Solar radiation is the radiant energy emitted in the interplanetary space of the Sun. This radiation is generated from thermonuclear fusion reactions that occur in the solar nucleus and produce electromagnetic radiation at several frequencies or wavelengths, which it then propagates in space at the typical speeds of these waves. This spread allows you to bring solar energy with them.
The solar constant is the amount of energy received in the form of solar radiation per unit of time and unit of surface, measured in the outer part of the Earth's atmosphere in a plane perpendicular to the…
Solar irradiation is the magnitude that measures the energy per unit area of incident solar radiation on a surface placed in a well-specified place and time range.
The solar irradiation in the terrestrial surface is, from the technical point of view, the addition in a determined interval of the solar radiance filtered by the interposition of the atmosphere.
The value of solar irradiation on the surface depends on the time of year, latitude, local climatology and times of day. Origin of solar irradiation
The origin of electromagnetic radiation from the Sun.…
The flat plate solar collector is a type of solar thermal panel whose objective is to transform solar radiation into thermal energy. This type of solar collector has a good cost / effectiveness ratio in moderate climates and adapts correctly to a large number of applications of solar thermal energy (heating of sanitary water, heating of swimming pools, support for heating, preheating industrial fluids , etc.).
We can distinguish two basic types of flat plate solar collectors, depending on the configuration of the absorber: the "grid type" parallel, in the vertical and horizontal…
The solar thermal energy consists of the use of the energy coming from the Sun to transfer it to a medium that carries heat, generally water or air.
Among the different applications of solar thermal energy there is the possibility of generating electrical energy. The current technology allows heating water with solar radiation to produce steam and then obtain electrical energy.
Although the principle of operation is very similar there are two main applications of solar thermal energy:
- Use of solar thermal energy in homes and small installations…
The greenhouse effect is the process by which the atmosphere of a planet passes solar radiation from the Sun, but instead prevents or hinders the thermal energy output of the planet.
It is called greenhouse effect due to the similarity with the operation of the greenhouses that are able to retain the heat inside. The operation is not exactly the same, but it is very similar. The difference is that the greenhouse uses the glass and not the gases in the atmosphere to retain heat. That is why this natural phenomenon has been called the greenhouse effect.
When we talk about the greenhouse…
Low-temperature solar thermal installations are considered those installations of solar thermal energy that provide useful heat at temperatures below 65 ° C through solar energy.
A low-temperature solar thermal installation consists of solar collectors, two water circuits (primary and secondary), heat exchanger, accumulator, expansion vessel and pipes.
The circulation of water inside the circuits can be obtained by thermosiphon, taking advantage of the density difference of the water at different temperatures or by means of a circulation pump. Although with a circulation…
Passive solar energy is based on the use of solar energy without the need to use external support mechanisms. By these mechanisms we refer to the use of electric motors to orient solar panels or similar systems.
The objective is to obtain personal thermal comfort. Personal thermal comfort is a function of personal health factors (medical, psychological, sociological and situational), ambient air temperature, average radiant temperature, air movement (thermal sensation, turbulence) and relative humidity (which affects human evaporative cooling).
To use passive solar energy…
The bioclimatic architecture enters what is called passive solar energy. This type of architecture uses natural elements of the place (sun, wind, water, soil and vegetation) to achieve thermally efficient buildings capable of satisfying thermal comfort requirements, regardless of the use of air conditioning systems.
The bioclimatic approach is related to the principle of self-sufficiency and the realization that the main phenomena that negatively affect the environment are caused by the consumption of large amounts of non-renewable energy, fossil fuels or nuclear energy. Construction…
Solar thermal energy is a way to harness the heat of solar energy from to get heat. Of the different techniques to convert solar radiation into thermal energy, in this section, we explain high-temperature solar thermal energy.
We refer to high-temperature solar thermal energy to those solar systems that use solar collectors that work at temperatures above 500ºC. In this type of installations, once the solar radiation has been transformed into heat energy, the next objective is to transform this heat into electrical energy.
