The watt (symbol: W) is the power unit of the International System, it is the amount of energy in joules that is converted, used or dissipated in one second. It is a derived unit that takes its name from the engineer, inventor and constructor of Scottish instruments James Watt, for his contribution to the development of the steam engine, which was one of the triggers of the beginning of the Industrial Revolution.
The watt unit was adopted by the Second Congress of the British Association for the Advancement of Science in 1889, which meant its international recognition as a power unit,…
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…
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…
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…
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.
Geothermal power plants are the plants responsible for converting geothermal energy into electricity. A geothermal plant is a facility where electricity is generated by geothermal energy.
Geothermal energy is the thermal energy contained inside the Earth. These facilities perform a thermodynamic exchange at a certain depth of the terrestrial layers to heat a fluid. This heat is used to generate electricity. Because the heat inside the Earth is inexhaustible, it can be said that this form of electricity generation is a source of renewable energy.
One kilowatt (kw) is a power unit in current use, equivalent to 1000 watts (w).
One watt (w) is a power unit of the international system equivalent to one joule per second.
If we express the watt in units used in electricity, we can say that a watt is the electric power produced by a potential difference of 1 volt and an electric current of 1 ampere (1 volt ampere).
Frequently the watt hour (Wh) is also spoken as an energy unit. The watt hour is a practical unit of energy equivalent to the energy produced by a power of one watt for one hour. Common errors related…
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…
A photovoltaic solar installation connected to the network has only three basic elements:
- A group of photovoltaic solar panels. These solar panels are usually located on the roof of a building or integrated into any structural element of the same building. The photovoltaic panels can also be arranged directly on any land near the electricity grid.
- Ondulator or electronic inverter-converter. This device transforms the energy in the form of direct current provided by the solar panels, in alternating current of the same type and value as the one transported by the electric…
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…
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…
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…
Geothermal energy is that energy that can be obtained by man through the use of heat from the interior of the Earth. This type of energy has many applications. One of these applications is the generation of electric power.
The generation of electricity from geothermal energy is a good complement for hydroelectric plants, which also has the advantage that it is constant throughout the year. Geothermal plant
Geothermal power plants are the plants responsible for converting geothermal energy into electricity. A geothermal plant is a facility where electricity is generated…
In the beginnings 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, at 12, 24, 48 volts in direct current. This made a big difference with the users who had electricity distribution network or generator sets at 220 volts alternating current.
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…
A mini-hydraulic power plant is a power plant that uses hydropower for the production of electricity. They are characterized by the fact of having a reduced installed power. Its small size implies the use of structures of much smaller size than a normal dam. These mini-hydraulic plants are safer, thanks to the smaller volume of water in the basin, and which also have a lower environmental impact and landscape.
There is no globally accepted limit for which a hydroelectric plant is defined as mini-hydraulic. According to the ESHA (European Association of Small Hydroelectric Power Plants),…
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 installation of large photovoltaic power plants in the world continues to increase both in number and installed power. As of today, there is already an installation in India that produces 1000MW. However, even larger photovoltaic solar power plants are still being built.
In this sense, the countries that lead the production of photovoltaic solar energy are China, the United States and India.
From the main photovoltaic solar installations in the world we highlight: Kurnool Ultra Mega Solar Park. 1,000 MW. India
The Krnool Ultra Mega Solar photovoltaic park is located…
In the field of renewable energies, there are other renewable technologies in the development phase. Cellulosic ethanol, geothermal energy from hot and dry rock and marine energy are technologies that can complement traditional photovoltaic solar energy, wind energy or hydropower, for example.
However, these technologies are not yet sufficiently developed or have limited commercialization. Many of these new sources of renewable energy have great potential, but they still have a long way to go in research and development.
There are numerous organizations within the academic…
Hydropower is a source of renewable energy that uses water to generate energy. Normally, it uses the potential energy of water at a certain height to generate turbines and with them, electricity.
The mechanism of operation is to take advantage of the potential energy of water at a certain height, it is dropped to convert this energy into kinetic energy. With the kinetic energy of water a turbine that is connected to an electric generator is activated.
