What is hydro power ?

Water has huge power. We can feel this one our bodies when we cross a sea or river. The power we get from water is called hydro-power. Hydro-power has been one of the first force used by human beings to simplify their work. For example, tasks such as turning wheat into flour, processing wood to make paper, making textile, and turning hard metals into various interesting shapes, which were difficult to do earlier, have been made easy by using hydro-power. Dams are made by erecting huge walls in water to generate electricity. Even today there are ferries and boats without engines that use the force of flowing water. Even tides in the oceans can be used to produce energy.

How does a watermill work ?

A watermill uses a large wooden or metal wheel to generate power. It consists of many small blades, over which the flowing water of a stream run; this wheel is called the 'water wheel'. The flowing water rotates the wheel. This rotational movement produces electricity when connected to a generator. Although mills were used to generate hydro power in earlier times in all countries, people in the underdeveloped countries uses them even today. Electricity produced in such a manner is pollution free and does not harm our environment.

How is electricity generated by using a dam ?

Dam walls are mostly made of a material called concrete. These dams retain a large amount of water. The retained water puts very high pressure on the lowermost layers of water. If the water in these lowermost layers is diverted, it flows at a very high speed, and hence a high energy is produced with the hep of a device called turbine. In the turbine, the energy is sued to generate  electricity. The type of energy we can reuse since it is unlimited in nature is called renewable energy, such as the energy from the sun, wind, and water. Hydro-power is currently the only renewable energy that is used to a large extent. In Austria, approximately half of the electricity is generated by hydro-power, while in Norway all the electricity is generated by hydro-power

(all the image from google image credit goes to google)

HOW IS ELECTRICITY GENERATED FROM SOLAR ENERGY?

The sun is the source of all energy either in the form of fossil fuels or wood. After all, these substance have been made from the energy of  the sun and have stored its energy. However, the heat of the sun can be used directly in the form of solar energy. Solar cells and giant solar plants are used for generating electricity. It has been estimated that the solar energy reaching the Earth's surface in one year is double than we will ever receive from all the Earth's resources of coal, oil, natural gas, and uranium together.


HOW CAN WE CAPTURE THE HEAT ENERGY OF THE SUN?

The easiest way to capture the heat energy of the sun is to use it to heat water. In countries with regular supply of abundant sunlight, the roofs of the houses have tanks with water that gets heated by the sunlight. 'Solar houses' can now be seen in various countries across the world. Solar collectors are placed on the roofs of these houses which collect heat from the sunlight. This energy is used to heat water, which in turn produces steam which drives a turbine connected to an electrical generator produce electricity.