The geothermal heat pump is an air conditioning system for buildings that exploits the heat exchange with the superficial subsoil, by means of a heat pump. Since the heat in the subsoil comes largely from the interior of the Earth, geothermal energy of low enthalpy is classified as a source of renewable energy, although the heat pump itself consumes electricity, generally produced from other sources of energy (for example, fossil fuels).
The heat pump allows the exchange of heat between a "source" at a lower temperature than the "well", or the point where the heat is introduced. In a…
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…
For the conversion of fossil energy into electrical energy, the technology of a thermal power plant is often used. At the moment in which a thermal power station is fossil fuels fossilized from a source of non-renewable energy generation.
A thermal power plant (or thermoelectric plant) is a plant that generates electricity by transforming heat. Historically heat energy is converted into electricity by transferring heat to a working fluid and then transforming the energy of this fluid into mechanical energy. Finally, mechanical energy is transformed into electricity. The…
Alternating current (AC) is a type of electrical current that is characterized by changing over time, either in intensity or direction, at regular intervals.
The voltage varies between the maximum and minimum values cyclically, the value of the voltage is positive half the time (positive half cycle or half positive period) and negative the other half. This means that half the time the current flows in one direction, the other half in the other direction. The most common form of undulation follows a sine-type trigonometric function, since it is the most efficient and practical…
An inverter is an electronic device. The function of the inverter is to change a DC input voltage to a symmetrical AC output voltage, with the magnitude and frequency desired by the user. The inverters use in a great variety of applications, from small power supplies for computers, to industrial applications to control high power. The inverters are also used to convert the direct current generated by photovoltaic solar panels, accumulators or batteries, etc., into alternating current and thus be able to be injected into the electrical network or used in isolated electrical installations.…
An inverter is an electronic device. The function of the inverter is to change a DC input voltage to a symmetrical AC output voltage, with the magnitude and frequency desired by the user. The inverters use in a great variety of applications, from small power supplies for computers, to industrial applications to control high power. The inverters are also used to convert the direct current generated by photovoltaic solar panels, accumulators or batteries, etc., into alternating current and thus be able to be injected into the electrical network or used in isolated electrical installations.
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…
A forced circulation for solar water heater is an installation in which the water circulates inside the circuit driven by a pump. With forced circulation system, the movement of water in the closed circuit is forced by a pump. This feature makes a big difference with respect to sanitary hot water installations with thermosyphon. In this way, it artificially moves the hot water not to the highest point of the closed circuit, but it does so from the solar collectors down to where the accumulator is located.
In many occasions it is not viable to install solar thermal equipment…
The Pelton turbine is a type of turbine used in the hydropower industry within the field of renewable energy.
A Pelton turbine is a hydraulic turbine of the impulse type used in hydroelectric power plants with high vertical height. It was Invent to by Lester Allan Pelton in the 1870s and Amend significantly by other inventors beyond late 1800. The Pelton turbine is a further development of traditional water wheel. The Pelton turbine transforms the hydropower into the impulse of one or more jets of water at…
Although in principle it seems that in an installation of photovoltaic solar energy just need solar modules and batteries, there is a key element in these facilities is what ensures that, in the charging process as in the discharge accumulators, is made so that they are always within the correct operating conditions: the charge controller.
Solar panels are designed so that they can give a higher than the end voltage battery charging voltage. This ensures that the solar panels are always able to charge the battery, even when the temperature of…
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…
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…
The Francis turbine is a hydraulic turbine used in hydropower installations with a considerable height of fall.
The Francis turbine is a type of hydraulic turbine built by British-American engineer James Bicheno Francis. The function of the Francis turbine is mainly to generate electricity with the help of a generator. Francis turbines have a high utilization capacity of more than 90% and a wide range of activities compared to the height (building drop) of the fluid flowing through the turbine. This is particularly emphasized in water where it achieves optimum performance in a building…
Hydraulic fracturing or geotechnical fracking is the exploitation of the pressure of a fluid, typically water, to create and then propagate a fracture in a layer of rock in the subsoil. Fracking is carried out after a drilling in a rock formation containing hydrocarbons (oil or natural gas). The objective is to increase the permeability. Improving permeability improves the production of oil or gas contained in the subsoil and increases its recovery rate.
Hydraulic fractures in rocks can be both natural and created by humans; they are created and enlarged by the pressure of the fluid…
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…
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…
The applications of photovoltaic solar energy are many and varied. In this field, they include from large power generation plants through photovoltaic panels, to small solar calculators.
A first way to classify the applications of photovoltaic solar energy is to distinguish the applications connected to the electrical network and the isolated installations.
The use of photovoltaic panels in isolated buildings is very useful since the investment needed to place solar panels on the roof of a farm, a chalet in the mountain or in a hotel in a secluded spot, is much less than what it…
What is wind power?
Wind energy is a renewable energy whose origin is wind. This energy source takes advantage of the kinetic energy generated by the effect of air currents to transform it into other useful forms for human activities. Historically, wind energy has been used since ancient times to move sail-driven boats or operate mill machinery when moving its blades.
