Alternative energy and its sources
What are the main sources of alternative energy?
Alternative energy is all around us! It was used long before fossil fuels became standard sources of energy(2), and it’s returning to standard use in many traditional and innovative forms. Here are some of today’s most common sources of alternative energy:
- Bioenergy: Named from “bios,” the Greek word for “life,” bioenergy generates electricity through burning organic materials such as wood, charcoal, manure(3), and crops such as corn and soy.(4) It’s a centuries-old way to harness the sun’s chemical energy that’s stored in these sources.(5) While processing this biomass does result in greenhouse gas emissions(6), the environmental impact is lower than fossil fuels produce, and it also tends to cost less.(7)
- Geothermal: Also derived from Greek roots, this time from words meaning “earth” and “heat,” geothermal energy leverages underground reservoirs of hot water and steam to generate power.(8) The technology has been dependably delivering energy for more than a century.(9) It’s most often seen in areas with plentiful volcanos such as Iceland, where it produces more than 25 percent of the country’s electricity.(10)
- Hydropower: Moving water isn’t just powerfully beautiful – it’s also been a powerful source of energy worldwide for thousands of years.(11) Hydropower captures the energy of a controlled flow of water from a reservoir or river(12) to drive a turbine that generates electricity.(13) Nearly three-quarters of all renewable energy currently comes from hydropower.(14) The water reserves can also be used to provide water for drinking and irrigation. Though there are typically no concerns about their carbon footprint, hydropower operations can negatively affect surrounding ecosystems.(15)