Amoon renewable energy knowledge base

Renewable power is booming, as innovation brings down costs and starts to deliver on the promise of a clean energy future. Solar and wind generation are breaking records and being integrated into the national electricity grid without compromising reliability.

This means that renewables are increasingly displacing “dirty” fossil fuels in the power sector, offering the benefit of lower emissions of carbon and other types of pollution. But not all sources of energy marketed as “renewable” are beneficial to the environment. Biomass and large hydroelectric dams create difficult trade-offs when considering the impact on wildlife, climate change, and other issues. Here’s what you should know about the different types of renewable energy sources—and how you can use these emerging technologies in your own home.

What is renewable energy?

Renewable energy, often referred to as clean energy, comes from natural sources or processes that are constantly replenished. For example, sunlight and 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.

Now that we have innovative and less-expensive ways to capture and retain wind and solar energy, renewables are becoming a more important power source. The expansion in renewables is also happening at scales large and small, from giant offshore wind farms to rooftop solar panels on homes, which can sell power back to the grid. Even entire rural communities are relying on renewable energy for heating and lighting.

As renewable use continues to grow, a key goal will be to modernize electricity grid, making it smarter, more secure, and better integrated across regions.

Dirty energy

Nonrenewable, or “dirty,” energy includes fossil fuels such as oil, gas, and coal. Nonrenewable sources of energy are only available in limited amounts. When we pump gas at the station, we’re using a finite resource refined from crude oil that’s been around since prehistoric times.

Nonrenewable energy sources are also typically found in specific parts of the world, making them more plentiful in some nations than others. By contrast, every country has access to sunshine and wind. Prioritizing renewable energy can also improve national security by reducing a country’s reliance on exports from fossil fuel–rich nations.

Many nonrenewable energy sources can endanger the environment or human health. the technology associated with fracking can cause earthquakes and water pollution; and coal power plants foul the air. To top it off, all of these activities contribute to global warming.

Types of renewable energy sources

Solar energy

Humans have been harnessing solar energy for thousands of years—to grow crops, stay warm, and dry foods. According to the National Renewable Energy Laboratory, “more energy from the sun falls on the earth in one hour than is used by everyone in the world in one year.” Today, we use the sun’s rays in many ways—to heat homes and businesses, to warm water, and to power devices.