The most common use of wind energy is the generation of electricity. Wind turbines are machines that convert the kinetic energy of wind into electrical energy.
Wind energy is an abundant, renewable,…
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…
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 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…
Definition of temperature: The temperature is the thermodynamic magnitude that shows the thermal energy of one body in relation to another.
Although the definition of temperature is simple and concise, you can explain what the temperature is in a more extensive way: What is the temperature?
Temperature is a physical quantity of matter that quantifies the common notions of heat and cold. The objects of low temperature perceive them cold, while objects of higher temperatures we consider them warm or hot. This physiological sensation of cold and heat is generated…
The batteries in a photovoltaic solar energy system is to accumulate the energy produced by the photovoltaic panels during the hours of Sun to be able to use it at night or on cloudy days.
The use of batteries also allows to provide a higher current intensity than a functioning photovoltaic panel can offer. This would be the case if several electrical appliances were used at the same time.
A battery consists of small 2V accumulators integrated in the same element; Has direct current at 6, 12, 24 or 48V. The accumulator is the cell that stores energy through an electrochemical…
Geothermal energy is a type of renewable energy on a human scale that is obtained from the heat of the interior of the Earth. Equestrian thermal energy can be obtained without the combustion of any material, it is therefore a form of clean energy without carbon dioxide emissions.
The temperature in the inner layers of the Earth remains constant during the different seasons of the year. Generally the inner layers are hotter than the surface in winter and cooler in summer. This is because the surface layers are heated and cooled more easily according to the laws of thermodynamics.…
Coal is a fossil fuel that is used to obtain fossil energy through its combustion. The thermodynamic properties of coal allow obtaining a large amount of heat energy during its combustion process.
Coal is a natural resource limited. The generation of coal is a process of several million years, while the consumption of this energy resource is very fast. For this reason, coal is considered a non-renewable source of energy.
Coal is a sedimentary rock of organic origin, black or dark brown. It is used mainly as a fossil fuel because of its high calorific value…
A photovoltaic panel is a type of solar panel designed for the use of photovoltaic solar energy. Its function is to transform solar energy into electricity.
Photovoltaic panels can be used to generate electrical power in both domestic applications and commercial applications.
The photovoltaic modules are formed by a set of interconnected photovoltaic cells. The photovoltaic cells that make up a photovoltaic panel are embedded and protected. The photovoltaic panel is in charge of directly transforming the energy of solar radiation into electricity, in the form of direct current.…
In thermodynamics, a thermodynamic cycle is a circuit of thermodynamic transformations performed on one or more intended devices. The objective of these transformations is to obtain work from two sources of heat at different temperatures, or conversely, to produce through the contribution of work the passage of heat from the source of lower temperature to higher temperature.
Obtaining work from two thermal sources at different temperatures is used to produce movement, for example, in thermal engines or alternators used in the generation of electrical energy. Performance is…
Hydropower is the electric power produced in a hydroelectric power station from a current, vertical or horizontal, of a river. In other words, it is electricity (electrical energy) obtained from hydraulic energy (mechanical energy of water in movement of rivers, lakes and marshes).
The difference between hydroelectric and hydraulic energy is that hydraulic energy can be used to generate electrical energy but also to obtain energy of another type, for example, mechanical energy. While hydropower refers only to the use of hydropower to obtain electric power or electricity.
Fossil fuels are non-renewable energy resources because they require millions of years for their formation in a natural way. Due to their high calorific power they are useful energy sources to generate thermal energy and their use has allowed the great economic and demographic growth linked to the industrial revolution of the 19th century. Although now they are fundamental for our economy. In 2007, the combustion of coal, oil and natural gas accounted for 86.4% of the world's primary energy. However, its combustion is one of the main sources of atmospheric pollution and global warming, which…
What is silicon?
Silicon is a chemical element of atomic number 14 and symbol Si. This chemical element belongs to group IV A of the periodic table. JJ Berzelius 1824 isolated it by reduction with potassium of silicon tetrafluoride (SiF4).
The crystalline elemental silicon is grayish in color with a metallic luster, very hard, with very high melting and boiling points, and is an intrinsic semiconductor. The amorphous form of the element occurs in brown powders, conductive of electricity, which can be easily melted and vaporized.…
At the end of the 17th century, the Earth was conceived as a molten mass with a solid crust as a result of its cooling. It was not until the 19th century that the first calculations of the age of the Earth based on its thermal evolution were drawn up, and the term geothermal was first defined as the scientific discipline that studies earth's heat, origin of this heat, distribution and use.
Precisely, the use of this thermal energy is what has led to the development of geothermal energy. Geothermal energy allows us to take advantage of the heat energy inside the Earth in different applications,…
Fossil fuels are often spoken of as a type of negative, polluting energy, harmful to the environment. Fossil fuels are considered a non-renewable energy source due to the difficulty of regeneration.
Currently, fossil fuels are the most widely used energy source in the world. It is used to generate electrical energy but above all it is also used to generate mechanical energy (cars, heat engines, etc.)
