Every day the amount of world reserves of coal, oil, gas, that is, everything that serves us as a source of energy today, is decreasing. And in the near future, humanity will come to the point where there will simply be no fossil fuels left. Therefore, all countries are actively seeking salvation from the catastrophe that is rapidly approaching us. And the first means of salvation that comes to mind is, of course, the energy of the sun, which has been used by people from time immemorial for drying clothes, lighting homes and cooking. This gave rise to one of the areas of alternative energy - solar energy.

The energy source for solar energy is the energy of sunlight, which is converted into heat or electricity using special structures. According to experts, in just one week, the earth’s surface receives an amount of energy from the sun that exceeds the energy of the world’s reserves of all types of fuel. And although the pace of development of this area of ​​alternative energy is steadily growing, solar energy still has not only advantages, but also disadvantages.

If the main advantages include accessibility, and most importantly the inexhaustibility of the energy source, then the disadvantages include:

• the need to accumulate energy received from the sun,
• significant cost of the equipment used,
• dependence on weather conditions and time of day,
• increase in atmospheric temperature above power plants, etc.

Numerical characteristics of solar radiation

There is such an indicator as the solar constant. Its value is 1367 W. This is exactly the amount of energy per 1 sq.m. planet Earth. But because of the atmosphere, about 20-25% less energy reaches the surface of the earth. Therefore, the value of solar energy per square meter, for example, at the equator is 1020 W. And taking into account the change of day and night, the change in the angle of the sun above the horizon, this figure decreases by about 3 times.

But where does this energy come from? Scientists first began to study this issue back in the 19th century, and the versions were completely different. Today, as a result of a huge number of studies, it is reliably known that the source of solar energy is the reaction of converting 4 hydrogen atoms into a helium nucleus. As a result of this process, a significant amount of energy is released. For example, the energy released during the transformation of 1 g. hydrogen is comparable to the energy released during the combustion of 15 tons of gasoline.

Solar Energy Conversion

We already know that the energy received from the sun must be converted into some other form. The need for this arises due to the fact that humanity does not yet have such devices that could consume solar energy in its pure form. Therefore, energy sources such as solar collectors and solar panels were developed. If the first is used to generate thermal energy, then the second produces electricity directly.

There are several ways to convert solar energy:

• photovoltaics;
• thermal air energy;
• solar thermal energy;
• using solar balloon power plants.

The most common method is photovoltaics. The principle of this conversion is the use of photovoltaic solar panels, or solar panels as they are also called, through which solar energy is converted into electrical energy. As a rule, such panels are made of silicon, and the thickness of their working surface is only a few tenths of a millimeter. They can be placed anywhere, there is only one condition - the presence of a large amount of sunlight. An excellent option for installing photographic plates on the roofs of residential buildings and public buildings.

In addition to the photographic plates discussed above, thin-film panels are used to convert the energy of solar radiation. They are distinguished by their even smaller thickness, which allows them to be installed anywhere, but a significant drawback of such panels is their low efficiency. It is for this reason that their installation will be justified only for large areas. Just for fun, the thin-film panel can even be placed on a laptop case or on a handbag.

In thermal air energy, solar energy is converted into the energy of air flow, which is then sent to a turbogenerator. But in the case of using solar balloon power plants, water vapor is generated inside the balloon. This effect is achieved by heating the surface of the balloon, on which a selective-absorbing coating is applied, by sunlight. The main advantage of this method is the sufficient supply of steam, which is enough to continue the operation of the power plant in bad weather and at night.

The principle of solar energy is to heat a surface that absorbs the sun's rays and focuses them for the subsequent use of the resulting heat. The simplest example is heating water, which can then be used for domestic needs, for example, to be supplied to sewers or batteries, while saving gas or other fuel. On an industrial scale, solar radiation energy obtained by this method is converted into electrical energy using heat engines. The construction of such combined power plants can last over 20 years, but the pace of development of solar energy is not decreasing, but, on the contrary, is steadily growing.

Where can solar energy be used?

Solar energy can be used in completely different areas - from the chemical industry to the automotive industry, from cooking to space heating. For example, the use of solar panels in the automotive industry dates back to 1955. This year was marked by the release of the first car that ran on solar batteries. Today, BMW, Toyota and other major companies produce such cars.

In everyday life, solar energy is used for heating rooms, for lighting and even for cooking. For example, solar ovens made of foil and cardboard, on the initiative of the UN, are actively used by refugees who were forced to leave their homes due to the difficult political situation. More complex solar furnaces are used for heat treatment and smelting of metals. One of the largest such furnaces is located in Uzbekistan.

The most interesting inventions on the use of solar energy include:

• A protective case for a phone with a photocell, which is also a charger.
• A backpack with a solar panel attached to it. It will allow you to charge not only your phone, but also your tablet and even your camera, in general, any electronics that has a USB input.
• Solar Bluetooth headphones.

And the most creative idea is clothes made from special fabric. A jacket, tie and even a swimsuit - all this can become not only an item in your wardrobe, but also a charger.

Development of alternative energy in the CIS countries

Alternative energy, including solar, is developing at a high rate not only in the USA, Europe or India, but also in the CIS countries, including Russia, Kazakhstan, and especially Ukraine. For example, the largest solar power plant in the former Soviet Union, Perovo, was built in Crimea. Its construction was completed in 2011. This power plant became the 3rd innovative project of the Austrian company Activ Solar. The peak power of Perovo is about 100 MW.

And in October of the same year, Activ Solar launched another solar power plant, Okhotnikovo, also in Crimea. Its power was 80 MW. Okhotnikovo also received the status of the largest, but in Central and Eastern Europe. We can say that alternative energy in Ukraine has taken a huge step towards safe and inexhaustible energy.

