How is the use of solar energy developed on Earth?

The celestial body gives us a huge amount of energy for free. In just 15 minutes, the star gives our planet the amount of energy that is enough to provide humanity with electricity for one year. The quality and efficiency of solar panels are constantly improving and becoming cheaper. However, the mass use of solar energy is still far away. There are a number of problems, of which the efficiency of equipment for converting solar radiation is especially acute. This mainly concerns photovoltaic cells, the efficiency of which lies in the range of 12-17 percent. But back in the middle of the last century it was about 1%. So, progress is gradually happening, although not quickly. Therefore, in the future, solar energy should take its rightful place in the global energy sector. This material will discuss the use of solar energy in economic activity on Earth. Let's talk about problems and prospects, and also give examples of equipment.

The Sun serves as the primary source of all energy processes on Earth. The star sends 20 million exajoules towards our planet per year. Since the Earth is round, approximately 25% falls on it. Of this energy, approximately 70 percent is absorbed by the atmosphere, reflected and lost to other losses. 1.54 million exajoules fall onto the Earth's surface per year. This figure is several thousand times more than the energy consumption on the planet. In addition, this value is 5 times greater than the entire energy potential of hydrocarbon fuels accumulated on Earth over millions of years.

A large proportion of this energy on the planet's surface is converted into heat. It heats the earth and water, and from them the air is heated. Heat from the Sun determines ocean currents, the water cycle in nature, air currents, etc. The heat is gradually radiated into space and lost there. In the planet’s ecosystem, energy goes through a long and complex path of transformation, but only a small part of the amount received is used. As a result, the ecosystem works and does not pollute environment and uses a small part of the energy reaching the Earth. From this we can conclude that the constant flow of energy from the Sun to the Earth is constant and arrives in excess quantities.

Plants on Earth consume only 0.5 percent of the energy reaching the Earth. Therefore, even if humanity lives only on the energy of the sun, they will only consume a small fraction of it. The energy of the Sun on Earth is quite sufficient for the energy needs of civilization. At the same time, we will take only a small part of the energy, and this will not affect the biosphere in any way. The sun sends enormous amounts of energy to Earth. Within a few days, its quantity exceeds the energy potential of all proven fuel reserves. Even a third of this amount that reaches the Earth is thousands of times higher than all traditional energy sources.

Solar energy is environmentally friendly. Of course, nuclear reactions taking place in the Sun generate radioactive contamination. But it is at a safe distance from the Earth. But the combustion of hydrocarbons and nuclear power plants create pollution on Earth. In addition, the energy of the Sun is constant and present in excess quantities.

We can say that the energy of the sun is eternal. Some experts say that the star will go out in a few billion years. But what does this mean for us? After all, humans have existed for approximately 3 million years. So, the use of solar energy is not limited in time. Thanks to the energy that the Sun gives off, 2 cycles of substances occur on Earth. One of them is large (also called geological). It manifests itself in the circulation of the atmosphere and water masses. And also a small biological (also called biotic) cycle, which works on the basis of a large one. It consists in the cyclic redistribution of energy and substances within the boundaries of ecological systems. These cycles are interconnected and are a single process.

What are the problems with using solar energy?

It would seem that everything is fine and we need to switch to using solar energy. It turns out there are a number of problems. Which ones? The main problem is that the incoming energy is highly dissipated. Approximately 100-200 watts fall per square meter. The exact amount depends on the location of this place on Earth. In addition, the Sun shines during the day, and the power at this time reaches 400-900 watts per square meter. But at night there is no energy supplied, and in cloudy weather there is much less energy supplied. That is, at some moments you need to collect all this energy flow and accumulate it. And when sunlight does not fall on the ground, use the accumulated energy.

Collect energy from the sun in different ways. It is natural to collect heat to heat the coolant, and then use it in the home heating system or in the hot water supply. And another common way to convert solar energy is to generate electricity. All these installations are produced both factory-made and independently. Some craftsmen make heaters in an ordinary window of an apartment or house. This results in additional heating of the room. Collectors and solar systems are also common for generating electricity in private homes. However, the use of thermal collectors is limited by climatic conditions. And solar panels for converting solar energy into electricity still have low efficiency.