The photovoltaic effect is the photoelectric effect characterized by the production of an electric current between two pieces of different material that are in contact and exposed to light or, in general, to electromagnetic radiation.
The photovoltaic effect consists of converting sunlight into electrical energy by means of photovoltaic cells. These cells are semiconductor devices made from pure silicon with the addition of impurities of certain chemical elements. Photovoltaic cells are capable of generating electricity in direct current, using solar radiation as a source.
The term solar energy refers to the use of the energy that comes from the Sun. It is a type of renewable energy. The energy contained in the Sun is so abundant that it is considered inexhaustible. The Sun takes 5 billion years emitting solar radiation and it is estimated that it has not yet reached 50% of its existence.
Solar energy, in addition to being inexhaustible is abundant: the amount of energy that the Sun pours daily on…
Within the history of solar energy, in one form or another, solar energy has always been present in the life of the planet being this imprescidible for the development of life. However, the way in which human civilization has exploited it invented new strategies and tools has undergone a long evolution.
The Sun is indispensable for the existence of life on the planet: it is responsible for the water cycle, photosynthesis, etc. Already the first civilizations realized this and, as civilizations have evolved, they have also evolved techniques to harness their energy. At the beginning they…
A solar concentrator is a concentration system of solar energy that is used to convert solar energy into thermal energy. Its operation is based on the exploitation of the reflection of the solar rays obtained through reflective surfaces (substantially of mirrors), in order to concentrate on a receiver of contained size. Similar to a magnifying glass focusing its light on a point, the concentrators reflect sunlight by means of an arrangement of mirrors aligned towards a lens capable of capturing that energy for its use.
In general, heat is converted into mechanical energy by means of…
A photovoltaic power plant or a photovoltaic power station is a set of facilities designed to supply electricity to the grid through the use of large-scale photovoltaic systems. The function of the photovoltaic power station is to capture and transform solar radiation into electricity.
A photovoltaic power plant is a power plant consisting of photovoltaic modules and an inverter. The photovoltaic panels are in charge of transforming the solar radiation, into electrical energy of direct current. The inverter is the electronic equipment whose function is to convert the direct…
Thermal energy is the energy released in the form of heat. It can also be called heat energy. In a more technical way we can define thermal energy as part of the internal energy of a thermodynamic system in equilibrium that is proportional to its absolute temperature and is increased or decreased by energy transfer.
The thermal energy can be transformed using a thermal engine (a thermoelectric power plant uses thermal energy to generate electricity); or in mechanical work (for example, a car, airplane or ship engine).
The obtaining of thermal energy can imply an environmental…
The efficiency of photovoltaic cells is one of the elements that determine the production of a photovoltaic solar energy installation. The other factors that determine the performance of a solar plant are latitude and climate.
The conversion efficiency value of a photovoltaic cell depends on several factors. When we refer to conversion efficiency, we refer implicitly to the thermodynamic efficiency, to the separation efficiency of the load carrier, to the reflectance efficiency and to the values of conduction efficiency. These parameters are difficult to measure…
The most important part of a photovoltaic module is the set of photovoltaic cells that are responsible for the transformation of solar radiation into electrical energy. The rest of the elements that are part of a solar panel have the function of protecting and giving firmness and functionality to the whole.
The photovoltaic cells are encapsulated with reinforced glass and several layers of plastic material. Subsequently, all this set is reinforced by forming an outer frame with aluminum metal profiles.
The photovoltaic solar panels that are used at present are formed of the following…
The photovoltaic cells are responsible for converting solar radiation into electrical energy in the form of direct current. Photoelectric cells are an indispensable element for this type of renewable energy.
There are different types of photoelectric cells depending on the nature and characteristics of the materials used. The most common type is the crystalline silicon cell (Si). This material is cut into very thin disc-shaped, monocrystalline or polycrystalline sheets, depending on the manufacturing process of the silicon bar.
