Types of Energy
The sun is the natural source of light and heat. The energy obtained from the sun is called solar energy. Plants prepare their food using sunlight. The Sun is the main source of heat energy nowadays, solar heaters are increasingly used to heat water for various purposes at homes and industries. Since solar cookers are smoke free and less expensive, using them for cooking is easy and ecofriendly too. Sun light canbe transformed in to electricity through solar cells. They are used for lighting purposes.
What do we do when it is hot? We do not like to be out in the hot sun. We go to the shade of trees or inside the house. We open the doors and windows to let in cool air. We also put on the fan. We like to drink plenty of water. We also enjoy cold drinks and ice cream. We like to wear light colored clothes. We also prefer thin cotton clothes. What do we do when it is cold? We like to sit outside in the sun to get heat. We close our doors and windows when it gets very cold. We like to drink something that is hot, like hot tea or coffee. We wear warm woolen clothes. In very cold places, we like to sit near the fire-place.
Wind is a form of energy. Wind energy rotates the wheels of wind mills thus generating mechanical energy. This energy is used for various activities. For centuries, wind has been used for the sailing of ships. Even the slow moving wind has energy.
Animal dung, plant residue and agricultural wastes on decaying in the absence of air produce a gas called biogas. Biogas is used for cooking and for other domestic purposes. The energy produced by the biogas can be converted into electrical energy.
Running water is another source of energy. Water is stored in dams built across the rivers. By making storedwater run down through pipes in to a turbine, electricity can be produced. Solar energy, water energy, wind energy and bio energy can be used for a long time. Nowadays these alternate sources of energy are used in place of fuel energy and electric energy. With this, the use of fuels like petroleum and coal could be minimized.Petrol and diesel, cooking gas and coal should be used economically. Efforts should be made for alternate ways of getting energy.