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Electricity GenerationReview: Why is electricity important?

- We use electricity in many ways in our daily life:o Lightingo TV/Computer/Cell phoneo Home appliances: refrigerator/microwave/washer and dryer/Coffee machine

- Generating electricity has an environmental footprint

Electricity generation:

1-Spinning a turbine

Electricity Spinning a fan

Spinning a fan Electricity

1-1) Coal power plant

1-2) Hydro power plant- "Hydro" means "water" in Greek - so "hydro power" is made from water.- It might sound odd that we can use water to make electricity because they're a dangerous

combination, right? Actually, the water never comes in contact with the electricity. The water flowing down a river is used to spin the turbines inside the generator.

1-3) Wind power plant- Using the wind to create electricity has been around for a long time, you've probably seen

windmills on farms. When the wind turns the blades of a windmill, it spins a turbine inside a small generator to produce electricity, just like a big coal power plant.

- A windmill on a farm can make only a small amount of electricity, enough to power a few farm machines. To make enough electricity to serve lots of people, power companies build "wind farms" with dozens wind turbines.

2-Solar photovoltaic (PV)- Solar energy is obtained from sunlight.- Solar energy has been used by humans for a long time for uses such as heating, cooking

food, removing salt from seawater and drying clothes.- These days it is also used to create electricity. As technology has improved, solar power

costs have decreased and it has become a more viable alternative, competing with energy sources such as coal and oil.

- While solar power is becoming more efficient, it only provides a small fraction of the world’s energy supply.

- Solar cells convert light energy into electricity.- Solar cells are also called photovoltaic cells.- Solar cells can be used to power portable devices such as calculators.- Large numbers of solar cells are put together to create solar panels.- The largest solar power plant in the world is found in the Mojave Desert, USA