Global electricity mix 2021, by energy source

Fossil fuels remain the greatest source of electricity generation worldwide. In 2021, coal accounted for roughly 36.5 percent of the global power mix, while natural gas followed with a 22 percent share. Fossil fuel use notwithstanding, the share of renewables in global electricity has seen a more pronounced year-on-year growth in recent years, following increased efforts by governments to combat global warming and a decrease in levelized costs. By 2040, projections show renewables to have surpassed fossil fuels as the main power source.

How is electricity generated?

An electricity generator converts a form of energy into electricity through mechanical energy. One of the most common generators uses an electromagnet, which produces several small currents as it rotates. These smaller currents combine to form a larger current that becomes the electricity for consumers to use. Commonly, electricity generation is elicited through power plants that use a turbine or other machinery to drive the generators. Different energy sources require different methods to harness their energy.

Fossil fuels like coal and natural gas are burned, nuclear power relies on nuclear fission, and geothermal power plants utilize heat in areas near tectonic plate boundaries; all of these examples constitute thermal energy, which is fed through a steam turbine to generate electricity. Other types of turbines include hydroelectric turbines and wind turbines. Energy sources, such as solar photovoltaic cells, do not depend on turbines and can convert sunlight directly into electricity through collectors.

China is the largest electricity consumer in the world, requiring nearly 6,900 terawatt hours of electricity every year.