But in general, solar systems are a very promising area of ​​energy. As soon as the price of energy resources rises a little more, they will become in great demand. There are many areas on Earth where the sun shines almost constantly. These are steppes, deserts. By installing solar power plants there and generating electricity, you can develop this land and make it fertile. Energy will be spent on water supply and the needs of the population.

Excursion into the past

Once upon a time, in ancient times, pagans perceived the Sun as a deity. Of course, at that time there was no use of solar energy as such. It was something magical. But the first attempts to use solar energy have been made for quite some time. If you do not take into account the legend about the fleet burned with the help of concentrated solar energy in Ancient Greece, then the real use of solar energy began in the 19th-20th centuries. In 1839, the scientist Becquerel discovered the photovoltaic effect. A few decades later, Charles Fritts developed a solar module based on selenium coated with gold. The first solar panels that were produced in the 20th century had an efficiency of no more than 1%. But at that time it was a real breakthrough. As a result, new horizons for research and new discoveries have opened up for scientists.

Albert Einstein also made significant contributions to the development of solar energy. Of course, among his achievements the theory of relativity is most often mentioned. But he received his Nobel Prize for studying the phenomenon of the external photoelectric effect. The technology for producing solar panels for generating electricity is constantly being improved. Therefore, there is hope that we will soon witness new exciting discoveries in this area.

Areas of solar energy use

The scope of solar energy use is quite wide and is constantly expanding. Here we can even mention this simple thing like a summer shower with a tank at the top. It heats up from the sun and you can wash it. The use of solar systems for private homes just recently seemed like a fantasy, but today they have become a reality. Nowadays, many solar collectors are produced for heating domestic and industrial premises. There are already models that are capable of operating at subzero temperatures. In addition, there are all kinds of mobile devices for charging mobile gadgets, calculators, and other equipment powered by photovoltaic panels.

Solar energy is currently used in such areas of the national economy as:

• Energy supply of private houses, boarding houses, sanatoriums;
• Energy supply to settlements located far from urban infrastructure;
• Agriculture;
• Cosmonautics;
• Ecotourism;
• Street lighting, decorative lighting in summer cottages;
• Housing and communal services;
• Chargers.

Somewhat earlier, solar energy and related technologies were used only in astronautics and the military sphere. With the help of photocells, energy was supplied to satellites, various mobile stations, and the like. But gradually solar energy began to be used in everyday life and in production. Today you can often find solar systems in the southern regions. Most often they are used in the private sector, as well as in small tourism businesses (sanatoriums, holiday homes, etc.).

The sun's energy is just a stream of photons. And at the same time, this is one of the fundamental factors ensuring the very existence of life in our biosphere. Therefore, it is quite natural that sunlight is actively used by humans not only in the climatic aspect, but also as an alternative source of energy.

Where is solar energy used?

The scope of application of solar energy is very extensive, and every year it becomes larger. Thus, just recently, a country shower with a solar heater was perceived as something extraordinary, and the possibility of using sunlight for home electrical networks seemed fantastic. Today, you won’t surprise anyone not only with an autonomous solar station, but also with solar-powered mobile chargers and even small appliances (for example, watches) powered by the photovoltaic effect.

In general, the use of solar energy is in great demand in areas such as:

• Agriculture;
• Energy supply to sanatoriums and boarding houses;
• Space industry;
• Environmental protection and ecotourism;
• Electrification of remote and hard-to-reach regions;
• Street, garden and decorative lighting;
• Housing and communal services (DHW, house lighting);
• Mobile technology (solar-powered gadgets and charging modules).

Previously, solar energy was used mainly in the space industry (power supply for satellites, stations, etc.) and in industry, but over time, alternative energy began to be actively developed in everyday life. Some of the first facilities equipped with solar installations were southern boarding houses and sanatoriums, especially those located in secluded areas.

Solar installations and their advantages

The successful application of the first solar modules proved that energy sun rays has many advantages over traditional sources. Previously, the main advantages of solar power plants were only environmentally friendly and inexhaustible (as well as free) of sunlight.