The first crystalline cell that was manufactured…
One of the applications of solar thermal energy is the obtaining of sanitary hot water (DHW). Solar collectors capture the energy of solar radiation to increase the temperature of a fluid.
Domestic hot water (DHW) is water intended for human consumption (potable) that has been heated. It is used for sanitary uses (bathrooms, showers, etc.) and for other cleaning uses (washing dishes, washing machine, dishwasher, floor scrubbing). In terms of energy, the DHW is an important component to take into account, since it represents between 25 and 40% of the energy consumption of homes.
Autonomous photovoltaic installations are those installations that are isolated from the electricity grid. All the electrical energy generated by the solar panels is consumed directly.
This type of photovoltaic installations are designed for the cases in which the cost of maintenance and installation of power lines is not profitable. For example, this would be the case of mountain refuge.
The main element of autonomous photovoltaic installations is the photovoltaic panel. The photovoltaic panel is responsible for transforming solar radiation into electrical energy…
The function of a solar thermal installation is to take advantage of solar energy to generate heat. The solar panels of these facilities capture the heat of the solar radiation that falls on them to heat a fluid. The different ways to take advantage of this hot fluid allows us to use this type of renewable energy in multiple applications.
A solar thermal installation consists of:
- Solar collectors
- Primary and secondary circuits
- Heat exchanger
- Accumulator, pumps
- Glass of expansion
- Main control panel.
Low-temperature solar thermal energy is used in applications that require temperatures between 100ºC and 250ºC. From 80ºC the flat collectors practically no longer have any performance and it is necessary to resort to other capture systems.
Low-temperature thermal energy systems are used mainly for applications that demand thermal energy, that is, heat between 125º C and 400º C. To reach higher temperatures it is necessary to concentrate the solar radiation.
For this type of solar thermal energy, two types of solar collectors are used:
The parabolic cylinder solar collector is another type of solar thermal collector. This type of solar panel used in solar thermal installations uses parabolic cylinders to concentrate all the solar radiation in a point. Instead of heliostats, this type of collector employs parabolic trough mirrors. For the focus of the parabola passes a pipe that receives the concentrated rays of the Sun, where the fluid is heated, usually a thermal oil. Currently the fluid reaches temperatures close to 400º C.
Until recently, the use of thermal solar CCP concentration systems was restricted to…
The characteristics of solar energy imply certain advantages with respect to other sources of energy.
Although the characteristics are different in photovoltaic solar installations and solar thermal installations, we will treat the disadvantages globally.
Certain disadvantages of solar energy may imply that a solar installation may be unfeasible. The aspects to consider are the following:
- Energy efficiency is poor compared to other energy sources.
- The economic cost compared to other options.
- Performance is a function of the weather.
Photosynthesis is a chemical process that converts carbon dioxide into organic compounds, especially, using the energy of solar radiation.
Photosynthesis occurs in plants, algae, and some groups of bacteria, but not in archaea. Photosynthetic organisms are called "photoautotrophs," but not all organisms that use light as an energy source effect photosynthesis, since "photoheterotrophs" use organic compounds, not carbon dioxide, as a carbon source. In plants, algae and cyanobacteria, photosynthesis uses carbon dioxide and water, releasing oxygen as a waste product. photosynthesis is crucial…
Thermosolar energy is a technology to generate electricity or electricity by thermal energy from the Sun (solar heat). It is a type of solar thermal energy. Solar thermal energy is characterized by using solar radiation to heat a fluid. This hot fluid (usually water) can be used for many applications such as heating or hot water (DHW). But another application that can be given is the generation of electric power.
This type of energy is also often called thermoelectric power.