Generally, the installations responsible for hydroelectric production are hydroelectric power plants. Usually these facilities…
Nuclear energy is the energy that is obtained from the division (nuclear fission) or from the union (nuclear fusion) of an atom. Despite the existence of a large number of applications related to nuclear energy (medicine, industry, transport, etc.), the main application of this technology is the generation of electrical energy.
Electricity of nuclear origin is generated in nuclear power plants. At present, all nuclear power plants operate through nuclear fission reactions. The nuclear fuel they use is usually uranium or plutonium (by an artificial process). Because…
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…
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,…
Hybrid solar energy systems are hybrid energy systems that combine the solar energy of a photovoltaic system with another source of energy that generates energy. A common type is a hybrid photovoltaic diesel system, which combines solar photovoltaic (PV) and diesel generators, or diesel generator sets, since PV has only a marginal cost and is treated with priority in the network. Diesel generator sets are used to constantly fill the gap between the current load and the actual power generated by the photovoltaic system.
Since the solar energy fluctuates and the generation capacity of…
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.…
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…
A hydroelectric power plant is a set of hydraulic engineering working located in a certain succession, together with a series of suitable machines. The objective of a hydroelectric power plant is to obtain electricity from the potential energy of moving bodies of water. This is what is called hydropower.
The energy produced by hydroelectric plants must be classified in all aspects as renewable energy because, at least in theory, water can be reused endlessly for the same purpose without undergoing a purification process. The concept of renewability is subordinated to the constancy of…
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…
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…
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…
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.…
Wind energy is a source of energy that is becoming very popular in many countries of the world. The advantages associated with the use of wind energy (renewable energy, clean, respectful with the environment, etc.) are helping a lot to its growth and implementation in many countries.
However, the disadvantages of wind power are also notable and must be considered before investing in a wind power plant. Sometimes the contrast between advantages and disadvantages of solar energy or other sources of energy can vary from one place to another.
In this article we analyze the…
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…
Geothermal energy is a long-term source of energy worldwide. With the geothermal energy stored in the top three kilometers of the Earth's crust, theoretically, the current energy demand could be covered for more than 100,000 years. However, only a small part of this energy is technically usable and the effects on the earth's crust during extensive heat dissipation are not yet clear.
When geothermal energy is used, a distinction is made between direct use, that is, the use of heat in itself, and indirect use, the use for conversion into electricity in a geothermal power plant. With the…
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…
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…
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 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,…
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.
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.…
The balance of system (also known by the acronym BOS) includes all the components of a photovoltaic system with the exception of photovoltaic panels. The balance of system is constituted, typically, by the electrochemical accumulator in the case of some isolated systems of the network, the control unit and the inverter (electronic equipment), the mechanical support structure, the electrical wiring and the protection devices (fuses, ground connections and switches).
Other optional components in a solar BOS include, maximum power point monitoring (MPPT), GPS solar tracker, energy…
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…
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…
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.…
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…
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…
According to the first law of thermodynamics, every process that occurs in a given system must satisfy the principle of conservation of energy, including the flow of heat.
states, in other words, that any process whose sole purpose is to create or destroy energy, is impossible, that is, it denies the existence of a first-class perpetual motion machine.
However, the first law does not tell us anything about the…
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 generation of fuel through solar energy is a technique based on generating chemical reactions using solar radiation. These chemical processes allow the generation of energy that would otherwise come from a source of fossil fuel or nuclear energy.
A great advantage of the generation of solar fuels is that they can be transported and stored easily. However, adding a step in the generation of electric power (fuel generation) implies a reduction in efficiency: adding an additional step between the storage of energy and the production of electricity drastically decreases the…
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…
Geothermal energy is a type of renewable energy. It is considered renewable energy because it does not consume resources and is practically inexhaustible.
Its principle of operation is based on the use of heat inside the Earth. One of the most used techniques to take advantage of the internal energy of the rocks is to build wells of about 150 meters through which a fluid circulates. The fluid falls with a low temperature, at the bottom through a thermodynamic process it is heated and goes up with the thermal energy acquired to the surface.
It is a new technology…