But in fact, the list of advantages is much wider:

• Autonomy, since no external energy communications are required;
• Stable power supply; due to its specific nature, solar current is not subject to voltage surges;
• Cost-effective, since funds are spent only once, during installation of the installation;
• Solid service life (over 20 years);
• All-season use, solar installations operate effectively even in frost and cloudy weather (with a slight decrease in efficiency);
• Simplicity and ease of maintenance, since it is only necessary to occasionally clean the front sides of the panels from dirt.

The only drawback is the dependence on the sun and the fact that such installations do not work at night. But this problem is solved by connecting special batteries in which the solar energy generated during the day is accumulated.

Photoenergy

Photoenergy is one of two ways to use radiation from the sun. This is a direct current generated under the influence of sunlight. This transformation occurs in so-called photocells, which, in essence, are a two-layer structure of two semiconductors different types. The lower semiconductor is p-type (with a lack of electrons), the upper one is n-type with an excess of electrons.

The electrons of the n-conductor absorb the energy of the sun's rays falling on them and leave their orbits, and the energy impulse is sufficient for them to move into the zone of the p-conductor. This produces a directed electron flow called photocurrent. In other words, the entire structure works as a kind of electrodes in which electricity is generated under the influence of the sun.

Silicon is used to produce such photocells. This is explained by the fact that silicon, firstly, is widespread, and secondly, its industrial processing does not require large expenses.

Silicon photocells are:

• Monocrystalline. They are made from single crystals and have a uniform structure with a slightly higher efficiency (about 20%), but they are more expensive.
• Polycrystalline. They have an uneven structure due to the use of polycrystals and a slightly lower efficiency (15-18%), but are much cheaper than monovariants.
• Thin film. They are made by sputtering amorphous silicon onto a thin-film substrate. They are distinguished by a flexible structure and the lowest production cost, but have twice the dimensions compared to crystalline analogues of the same power.

The scope of application of each type of cell is very extensive and is determined by its operational features.

Solar collectors

Solar collectors are also used as solar energy converters, but their operating principle is completely different. They convert the incident light not into electrical energy, but into thermal energy due to heating of the coolant liquid. They are used either for hot water supply or for heating houses. The main element of any collector is an absorber, also known as a heat sink. The absorber is either a flat plate or a tubular evacuated system, inside which a coolant circulates (this is either plain water or antifreeze). Moreover, the absorber must be painted black with a special paint to increase absorption coefficients.

It is based on the type of absorbers that collectors are divided into flat and vacuum. For flat ones, the heat absorber is made in the form of a metal plate, to which a metal coil with coolant is soldered from below. Vacuum absorbers are made of several glass tubes connected to each other at the ends. The tubes are made double, a vacuum is created between the walls, and a rod with coolant is placed inside. All rods communicate with each other through special connectors at the pipe joints.

Absorbers of both types are placed in a durable, lightweight housing (usually made of aluminum or impact-resistant plastic) and are reliably thermally insulated from the walls. The front side of the case is covered with transparent shock-resistant glass with maximum permeability for photons. This ensures better absorption of solar energy.

Features of operation

The operating principle of both types of collectors is similar. Heating up in the collector to high temperatures, the coolant passes through the connecting hoses into the heat exchange tank, which is filled with water. It passes through the tank through a serpentine tube, giving off its heat to the water. The cooled coolant leaves the tank and is fed back into the collector. In essence, this is a kind of “solar” boiler,” only instead of a heating coil, a coil in the tank is used, and instead of an electrical network, sunlight is used.

Design differences also determine the difference in the use of vacuum and flat-plate collectors. The use of solar radiation using vacuum models is possible all year round, including in winter and in the off-season. Flat options work better in summer period. However, they are cheaper and simpler than vacuum ones, so they are optimally suited for seasonal purposes.

Solar energy in cities (eco-houses)

Solar energy is actively used not only for private houses, but also for urban buildings. How does a person use solar energy in megacities, it’s not difficult to guess. It is also used for heating and hot water supply of buildings, often for entire blocks.

IN recent years the concepts of eco-houses that operate entirely on alternative sources energy. They use combined systems to efficiently obtain solar, wind and thermal energy from the earth. Often such houses not only fully cover their energy needs, but also transfer the surplus to city networks. Moreover, quite recently projects of such eco-buildings have appeared in Russia.

