Nowadays, most energy we use is non-renewable energy produced by fossil fuels. Fossil fuels are hydrocarbon deposit such as petroleum, coal, or natural gas and are formed by action heat of the earth’s core and pressure from rock and soil on the remains of dead plant and animal over millions and millions of year . We cannot produce the fossil fuels in a short period of time. That is a reason why the world supply of fossil fuels is limited, eventually the world will run out of it and it will even be more costly to get the remaining supply of those fossil fuels. Moreover, the production of non-renewable energy from the fossil fuels causes air, water and soil pollution and also produces greenhouse gases that contribute to global warming. Therefore, in order to solve the energy sufficiency and pollution problems, we should seriously do research and develop renewable energy.
Renewable energy is energy that is produced by sources that we are able to reproduce in the short period of time and produce a little or no pollution or greenhouse gases from the production method. There are many kinds of renewable energy such as:
1. Solar energy is energy that comes from the sun. The Solar panels on the roofs of houses, building and other establishment are use to store the solar energy. The sun’s energy harnessed by the panels runs generators which provide electricity.
2. Geothermal energy is energy that comes from the heat inside the earth. It is a technology that involves boring a hole into the ground to take the heat from the earth’s crust. The heat that comes off is used to heat water and make steam to power generators to make electricity.
3. Biomass energy is energy that from the plant and trees. There is a wide variety of biomass energy sources, including tree and grass crops, forestry, agricultural, and urban wastes. It is the oldest source of renewable energy known to humans, used since our ancestors learned the secret of fire .
4. Hydro energy is energy that comes from water. Hydro energy can be obtained by using many methods of capture. The most common method of using energy from water is a hydroelectric dam, where water coming down through an area causes turbines to rotate and the energy is captured to run a generator .
5. Wind energy is energy that comes from wind. It captured by wind turbines and used to generate electricity. The costs of wind energy are going down as mass manufacture of turbines becomes more accepted.