This process of electricity generation takes place in the so-called thermoelectric solar or solar thermal…
Photovoltaic modules or solar panels are devices that are used to capture the energy of the sun's light. Photovoltaic solar panels contain a set of solar cells that convert light into electricity. It is called solar because the sun is one of the strongest energy sources for this type of use. Solar cells are sometimes called photovoltaic cells, and photovoltaics literally means "light-electricity". Solar cells have the photovoltaic effect to absorb the sun's energy and cause electrical current to flow between two charged layers in the opposite direction.
Currently, the costs associated…
A photon is the quantum of energy in the form of electromagnetic radiation, emitted or absorbed by matter.
A photon is an elementary particle, the quantum of all forms of electromagnetic radiation, including light. It is the particle mediating the electromagnetic force, even when it is static through virtual photons.
The photon has zero mass at rest and consequently the interactions of this fundamental force are observable at both microscopic and macroscopic scale.
Like all elementary particles, photons are explained by quantum mechanics but exhibit wave-particle duality,…
A solar thermal power plant or thermosolar power plant is an industrial facility in which solar radiation is used to generate electricity. Solar radiation is used to heat a fluid. Using fluid, taking advantage of the laws of thermodynamics, the necessary power is produced to move an alternator to generate electrical energy as in a classic thermoelectric power station. Operation of a solar thermal power station
The operation of a solar thermal power plant is based on obtaining heat from solar radiation and transferring it to a heat carrier medium. This heat carrier is usually water.…
In this section we intend to answer the main questions related to solar energy.
Generally, these are general topics that could be located in several sections of the web. Our intention is to expand this section in the future to publish generalist articles and curiosities of nuclear energy.
Most of the questions are focused on small solar installations, comparative with solar thermal energy and photovoltaic solar energy.
In the future we will also answer on more oriented questions in the field of physics: thermodynamics, forms of energy, mechanical energy, potential energy,…
Any implementation of a sustainable photovoltaic solar energy system implies the optimization of the resources to be used. This is the basis of the design and assembly of solar installations.
To achieve optimum optimization of solar radiation, that is, the use of the Sun, it is essential to know the solar trajectory, the profile of the needs and the conditioners of the location. All this involves determining the orientation and inclination of the solar panels in fixed installations to achieve the minimum cost of the kilowatt hour of this type of renewable energy.
For reasons of…
A solar thermal collector is a component of a solar thermal installation. A solar collector is a type of solar panel responsible for capturing solar energy and transforming it into heat. It is also called the solar thermal collector.
The solar collector is the basic element of this renewable energy source.
From solar collectors there are many types. The solar collector used will depend on the use that is going to be given. For example, if we want to heat a pool to a temperature of 25-28ºC, in the spring, we need a simple sensor, since the ambient temperature will easily be…
In general, both photovoltaic solar energy and, above all, solar thermal energy has a very good acceptance in society. However, it is convenient to know the advantages and disadvantages of solar energy to reinforce or contrast our opinion.
When we talk about energy sources, most people are positioned in favor or against a certain type (solar energy, nuclear energy, wind power, etc.). The arguments for positioning are varied: energy efficiency, pollution, safety, cost ... Therefore, we will try to analyze the advantages and disadvantages of solar energy in the most objective way possible.…
Solar energy allows to take advantage of the energy that comes from solar radiation. One way to take advantage of sunlight is to convert the radiation into electrical energy (photovoltaic solar energy) or thermal energy (solar thermal energy). Photovoltaic solar energy requires a chemical process to obtain a continuous current, while solar thermal energy only requires a thermodynamic process.
The characteristics of solar energy imply certain advantages with respect to other sources of energy. Mainly if the other sources of energy are non-renewable energies that come from fossil fuels.…
Solar collectors are the elements that capture solar radiation and convert it into thermal energy, into heat. It is a type of solar panel designed for use in solar thermal installations. It is also known as a solar collector.
The function of solar thermal energy is to take advantage of solar energy to obtain heat, to heat a fluid. Unlike photovoltaic solar energy whose function is to generate electricity.
