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Green electricity
Sources of energy which are unlimited and environmentally friendly are called __________.
It’s an ordinary morning in the city. Bright shop signs turn on, trams run across the roads, and street lights help control the traffic. People in the offices make phone calls, work on their computers, and make coffee. A city like this needs a lot of electricity! But where does it all come from?
In many places on earth, energy is produced from fossil fuels such as coal, oil, and natural gas. People have used these for so many years, that the technology to produce electricity from fossil fuels is very advanced. Fossil fuels are easy to transport, which makes them simple to use all over the world. However, fossil fuels are harmful for the environment, because they cause air pollution and increase carbon dioxide emissions, which lead to global warming. The amounts of coal, oil, and natural gas on Earth are limited and we are going to run out of them within the next fifty to one hundred years.
We need different, more sustainable ways to produce electricity. Sources of energy which are unlimited and do not destroy nature are called RENEWABLE. The sun is an example of a renewable energy source. It continuously produces SOLAR ENERGY in the form of radiation, light and heat. Using solar panels, we can capture sunlight and transform it into electricity.
Blowing wind is an unlimited source of energy too! We can capture the energy from the wind - or WIND POWER - using wind turbines. When a turbine’s blades move, the parts of the mechanisms inside the turbine spin. This drives the generator which transforms this movement into electrical energy. The movement of water, such as waves or flowing rivers, is a source of HYDROPOWER.
When the water moves, it spins a turbine in a HYDROPOWER PLANT. The turbine drives a generator which produces electricity. One more renewable source of energy comes from organic waste and living organisms. It is called BIOMASS. Solid biomass, for example wood, can be burned directly to produce heat and steam which powers a generator.
We can also turn biomass into fuels such as BIOGAS. Biogas can be used to produce electricity in a biogas power plant. Why is this electricity called green? Green means environmentally friendly. Unlike fossil fuels, wind power, solar energy, hydropower, and biomass do not increase carbon dioxide emissions which cause global warming.
They also do not cause as much air pollution. To produce electricity, they use resources which are unlimited, So they are more sustainable than fossil fuels. However, green electricity has a few drawbacks too. It is a relatively new idea, so the technology is not as advanced. This makes green electricity less efficient and often more expensive.
Some kinds of green energy have limitations related to weather conditions and geographical location. For example, it is difficult to use solar energy where there is little sunlight. It is also complicated to store and transport green energy from places where it can be produced to places that need it, such as cities. Despite these difficulties and limitations, we are coming up with new, better ways to produce energy using the sun, wind, water and biomass. Hopefully all the electricity we use will soon be green.