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What Is Clean Energy? Characteristics, Definition and Examples

What is clean energy? characteristics, definition and examples

A clean energy is an energy source in which there is no emission of greenhouse gases such as carbon dioxide or other pollutants. They are types of energy that respect the environment and do not contribute to the Earth's climate change.

Traditionally, the main way of generating electricity has been by burning fossil fuels (mainly coal and natural gas). Fossil energy is one of the main sources of polluting gas emissions.

When solar radiation reaches the earth, some of this radiation bounces off the surface. Some of this bounced radiation is trapped by particles in the atmosphere and the rest goes back into space.

This energy capture is necessary to keep the planet at a temperature suitable for life. However, the excess gases in the atmosphere causes the captured heat to be excessive, leading to global warming of the planet.

Is Clean Energy the Same as Renewable Energy?

Clean energy and renewable energy are different concepts.

A renewable energy source is an energy source that uses an inexhaustible resource, but does not imply that it is clean.

For instance,

  • Biomass is a renewable energy source but it generates greenhouse gases.

  • Nuclear energy does not emit polluting gases but it is neither renewable (uranium is limited) nor is it clean (it generates radioactive waste).

  • Solar energy and wind energy are clean and renewable energies, since they do not pollute and use inexhaustible resources.

  • Fossil energy is neither clean nor renewable as it emits greenhouse gases and the fuel used takes millions of years to regenerate.

Characteristics of Clean Energies

Clean energies meet the following characteristics:

  • All clean energies are renewable (but not the other way around).

  • They do not generate polluting waste such as radioactive waste.

  • They do not emit greenhouse gases, therefore they do not contribute to global warming or climate change.

  • They reduce dependence on other polluting energy resources.

  • Its exploitation is environmentally sustainable.

Examples of Clean Energy Sources

Below we list 6 examples of clean energy sources.

1. Solar Energy

Solar energy is that form of clean and renewable energy produced by the exploitation of sunlight or by the rays that the sun radiates towards the Earth.

The solar energy that reaches the earth's surface is 10,000 times higher than all the energy used by man and is used effectively for the production of heat and electricity thanks to photovoltaic panels.

2. Hydraulic Power

Hydroelectric energy takes advantage of mechanical force and water is obtained from rivers and lakes thanks to dams and gates.

The potential energy of the masses of water at high altitude is transformed into kinetic energy, from which electricity is then produced thanks to a turbine alternator.

3. Tidal Energy 

Tidal energy is capable of transforming tidal energy and transforming it into electrical energy. The gravitational influence of the Moon generates differences in the height of the sea level.

When the tide is high, water accumulates through coastal reservoirs and when it is low it is released to power hydraulic turbines.

4. Wave Energy

Wave energy takes advantage of the movement of waves and water displacements caused by tides and ocean currents. It is also called wave energy.

5. Wind Energy

Wind energy takes advantage of the kinetic force of the wind to produce electrical or mechanical energy. Wind turbines are windmills that transform the force of the wind into electricity.

6. Geothermal Energy

Geothermal energy uses heat from the Earth's interior and from volcanic areas to produce clean, renewable energy.

As it descends deeper into the earth's crust, temperatures tend to rise, averaging 3 ° C per 100 meters.

By taking advantage of the heat of these areas, through the principle of geothermal energy, it is possible to recover energy by transporting the vapors from the subsoil to the turbines used for the production of electricity and taking advantage of the water vapor for heating or other uses.


Published: October 13, 2021
Last review: October 13, 2021