Solar collectors are those with flat plates, evacuated tubes and absorber collectors without protection or isolation. The flat (or flat plate) collection…
A solar furnace is an optical system to provide concentrated solar radiation. The concentrated energy of sunlight can be used for simple heating of a material, aging experiments of plastics or paints, endothermic chemical reactions or for charging experiments with mechanical or electrical components.
The solar furnace system is widely used in solar thermal power plants.
The principle of the solar furnace is also used to build cheap solar solar cookers, and for solar water pasteurisation. Solar furnace can be used to supply a Stirling engine, as well.
The difference between…
The Sun is a star around which the Earth turns.
It has an approximate diameter of 1,400,000 km and a mass of 1.99 × 1033 g.
The Sun revolves around itself. However, since it is constituted by a large mass of gases, the different regions do not rotate in solidarity, but they do so at different speeds, which depend on latitude.
The Sun, and with it the entire solar system, moves towards a point in the firmament located in the constellation of Hercules at a speed of about 19 km / s. This is because the Sun has a movement of translation around the galactic center, like…
A solar panel is a device to take advantage of solar energy. It can also be called a solar module.
Photovoltaic solar panels contain a set of solar cells that convert light into electricity. It is called solar because the sun is one of the strongest energy sources for this type of use. Solar cells are sometimes called photovoltaic cells, and photovoltaics literally means "light-electricity". Solar cells have the photovoltaic effect to absorb the sun's energy and cause electrical current to flow between two charged layers in the opposite direction.
The denomination of solar panel…
The electric current generated by a photovoltaic solar energy installation can be poured into the electricity grid as if it were a power plant. The consumption of electricity is independent of the energy generated by the photovoltaic panels. In these cases, the user continues to buy the electric energy consumed by the distribution company at the established price and also owns an electric power generation facility.
The most usual powers measured in vations are 2.5 and 5 kilowatts (kw) or multiples of 5 to 100 kilowatts (kw). There are larger solar installations, but they…
In the autonomous electricity supply facilities, it is necessary to store the energy captured during the hours of solar radiation in order to cover supply during the hours when there is no (daily cycle and seasonal cycle).
- Electric batteries have a very important and fundamental to the proper functioning and duration of a solar photovoltaic installation function.
- They must have sufficient capacity to ensure supply of electricity during periods of clouds (autonomy of installation).
- It is reversible electrochemical systems…
Renewable energy is energy that comes from virtually inexhaustible natural sources. They are considered inexhaustible either because of the large amount of energy they contain or because they can be regenerated naturally.
Among the main advantages of renewable energies we highlight the following:
Renewable energies are respectful with the environment and do not pollute. In this sense, they are safer and pose fewer health risks than other sources of non-renewable energy. The more energy generated by clean energies will need to generate fossil energy mes and decrease,…
Photovoltaic solar energy consists of the direct transformation of solar radiation into electrical energy. This type of energy is often referred to directly as photovoltaics.
This transformation in electrical energy is achieved by taking advantage of the properties of semiconductor materials through photovoltaic cells. The base material for the manufacture of photovoltaic panels is usually silicon. When sunlight (photons) hits one of the faces of the solar cell, it generates an electric current. This generated electricity can be used as an energy source.
In physics, in particular in thermodynamics, heat is defined as the contribution of transformed energy as a result of a chemical or nuclear reaction and transferred between two systems or between two parts of the same system. This energy is not attributable to a job or a conversion between two different types of energy. Heat is, therefore, a form of transferred energy and not a form of energy contained as internal energy.
As the energy is exchanged, the heat is measured in the International System in joules. In practice, however, it is often still used as the unit of measurement of calories,…
The constant price increases in electricity rates are reflected in the monthly bills of our home and therefore, more and more people are looking for alternatives to electricity and natural gas in order to save a few euros at the end of the month . One of these alternatives that has been implemented for a few years in Spain is self-consumption from solar panels .
With the installation of solar panels and the use of solar radiation, it is possible to generate electricity and / or heat in the home in a clean and renewable…