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How electricity is generated?

Generation is the process of producing electricity from various sources, e.g. coal, oil, nuclear, gas and wind to produce electricity from power stations. A turbine takes a movement of air, steam or water and turns it into energy which then feeds directly into the generator.

A simple generator that many people will have encountered is the dynamo on a bicycle, which is turned directly from the wheel rim. This converts the movement of the wheel into electricity to power the lights.

Steam-generated power is produced and driven through the turbines, which turn the generator, producing electricity. This leads to two questions:

  1. How do you make the steam?
  2. What do you do with the steam afterwards?

Steam is made by heating up water. This is done in a boiler and can be done by burning just about anything. Coal, oil and gas are the main fuels for power stations. Unfortunately, burning fuel produces large quantities of carbon dioxide. This seemingly harmless gas has been blamed for the greenhouse effect which appears to be heating up the world.

Another way to make steam is to heat water using a lump of active uranium. A nuclear reaction in the uranium generates a lot of heat which boils the water. Nuclear stations produce no carbon dioxide, but they do produce small amounts of extremely hazardous waste instead.

Hydroelectric, here the turbine is driven by moving water rather than moving air. The way to get the most power out of water is to dam the river and collect it in a lake. All the water from the lake is then dropped down through a narrow pipe and through the turbines. The water turns the turbine, the turbine turns the generator and the generator makes the electricity.

Wind generators are probably the easiest type of power station to understand. The turbine consists of the rotating blades. The wind turns the blades, these drive the generator. Wind generators are becoming more popular because they are clean and damage the environment very little.

Theme

Electricity is made a number of ways.

Aims

  1. Understand how electricity is generated
  2. Start thinking about turbines and generators

Suggested Activities