You hear more and more frequently about clean energy or green energy. It is a type of energy that is characterized by its respect for the environment and its low impact on the environment, totally contrary to dirty or polluting energies. However, could you tell what they are and what differentiates them from the rest of the energies?
What are clean or green energies – the answer
The clean or green energy , as its name suggests, are those that do not produce polluting waste or harmful to the planet and to health. These are energies that are obtained from different natural sources , such as the sun, wind or rain. In all cases of clean energies, we are also talking about renewable energies , since they are energies that, potentially, will never be exhausted.
These types of energies are the ones that are currently being promoted the most with the aim of slowing down, and even counteracting the effects of climate change . This process is what is known as the energy transition, which consists of the transition from an energy sector based on carbon (energies obtained from the burning of fossil fuels such as coal and oil) to one based on renewable energies, where clean energies play a leading role.
What are clean energies or green energies
Although clean energy can take many forms and it is a sector that is constantly changing and progressing, the most widespread clean or green energies today are the following:
It is the energy that is obtained thanks to the light and heat of the sun. It can be in two ways depending on whether light or heat is used. In the case of taking advantage of sunlight, this is done through solar panels, which, broadly speaking, are devices capable of transforming photons from light into usable electrical current for human activities. This type of energy is called photovoltaic.
In the case of taking advantage of the sun’s heat, we will be talking about solar thermal energy. This type of solar energy is used by large installations with many mirrors that direct and concentrate the sun’s rays at the same point, which is able to heat this point very much and, in this way, activate a mechanical system that is capable of producing movement. which will later be transformed into useful electrical energy for humans.
It is about the energy obtained from the use of the flow of rivers and the natural movement of water. In the case of hydropower , the energy is obtained by installing turbines on the banks or dams of rivers, which allows the turbines to move like watermills. Later, this movement is converted into electrical energy that, again, can be used for human activities.
The wind energy is the energy obtained from the wind. The system is similar to that of hydraulic power but, on this occasion, windmills (also called wind turbines) are installed in points where the wind is abundant, such as esplanades on land or in coastal areas over the sea. The wind turns the blades of the windmill and, in this way, the movement can be converted back into electricity that is sent to the electrical network.
It is about the energy that is obtained thanks to the use of the tides. This is achieved by installing an alternator that, taking advantage of the rise and fall of the tides, transforms the movement of the sea into electricity.
In the case of geothermal energy , we are dealing with an energy that is obtained from the use of heat from the interior of the Earth. By means of an installation that captures heat, it is possible to activate a mechanical system that, in turn, is in charge of producing electrical energy that can be used for human activity.
The nuclear energy is a very special energy because it is not an energy associated with carbon and therefore might seem at first that would be a clean energy. However, nuclear energy is not exempt from producing highly polluting waste. In this case, radioactive waste that has to be properly isolated to avoid very serious damage to the environment and the health of living beings. Therefore, although it is an energy that is not linked to the burning of fossil fuels, it cannot be considered as clean energy.
On the other hand we find biofuels . This type of energy is obtained from the burning of fuels that are obtained from the reuse of organic matter. This can be done by burning wood such as pellets, or by burning biogas, a type of gas that is obtained from the rotting of organic matter in certain circumstances. This type of energy promises to play a relevant role in the future, since they are much more environmentally friendly fuels. In fact, because it is an energy that can be obtained from organic matter, at least in principle, it could be considered as a renewable energy in its own right. However, it is important to bear in mind that, with its burning, greenhouse gases (GHG) are released, although in much smaller quantities than when coal or petroleum derivatives are burned.