Solar stations and their types

In the southern regions with high insolation, not just individual solar power plants are built, but entire stations that generate energy on an industrial scale. The amount of solar energy produced by them is very large and many countries with a suitable climate have already begun a gradual transition of the entire energy system to this alternative option. Based on the principle, the stations are divided into photothermal and photoelectric. The former work using the collector method and supply homes with heated water for hot water supply, while the latter directly generate electricity.

There are several types of solar stations:

• Tower. Allows you to obtain superheated water steam supplied to generators. A tower with a water reservoir is located in the center of the station; heliostats (mirror) are placed around it, which focus the rays on the reservoir. These are quite effective stations, their main drawback is the difficulty of accurately positioning the mirrors.
• Disc-shaped. They consist of a solar energy receiver and a reflector. A reflector is a dish-shaped mirror that concentrates radiation on the receiver. Such solar energy concentrators are located at a short distance from the receiver, and their number is determined by the required power of the installation.
• Parabolic. Tubes with a coolant (usually oil) are placed at the focus of a long parabolic mirror. The heated oil gives off heat to the water, which boils and rotates the generators.
• Aerostatic. In fact, these are the most efficient and mobile solar stations on Earth. Their main element is a balloon with a photovoltaic layer filled with water vapor. It rises high into the atmosphere (usually above the clouds). The heated steam from the ball is supplied to the turbine through a flexible steam line, condenses at the outlet and the water is pumped back into the ball. Once in the ball, the water evaporates and the cycle continues.
• On photo batteries. These are already familiar solar-powered installations that are used for private homes. They provide electricity and water heating in the required volumes.

Today, various types of solar stations (including combined ones, combining several types) are playing an increasingly important role in the energy production of many countries. And some states are restructuring their energy sector in such a way that in a few years they will almost completely switch to alternative systems.

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“Report on the topic “Use of solar energy on earth””

For many years, fire was maintained by burning plant energy sources (wood, shrubs, reeds, grass, dry algae, etc.), and then it was discovered that it was possible to use fossil substances to maintain fire: coal, oil, shale, peat.

The wonderful myth of Prometheus, who gave people fire, appeared in Ancient Greece significantly later than that, as in many parts of the world, methods of quite sophisticated handling of fire, its production and extinguishing, preservation of fire and rational use of fuel have been mastered.

It is now known that wood is solar energy accumulated through photosynthesis. When every kilogram of dry wood is burned, about 20,000 kJ of heat is released, the calorific value of brown coal is approximately 13,000 kJ/kg, anthracite 25,000 kJ/kg, oil and petroleum products 42,000 kJ/kg, and natural gas 45,000 kJ/kg . Hydrogen has the highest calorific value of 120,000 kJ/kg.

Humanity needs energy, and the need for it increases every year. At the same time, the reserves of traditional natural fuels (oil, coal, gas, etc.) are finite. There are also finite reserves of nuclear fuel - uranium and thorium, from which plutonium can be obtained in breeder reactors. The reserves of thermonuclear fuel - hydrogen - are practically inexhaustible, but controlled thermonuclear reactions have not yet been mastered, and it is not known when they will be used for industrial production of energy in its pure form, i.e. without the participation of fission reactors in this process. In connection with these problems, the use of non-traditional energy resources, primarily solar, wind, geothermal energy, along with the introduction of energy-saving technologies, is becoming increasingly necessary.

Since ancient times, humanity has used solar energy. Thanks to it, life on our planet is supported. The impact of sunlight on the surface of our rotating planet leads to uneven heating of the water surface of the oceans, seas, rivers, lakes and continental land. The resulting differences in atmospheric pressure, which set air masses in motion, contribute to the creation of living conditions for diverse species of flora and fauna. In fact, the sun with its energy is the source of life.

Recently, technologies have been developed to use this endless energy, which can easily replace traditional energy sources (coal, gas, oil), which are expensive to use in different climatic conditions. The use of solar installations has a number of advantages that are incomparable with other energy sources. Using some of the advantages, the company Sveton http://220-on.ru/ successfully solves the problem of ensuring a comfortable quality of life through installations of autonomous power supply and uninterruptible power supply systems for owners of country real estate.

