Renewable energy feeds power grids around the world, generating electricity without the environmental pollution created by coal, oil and natural gas.
So what is a renewable resource and how is it converted into electricity?
Renewable energy resources are all around us. Sun, wind, water and, yes, garbage are rich and inexhaustible sources of clean electricity and fuels. The trick is to build the infrastructure globally to take full advantage of these natural assets.
5 dominant renewable energy sources
Biomass is organic material, meaning it comes from plants and animals. Wood and wood waste have long been burned for fuel and electricity. But now there are better ways to extract energy from wood, crops and agricultural waste in a way that doesn’t pollute. Transportation fuels are made from crops such as corn and sugar cane, which are fermented to produce ethanol. Landfill garbage and animal manure can yield biogas and liquid fuels.
Geothermal energy is heat from the Earth’s core that may be tapped directly for hot water or for steam to run electricity-generating turbines. Regions with volcanic activity have the greatest access to geothermal resources. But the stable temperatures near the surface of the Earth may be used to heat and cool buildings anywhere.
Hydropower is a major source of electricity generation wherever there are rivers and streams. The force of moving water activates turbines that generate electricity. Water dammed in reservoirs is released to run turbines when needed. Flowing rivers and waterfalls also can propel turbines. But hydropower is dependent on rainfall, and droughts can hamper energy generation from water sources.
Solar energy comes from the sun. It can heat water and buildings or power turbines that generate electricity. Photovoltaic, or solar, cells convert sunlight into electricity directly, and may be used on a small or large scale. One solar panel on a rooftop can run a couple of lights and a laptop computer. Large-scale solar power installations provide electricity to the power grid.
Wind is created when the heat of the sun warms the Earth’s surface. Breezes are variable, and some regions are windier than others. Wind moves the blades of turbines, generating electricity. Wind energy has been used for thousands of years to pump water from wells. Today it is, increasingly, a mainstream electricity source.
What kind of energy do you use?