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Energy and Our Future

(2) Do You Know How to Produce Electricity?

Electricity is the most common form of energy we use. The act of making electricity is called "power generation." Power generation can be roughly divided into four types:

  1. Thermal power generates electricity from steam made by burning oil and coal to boil water. As you may know, oil and coal are fossil fuels, so thermal power generation emits the greatest amount of carbon dioxide (CO2) of all types of generation. Also, older thermal power plants are more likely to leak harmful chemicals. Power companies try various things to reduce emissions of CO2 and other hazardous chemicals. For example, they use natural gas instead of fossil fuels. They also improve their power plants with new technologies.

  2. Hydropower generation uses the force or energy of falling water to rotate an electric generator. This form of power generation doesn't emit much CO2. However, building dams (strong walls that are built across rivers to stop the flow of water, especially to produce electricity) in the mountains damages the surrounding environment. Nowadays, "micro-hydropower" is a more popular form of hydropower. It generates electricity by making use of differences in elevation (water falling from a higher level to a lower level) in agricultural water and sewage pipes.

  3. Nuclear power generation makes electricity with the heat produced in uranium nuclear fission. It is said that the advantage of this method is that it emits no CO2 since nothing is burned during power generation.

    However, nuclear power also has some problems: concentrated uranium, the natural resource used in nuclear power, must be handled with the greatest of care. Also, no one really knows what to do with the waste that adversely affect the environment is left over. Furthermore, concerns about safety have grown worldwide ever since Japan experienced a major nuclear power plant accident in March 2011. In fact, most countries in the world are planning to either stop constructing new nuclear power stations, or decrease the number of plants.

  4. Compared to thermal and nuclear power generation, renewable power generation using unlimited natural resources (such as solar, wind, wave and tidal power, as well as biomass and geothermal) is rather new. Renewable energy still plays a small role in many countries. For instance, in Japan, renewable energy accounts for only 3 percent of all power generation. On the other hand, Denmark produces 30 percent of electricity from renewable energy such as wind. This percentage varies from country to country. How much renewable energy is used in your country?

How to Generate Electricity (Left: Hydropower Generation in Sweden, Right: Thermal Power Plant in Poland)