic energy as the water rushes down through tubes inside the dam. The moving water drives electrical generators, which may be built inside the dam. Water produced energy is good because no harmful polluting gases are produced and tidal barrages and hydroelectric power stations are very reliable and can be easily switched on. However, tidal barrages destroy the habitat of estuary species and hydroelectricity dams flood farmland and push people from their homes.