Renewable Energy

Renewable energy, often referred to as clean energy, comes frenewable Energyrom natural sources or processes that are constantly replenished. For example, sunlight or wind keep shining and blowing, even if their availability depends on time and weather.
While renewable energy is often thought of as a new technology, harnessing nature’s power has long been used for heating, transportation, lighting, and more. Wind has powered boats to sail the seas and windmills to grind grain. The sun has provided warmth during the day and helped kindle fires to last into the evening. But over the past 500 years or so, humans increasingly turned to cheaper, dirtier energy sources such as coal and fracked gas.

Renewable Energy: Solar Energy

Solar, or photovoltaic (PV), cells are made from silicon or other materials that transform sunlight directly into electricity. Distributed solar systems generate electricity locally for homes and businesses, either through rooftop panels or community projects that power entire neighborhoods. Solar farms can generate power for thousands of homes, using mirrors to concentrate sunlight across acres of solar cells. Floating solar farms—or “floatovoltaics”—can be an effective use of wastewater facilities and bodies of water that aren’t ecologically sensitive.

Solar supplies a little more than 1 percent of U.S. electricity generation. But nearly a third of all new generating capacity came from solar in 2017, second only to natural gas.

Solar energy systems don’t produce air pollutants or greenhouse gases, and as long as they are responsibly sited, most solar panels have few environmental impacts beyond the manufacturing process.

Renewable Energy: Wind Energy

We’ve come a long way from old-fashioned wind mills. Today, turbines as tall as skyscrapers—with turbines nearly as wide in diameter—stand at attention around the world. Wind energy turns a turbine’s blades, which feeds an electric generator and produces electricity.

Wind, which accounts for a little more than 6 percent of U.S. generation, has become the cheapest energy source in many parts of the country. Top wind power states include California, Texas, Oklahoma, Kansas, and Iowa, though turbines can be placed anywhere with high wind speeds—such as hilltops and open plains—or even offshore in open water.

Renewable Energy: Hydroelectric Power

Hydropower is the largest renewable energy source for electricity in the United States, though wind energy is soon expected to take over the lead.

Hydropower relies on water—typically fast-moving water in a large river or rapidly descending water from a high point—and converts the force of that water into electricity by spinning a generator’s turbine blades.

Nationally and internationally, large hydroelectric plants—or mega-dams—are often considered to be nonrenewable energy. Mega-dams divert and reduce natural flows, restricting access for animal and human populations that rely on rivers. Small hydroelectric plants (an installed capacity below about 40 megawatts), carefully managed, do not tend to cause as much environmental damage, as they divert only a fraction of flow.

FAQ: renewable Energy

Renewable energy, often referred to as clean energy, comes from natural sources or processes that are constantly replenished. For example, sunlight or wind keep shining and blowing, even if their availability depends on time and weather.

  • Burlington, USA: Vermont’s largest city now obtains 100% of its electricity from wind, solar, hydro, and biomass. …
  • Reykjavik, Iceland: sources all electricity from hydropower and geothermal, and is now working to make all cars and public transit fossil-free by 204

 

Is Renewable Energy Reliable? Studies by the experts who plan and operate the electricity grid show that much higher levels of renewable energy can be achieved reliably, while significantly reducing carbon emissions.

 

Renewable energy sources make up 26% of the world’s electricity today, but according to the IEA its share is expected to reach 30% by 2024. … Overall, renewable electricity is predicted to grow by 1 200 GW by 2024, the equivalent of the total electricity capacity of the US