Renewable Energy: fun facts and quiz

Renewable energy comes from sources that refill naturally, like sunlight, wind, flowing water and the Earth’s heat. Coal, oil and gas took millions of years to form.

Key fact
Renewables make about 30% of the world’s electricity.

Solar panels turn sunlight straight into electricity. Their price fell by around 90% during the 2010s, making solar one of the cheapest sources of power.

Key fact
Solar panels still work on cloudy days, just less well.

Wind turbines use the wind to spin their blades, which turn a generator. Some offshore turbines have blades over 100 metres long.

Key fact
Turbines usually shut down in very strong winds, to protect themselves.

Hydropower uses falling or flowing water to spin turbines. It’s the biggest renewable source of electricity worldwide.

Key fact
China’s Three Gorges Dam is the world’s largest power station.

Geothermal energy uses heat from deep underground. Iceland gets about a quarter of its electricity from it, and heats most of its homes with it.

Key fact
About 9 in 10 homes in Iceland are heated with geothermal water.

The sun sets and the wind drops, so clean power needs storing. Big batteries and pumped hydro, which pumps water uphill to release later, fill the gaps.

Key fact
Pumped hydro is by far the most common large-scale energy storage.

Burning coal, oil and gas releases carbon dioxide, which warms the planet. Wind, solar and hydro produce almost none while they run.

Key fact
Coal is the most carbon-heavy way to make electricity.