The theory that fossil fuels formed from the fossilized remains of dead plants by exposure to heat and pressure in the earth's crust for millions of years was first introduced…
Tidal energy is the energy obtained from the movements of water caused by the tides. It represents a source of renewable energy since it uses an inexhaustible resource.
The tide, the rhythmic rise and fall of sea level caused by the gravitational action of the moon and the sun, generally has a width (difference between high tide and low tide) of less than one meter, but in some areas, due to the particular configuration of the site, the difference in height can reach high values, interesting for the exploitation and production of energy, which is currently predominantly electrical. In…
Monocrystalline silicon is the base material for the silicon chips used in practically all current electronic equipment. In the field of solar energy, monocrystalline silicon is also used to manufacture photovoltaic cells due to its ability to absorb radiation.
Monocrystalline silicon consists of silicon in which the crystalline lattice of the entire solid is continuous, does not break at its edges and is free of any grain limit. Monocrystalline silicon can be prepared as an intrinsic semiconductor that is composed only of very pure silicon, or can be doped by the addition of other elements…
A turbine is a turbomachine that converts the flow energy of a fluid (liquid or gas) into mechanical energy by means of a system of rotating blades. This mechanical energy can be used to power another machine or an electric generator.
The turbine name was proposed by Claude Burdin during an engineering contest in 1828. This name comes from the Latin turbine, which means Foucault current.
A simple turbine consists of a single rotor with blades, which provide energy exchange with the flow. The first examples of turbines are wind turbines and water mills, that is, for wind…
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 steam turbine is a device that is used to convert the high pressure of the steam into the rotation of an axis that provides power output (shaft). This type of turbine is mainly used in power plants (for example, in high temperature solar thermal power plants), but also in other applications where large capacities are required, such as offshore vessels.
With a modern steam turbine, the steam is guided against a row of rotor blades, which changes the steam direction as much as possible. Then, the steam passes through a row of stator blades, where it again rotates from the direction…
The notion of watt-peak is used to compare the performance of photovoltaic solar installations and to predict the amount of electricity that can be produced under optimal conditions.
To compare the capacity of solar panels, there are established standard conditions: at an irradiance of 1 kW / m², whose spectrum corresponds to the spectrum of sunlight in an air mass of 1.5 (this means that sunlight passing through the atmosphere is equal one and a half times the average thickness of the atmosphere), and a cell temperature of 25 ° C.
The objective of having the maximum…
Hydropower is a source of renewable energy or alternative energy. This renewable energy exploits the transformation of gravitational potential energy, possessed by a certain mass of water at a certain elevation, in kinetic energy to overcome a certain difference in height. The mechanical energy obtained can be used directly to rotate the shaft of a turbine or in some application or machine that works using hydropower. The most common is to use this kinetic energy to generate electrical energy. In this case, we talk about hydroelectric power.
In hydroelectric power, the kinetic energy…
Geothermal energy is a renewable energy obtained from the heat stored inside the Earth. Thanks to the laws of thermodynamics, thermal energy is transferred from the interior of the Earth to a fluid. In this way, energy is transported in the form of internal energy.
Geothermal energy is basicaly based simply on taking advantage of the fact that the subsoil temperature is warmer than on the surface, in winter, and instead cooler, in summer. This is a consequence of the fact that the surface layers of the Earth are heated and cooled much more easily than the interior, which is maintained…
In the market there are several types of photovoltaic solar panels for domestic use. The most common types are monocrystalline photovoltaic panels, polycrystalline solar panels and thin-film solar panels.
Around 90% of the photovoltaic technology is based on the use of some silicon variation. In the case of solar panels intended for domestic use, this percentage is even higher.
The main difference between the different types of photovoltaic panels is the purity of the silicon used. The purer the silicon, the better aligned its molecules are, and the better it converts solar energy…
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.…
Natural gas is a source of fossil energy, like coal or oil, it is constituted by a mixture of hydrocarbons, molecules formed by carbon and hydrogen atoms. Its calorific value varies greatly according to its composition, but the highest are between 8,500 and 10,200 kilocalories per cubic meter of natural gas.
Natural gas is a primary energy, or that can be obtained directly without transformation. The other primary energies are solar energy, coal and oil. It is the cleanest fossil energy in terms of waste and atmospheric emissions, and the most efficient fuel for obtaining electricity…
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,…
In the early days of photovoltaic solar energy, the electrification facilities used electricity for consumption at the same voltage and with the same form that they received from photovoltaic solar panels and accumulators, that is, 12, 24, 48 volts in direct current. This made a big difference with the users that had electricity distribution network or generator sets at 220 volts AC.
The appliance market has adapted to the majority of users and we can find any appliance with 220 volts of alternating current. Therefore, getting reliable, quality, and reasonably priced appliances that…
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.
Renewable energy is that energy that comes from practically 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.
In most cases they are simple to dismantle and it is not necessary to guard their waste, as it…
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…
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.…