In the 21st century, electricity is a feature of life that much of the world takes for granted. However, electricity is still a relatively new invention, having only come into widespread use around a century ago.

Today, interest in different ways to generate electricity is growing, as some experts predict that traditional non-renewable sources will be depleted within the next 100 years. Here’s a quick guide to the different ways in which electricity is generated in 2012.

Generating power with fossil fuels

The main method of power generation today is the burning of fossil fuels, like coal, gas and oil. These materials need to be dug out, drilled or extracted from the earth and they are called ‘fossil fuels’ because they contain the remains of ancient plants and animals. While oil and gas can be burned directly, coal needs to be crushed and then burned to be effective.

The electricity generation process starts by burning one of these fuels (the popularity of each varies from country to country). As the fossil fuels burn, they heat water, which creates steam. This steam then moves generator turbines within the power plant. As the turbines turn, they send an electric current through a piece of wire, which is in turn connected to a series of transformers. As the current travels through transformers, its voltage is slowly lowered and finally enters homes and commercial buildings through a service box.

Power generation from renewable sources

Although fossil fuels remain the primary source of power generation, renewable sources like tidal, nuclear and geothermal power are slowly gaining ground. One popular source of renewable power generation is wind energy. To harness the power of wind, wind turbines have to be built. Like windmills, wind turbines feature three or four blades and may take the form of huge structures dotting the countryside (‘wind farms’) or small models that sit on top of domestic buildings. When warm air rises, more air rushes in to fill the gaps left behind. This creates the gusts we call wind. When these gusts catch the blade of a wind turbine propeller, it starts to move round. This movement turns a generator, which produces electricity.

Solar energy is another form of renewable power generation. Harnessing solar power requires the installation of photovoltaic (‘PV’) cells, which convert light directly into electricity. PV panels may be expensive and the unreliability of solar energy in all but the sunniest climates means that they are still unable to provide a complete replacement to power created by the burning of fossil fuels. However, they are useful for heating certain aspects of a household – for instance, a boiler or furnace.