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What Is Renewable Energy?
Renewable energy is sustainable energy derived from renewable sources—natural resources that replenish on their own—like wind, sunlight, and rain. Renewable energy sources provide more eco-friendly ways to harvest power and can be an alternative to costly and damaging energy practices, like mining or burning fossil fuels.
What Are the Benefits of Renewable Energy?
Green power has less environmental impact than traditional energy sources like coal, oil, and natural gas. Here are the main benefits of renewable energy:
- Fewer greenhouse gas emissions. Renewable resources reduce our carbon footprint by emitting fewer pollutants and carbon dioxide emissions into the atmosphere. Fewer CO2 emissions and other toxic outputs can help slow climate change’s negative impact on the environment.
- More reliable sources of energy. Renewable energy resources diversify the energy supply, making us less reliant on toxic chemicals or pollutants to provide us with power. Unlike fossil fuels, renewable energies are infinite and are not in immediate danger of exhaustion. Using resources like the wind or the sun does not reduce the amount of wind and sunlight available for others, which means power can be harvested without destabilizing the environment.
- Less maintenance. Most renewable energy technologies don’t rely on fossil fuel-powered generators to operate their facilities and require little more than occasional inspections. A more straightforward setup means fewer moving parts, which means that renewable energy facilities can have lower operating costs and fewer maintenance needs than traditional facilities.
6 Types of Renewable Energy
New forms of renewable energy are always being tested and considered. Some of the current types of renewable energy are:
- Solar energy: Solar panels capture the sun’s energy, harnessing sunlight as a renewable power source via photovoltaics (PV). Solar panels can capture 15 to 20 percent of solar energy and produce approximately 300 to 400 watts of electricity. Current studies show that solar power has zero emissions and environmental impact and can help reduce energy costs.
- Wind energy: Wind turbines use wind power to generate electricity. Turbines are usually painted a neutral color like white or light grey to help blend in better with any natural surroundings and reflect direct sunlight that can cause cracking or overheating. Each turbine has three blades to make it easier to maintain spinning momentum and produces thousands of megawatts of electricity per year. Wind farms refer to a group of turbines located in close proximity. Wind farms can function like a power plant, generating electricity and sending it to a grid.
- Hydroelectric power: Hydroelectricity, or hydropower, forms when the flow of water spins a turbine, generating electricity. A hydraulic turbine converts the kinetic energy of moving water (from a large dam or water power plant) into mechanical energy. A generator then converts this mechanical energy into electricity. Hydroelectric power has high energy efficiency—some facilities are able to convert at least 90 percent of their energy into electricity, where most fossil fuel plants are around only half as efficient.
- Geothermal energy: Geothermal power plants use the heat and steam generated by the Earth’s core to produce electricity. Wells are dug about one to two miles deep, which pumps hot water to the Earth’s surface. The change in pressure turns the pumped water into steam, which moves a turbine for electricity generation. Geothermal heat energy can provide hot water, heating, and other electric utilities to homes and buildings and energy for industrial processes like laundering, distillation, and sterilization.
- Biomass: Biomass energy is derived from plant materials, animals, agricultural waste, manure, and other organic matter. When these organic materials—also known as feedstocks—no longer have any value, they can be burned to produce energy for heating and electrical energy. Certain forms of biomass, like waste, are considered renewable because humans will never stop producing waste. However, if more biomass feedstocks are used than replenished, biomass can become a nonrenewable resource.
- Hydrogen: Hydrogen is an abundant, natural element that can be harnessed to create electricity. Although most hydrogen is produced by fossil fuels like natural gas, there are ways to produce hydrogen using renewable energies like biomass and solar power. Hydrogen fuel cells cleanly produce power that can provide electricity to buildings like hospitals and data centers or power motor vehicles with potentially few to zero emissions.
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