Among renewable energies, solar energy is one of the most important due to its continuous development and the possibility of using it practically all over the world. However, many people are still unsure about it. What is solar energy nor how it works at all.
In this article we clarify what solar energy is, its characteristics, types and most important advantages in its daily use and at an industrial level.
What is solar energy
Solar energy is that which takes advantage of electromagnetic radiation emitted by the sun to generate electricity or heat. It is a completely clean source of energy, which means that it does not pollute the environment or emit harmful gases into the atmosphere. In addition, it is a renewable and inexhaustible option (at least for several billion years, as long as the sun is active).
Once we understand what solar energy is, we will review the main types that exist: photovoltaic, thermal, passive and hybrid.
What is the photovoltaic energy
Photovoltaic solar energy is the type of energy that directly converts sunlight into electricity through solar panels. These panels are composed of Photo-voltaic cells, which are semiconductor devices (usually made of silicon) capable of absorbing photons of light and generating electrical energy. The most important thing about these cells is that They do not require moving parts or additional fuel to operate., which makes them very efficient and silent.
Each solar cell generates a small amount of energy, so it is necessary to group several cells together to form a photovoltaic module. These modules, when installed, generate a low voltage direct current (DC), so an inverter is needed to convert it into alternating current (AC), which can then be used in homes or industries.
The use of photovoltaic solar energy has grown exponentially in recent years, especially for residential and industrial installations, due to the ease of installing panels on roofs and rooftops.
What is solar thermal energy
Solar thermal energy, as its name suggests, is based on Harnessing solar radiation to generate heat. Instead of directly generating electricity as in photovoltaic systems, thermal energy uses solar collectors that concentrate the sun's rays to heat a fluid. This hot fluid can be used in various applications, such as heating water in homes and generating steam to produce electricity.
There are advanced variants such as Concentrated solar thermal energy, which uses mirrors to concentrate radiation at a specific point, allowing the fluid to be heated to much higher temperatures. This system is used primarily in large-scale power generation plants.
The use of solar thermal energy considerably reduces the consumption of fossil fuels, which contributes to the fight against climate change and the reduction of CO2 emissions.
What is passive solar energy?
Another modality is passive solar energy, which consists of taking advantage of the sun's rays without the need for additional devices such as solar panels or collectors. This technique is very common in bioclimatic architecture, where homes are designed to maximum use of sunlight through orientation and construction materials, which allow heat and light to be obtained without the use of electrical appliances.
Common examples of passive solar include designing south-facing windows to capture more light in winter or using thermally insulated roofs and walls to store heat from the sun.
What is hybrid solar energy?
Hybrid solar energy systems combine different forms of solar energy (photovoltaic, thermal or passive) with other renewable sources, such as wind energy. These systems seek to Maximize efficiency in energy production and are ideal for installations in rural areas or areas far from the electrical grid.
A hybrid system can include solar panels and wind turbines, allowing maximum use to be made of both resources, sun and wind.
Main uses of solar energy
Solar energy has multiple applications both at residential and industrial levels. Some of its most common uses are:
- Electricity generation: By means of photovoltaic solar panels, which transform solar radiation into electric current. It has become especially popular on the roofs of houses and large solar plants.
- Heating and hot water: Solar thermal systems allow heating water for heating and domestic use without the need for additional fuels.
- Public lighting: More and more cities are using solar panels to light streets, squares and parks without depending on the electricity grid.
- Agricultural irrigation: Solar pumps allow for automated irrigation in plantations, which optimizes water use and reduces energy costs.
Advantages of solar energy
- Clean and sustainable energy: It does not emit polluting gases and significantly reduces the carbon footprint.
- Renewable source: The sun is an inexhaustible source of energy.
- Energy independence: It allows people and communities to generate their own energy, reducing dependence on traditional electricity grids.
- Long-term cost reduction: Although the initial installation may be expensive, the savings on electricity bills are considerable over time.
It is clear that solar energy offers a viable and cost-effective solution to cover both residential and industrial energy needs while combating climate change.