Key Benefits

Inexhaustible reserves of energy, which are given practically for nothing. The installations used are completely safe and autonomous. It can be noted that they are cost-effective, since only installation equipment is purchased. In addition, the stability of the power supply is ensured without any voltage surges. We will also add such indicators as long service life and ease of use.

If just a few years ago solar heat was mainly used for natural heating of water under the rays of the sun, now it is possible to list a number of areas of human activity where solar energy is directly used.

Applications of solar energy

Firstly, it is in the agricultural sector of the national economy - for generating electricity, heating greenhouses, greenhouses, premises and buildings.

Secondly, to provide electricity to medical, healthcare and sports institutions.

Thirdly, in aviation and spacecraft.

Fourthly, as light sources at night in cities.

Fifthly, in the supply of electricity to populated areas.

Sixthly, in providing power supply to equipment for supplying hot water to residential premises.

Seventhly, to provide for household needs.

There are passive and active ways to convert sunlight into thermal energy.

Passive ways to convert solar energy into thermal energy

This method is based on the fact that the local landscape and climate are taken into account when constructing buildings. During their construction, the peculiarities of the climate are studied, which makes it possible to use such resources of building materials and technologies in order to obtain the maximum effect (especially in hot countries) from the facility under construction in terms of energy consumption and ensuring the environmental safety of the building. Therefore, in hot countries they strive to effectively use local conditions for such buildings.

Active ways to use solar energy

Special collectors and photocells, pumps, batteries, and various heating pipelines are the tools through which solar energy is converted. Let's look at solar collectors that convert the sun's energy in several ways, which determine the appropriate type of collector.

1. For domestic needs, a flat collector is widely used, which heats water under the influence of sunlight in appropriate containers.

2. For high temperatures, vacuum solar collectors are used, which operate by heating water passing through glass tubes located in an area illuminated by the sun. Such installations are used in domestic conditions.

3. Drying installations use air-type collectors that heat air masses under the sun's rays.

4. Integrated type collectors, in which water heated in domestic systems is collected into a common container and subsequently used for various needs, for example, for gas boilers.

A photocell (solar cell, battery) is a semiconductor in which light generates current without any chemical reactions, providing a fairly long service life. Such solar cells (batteries) are widely used in the space field, but can be widely used in others.

Solar panels are very economical and are becoming increasingly popular in domestic environments. For example, farmers and household plots are increasingly showing interest in them. In addition, today hard-to-reach places in new regions and agricultural lands are being developed, especially in the Asian part of our country. Automobile and aviation transport also has a chance to use solar panels in the future. It is also necessary to highlight such quality as the environmental friendliness of these systems, which do not harm health.

The sun is a natural huge source of energy. Hundreds of different processes take place every minute inside this gas ball. Without the Sun, life on Earth is impossible, since it is the source of energy for all living organisms. All earthly natural processes are carried out thanks to solar energy. Atmospheric circulation, water cycle, photosynthesis, heat regulation on the planet - all this would be impossible without the Sun. The use of solar energy on Earth is as common as breathing in and out for humans. But it can give humanity even more. It can be successfully used to produce industrial energy, thermal or electrical.

The potential of solar energy

Developments on the use of solar energy began in the 20th century. Since then, hundreds of studies have been conducted by scientists from all over the world. They have proven that the efficiency of using solar energy can be very, very high. This source can provide energy supply to the entire planet much better than all currently existing resources combined. Moreover, this type of energy is publicly available and free.

Harnessing solar energy

The reserves of natural resources capable of providing energy supply on Earth are decreasing every day. Therefore, active development is currently underway in various ways use of solar energy. This resource is an excellent alternative to traditional sources. Therefore, research in this area is incredibly important for society.

The achievements that exist at the moment have made it possible to create systems for using solar energy, which are made into two types:

• Active (photovoltaic systems, solar power plants and collectors).
• Passive (selection of building materials and design of premises for maximum use of solar energy).

The conversion and use of solar energy in this way has made it possible to use an inexhaustible resource with high productivity and return on investment.

