What is Renewable Energy? Explained

Renewable energy, is often referred to as clean energy, comes from natural sources or processes that are constantly replenished

To understand the renewable energy better, here are the most common examples are wind, solar, geothermal, biomass, and hydropower

It is important to note that the terms ‘renewable energy’, ‘green energy’ and ‘clean energy’ are not interchangeable in all cases; for example, a ‘clean’ coal plant is simply a coal plant with emissions reduction technology. The coal plant itself is still not a ‘renewable energy’ source.

Renewable energy systems provide energy from sources that will never deplete. Renewable energy systems produce less greenhouse gas emissions than fossil fuel energy systems.

Types of Renewable Energy


1. 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.

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.

2. Wind Energy:

Wind energy turns a turbine’s blades, which feeds an electric generator and produces electricity. Wind turbines as tall as skyscrapers—with turbines nearly as wide in diameter—stand at attention around the world.

3. Hydroelectric Power:

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.

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.

4. Biomass Energy:

Biomass is organic material that comes from plants and animals, and includes crops, waste wood, and trees. When biomass is burned, the chemical energy is released as heat and can generate electricity with a steam turbine. some forms of biomass energy could serve as a low-carbon option under the right circumstances.

For example, sawdust and chips from sawmills that would otherwise quickly decompose and release carbon can be a low-carbon energy source.

5. Geothermal Energy:

Geothermal plants typically have low emissions if they pump the steam and water they use back into the reservoir. There are ways to create geothermal plants where there are not underground reservoirs, but there are concerns that they may increase the risk of an earthquake in areas already considered geological hot spots.

‘Green energy’ is a subset of renewable energy, which boasts low or zero emissions and low environmental impacts to systems such as land and water.

6. Ocean Energy:

Tidal and wave energy is still in a developmental phase, but the ocean will always be ruled by the moon’s gravity, which makes harnessing its power an attractive option.

Some tidal energy approaches may harm wildlife, such as tidal barrages, which work much like dams and are located in an ocean bay or lagoon. Like tidal power, wave power relies on dam-like structures or ocean floor–anchored devices on or just below the water’s surface.

While renewable energy systems are better for the environment and produce less emissions than conventional energy sources, many of these sources still face difficulties in being deployed at a large scale including, but not limited to, technological barriers, high start-up capital costs, and intermittency challenges.