Operating principle of passive systems

There are several types of passive use of solar energy. Most of them are incredibly easy to use, yet quite effective. There are also more sophisticated options that help you get more benefits. For example:

• The first thing that comes to mind is the container in which water is stored. If you paint it in dark shade, then in this simple way solar energy will be converted into thermal energy, and the water will heat up.
• The following option is not possible to an ordinary person independently, since it requires a scrupulous analysis by a specialist. This technology should be taken into account at the stage of design and construction of a house. Based on climatic conditions, the building is designed in such a way that it itself acts as a solar collector. After which they are selected necessary materials, promoting maximum accumulation of solar energy.

Thanks to such methods, it becomes possible to use solar energy for heating and lighting of premises. Also, such developments contribute to energy saving. Since such a design can not only convert solar energy, but also retain heat inside the building, which can also significantly reduce costs.

Ways to actively use solar energy

The basis of this principle of energy supply are collectors. Such equipment absorbs energy and converts it into heat, which can be used to heat a house or heat water, and also converts solar energy into electrical energy. Collectors are widely used both industrially and in private areas and agriculture.

In addition to collectors, another equipment of the active system can be called panels with photocells. This device allows you to use solar energy at home and on an industrial scale. Such panels are very simple, low maintenance and durable.

Solar power plants are also a way to actively use solar energy. They are suitable only for large-scale conversion of radiation into thermal or electrical energy. In recent years, they have significantly gained popularity in the world and developments in this area make it possible to expand the capabilities and number of such stations.

Speaking about the fact that solar energy helps to save on the use of traditional resources, it is worth noting that such an advantage will be truly useful for people who have their own private plots. Owning your own home makes it possible to install energy conversion equipment that can satisfy, even if not completely, at least part of your energy needs. This will help to significantly reduce the consumption of centralized energy supply and reduce costs.

Solar energy is an excellent source for the following processes:

• Passive heating and cooling of the home.

We should not forget that the Sun already warms everything that exists on Earth, and your home is no exception. Therefore, it is possible to enhance the beneficial effects by making certain amendments at the construction stage and using special techniques. Thus, you will get a house with much more comfortable thermal regulation without much investment.

• Heating water using solar energy.

Using solar energy to heat water is the simplest and cheapest method available to humans. Such equipment can be purchased at reasonable prices. At the same time, they will be able to pay for themselves quickly enough, significantly reducing the cost of centralized energy supply.

• Street lighting.

This is the easiest and cheapest way to use solar energy. Special devices that absorb solar radiation during the day and illuminate areas at night are very popular among owners of private houses even now.

The solar panel, unfortunately, is not universally available. Its cost is quite high, but at the same time, it is a convenient and profitable energy resource that can be successfully used in Russian latitudes. But if your financial situation does not allow you to make such an expensive purchase, you can create similar panels yourself.

How to do this?

• First of all, you will need solar photocells. On average, one panel will require about 36 pieces. It is better to choose elements based on single crystals, as they have a higher efficiency and a longer service life.
• The panel itself is made from plywood sheet. A bottom is cut out of it, the size of which you determine based on the number of photocells. Next, the panel is placed in a frame made of bars.
• Then you need to make a substrate on which the photocells will be applied. This can be made from fiberboard.
• Next you need to make the holes. Be sure to make sure they are symmetrical.
• Next, the dyeing and drying procedure is carried out, which is repeated twice.
• After the substrate has dried, the elements are laid out on it and soldering is carried out. Important point– place them upside down.
• At the final stage, the photocells are laid out in rows, and then everything is connected into complexes. All this is ultimately secured with silicone.

In this simple way, you can create equipment with your own hands that allows you to use solar energy in your home. With a little effort and patience, you will succeed.

Use of solar energy in Russia

At what stage of development is alternative energy in Russia now? Unfortunately, at the present time this is happening at a very low level. The country is not yet realizing all its existing potential. This is quite strongly influenced by such an aspect as the presence of large reserves of minerals that are used for traditional energy supply.

However, successful use of solar energy in Russia is possible. Thanks to its huge area, which includes different climatic zones and topography, the country has the opportunity to actively develop the production of alternative energy. With a competent and comprehensive approach, it is possible to ensure a significant percentage of the total energy supply using solar energy.