In Kazakhstan, the situation looks a little different. Basically, the development of alternative energy in this country occurs only in theory. The republic has enormous potential, but it has not yet been fully realized. Of course, the government is dealing with this issue, and even a plan has been developed for the development of alternative energy in Kazakhstan, but the share of energy obtained from renewable sources, in particular from the sun, will be no more than 1% in the country’s overall energy balance. By 2020, there are plans to launch only 4 solar power plants, the total capacity of which will be 77 MW.

Alternative energy in Russia is also developing at a considerable pace. But, as the Deputy Minister of Energy said, the focus in this area is mainly on the Far Eastern regions. For example, in Yakutia, the total output of 4 solar power plants operating in the most remote northern villages amounted to more than 50 thousand kWh. This allowed saving more than 14 tons of expensive diesel fuel. Another example of the use of solar energy is the multi-functional aviation complex under construction in the Lipetsk region. Electricity for its operation will be generated by the first solar power plant, also built in the Lipetsk region.

All this allows us to draw the following conclusion: today all countries, even not the most developed ones, strive to get as close as possible to the cherished goal: the use of alternative energy sources. After all, electricity consumption is growing every day, and the amount of harmful emissions into the environment is increasing every day. And many already understand that our future and the future of our planet depends only on us.

R. Abdullina

Ukraine relies on solar energy

Solar radiation is absorbed by the land surface, oceans (covering about 71% of the globe's surface) and the atmosphere. Absorption of solar energy through atmospheric convection, evaporation and condensation of water vapor drives the water cycle and controls winds. The sun's rays absorbed by the ocean and land maintain the average temperature on the Earth's surface, which is now 14 °C. Through plant photosynthesis, solar energy can be converted into chemical energy, which is stored in the form of food, wood, and biomass, which is eventually converted into fossil fuels.

Video on the topic

Prospects for use

Solar energy is a source of wind, water, sea heat, biomass, and also the cause of the formation of peat, brown and hard coal, oil and natural gas over thousands of years, but this energy is indirect and accumulated over thousands and millions of years. Solar energy can also be used directly as a source of electricity and heat. To do this, it is necessary to create devices that concentrate the energy of the Sun on small areas and in small volumes.

The total amount of solar energy absorbed by the atmosphere, land surface and ocean is approximately 3,850,000 exajoules (EJ) per year. In one hour, this provides more energy than the entire world used in the entire year 2002. Photosynthesis takes about 3,000 EJ per year to produce biomass. The amount of solar energy that reaches the surface of the earth is so large that in a year it will approximately double all the energy that can potentially be generated from all non-renewable sources: coal, oil, uranium ores.

The amount of solar energy that a person can potentially use is different from the amount of energy that is located near the earth's surface. Factors such as day and night cycles, cloud cover and available land surface reduce the amount of usable energy.

Geographical location affects energy potential, since areas closer to the equator receive more solar radiation. However, the use of photovoltaic devices, which can change their orientation in accordance with the position of the Sun in the sky, can significantly increase the potential of solar energy in areas distant from the equator.

The availability of land significantly influences the possible production of energy, since solar panels can only be installed on land that is suitable for this and is not used for other purposes. For example, a suitable place to install steel roof panels.

Solar systems are divided into active and passive, depending on the method of absorbing solar energy, processing it and distributing it.

Active solar technologies use photovoltaics, concentrated solar energy (English), solar collectors, pumps and fans to convert solar radiation into useful energy output. Passive solar technologies include the use of materials with favorable thermal characteristics, design of rooms with natural air circulation and favorable location of buildings relative to the position of the Sun. Active solar technologies increase energy supply, while passive solar technologies reduce the need for additional energy sources.

At this time, heating devices are operating that accumulate the energy of the Sun, as well as prototypes of electric motors and cars that use the energy of the Sun.

Solar energy is believed to make up no more than 1% of total energy use by the end of the century. Back in 1870, a solar seawater desalination plant was built in Chile, which produced up to 30 tons of fresh water per day and operated for more than 40 years. Thanks to the use of heterojunctions, the efficiency of solar cells already reaches 25%. The production of solar cells in the form of long polycrystalline silicon strips, which have an efficiency of more than 10%, has been established.

Thermal energy

Technologies that use thermal energy from the sun can be used for water heating, space heating, space cooling and process heat generation.

As of 2007, the total installed capacity of solar water heating systems was approximately 154 GW thermal. China is the world leader in this field, having installed 70 GW of thermal as of 2006 and planning to reach 210 GW of thermal by 2020. Israel and Cyprus lead the world in the use of solar water heating systems per capita with 90% of households having installed them. In the USA, Canada and Australia, solar water heaters are used primarily for heating swimming pools, with an installed thermal capacity of about 18 GW as of 2005.

Heating, cooling and ventilation

Cooking

Solar ovens use sunlight for cooking, drying and pasteurization. They can be divided into three broad categories: box cookers, panel cookers and reflector cookers. The simplest solar oven is the boxchast, which was first built by Horace Benedict de Saussure in 1767. A simple box oven consists of an insulated container with a transparent lid. It can be used effectively in partially cloudy skies and typically reaches temperatures of 90-150°C. A panel oven uses a reflective panel to direct the sun's rays onto an insulated container and achieve temperatures comparable to a box oven. Reflective ovens use different reflector geometries (dish, trough, Fresnel mirrors) to focus the rays onto the container. These ovens reach temperatures of 315°C, but require a direct beam and must be moved as the sun's position changes.

Process heat

Water treatment

Solar desalination can be used to convert salt or brackish water into potable water. The first example of such a transformation was recorded by Arab alchemists of the 16th century. The first large-scale solar desalination project was built in 1872 in the Chilean mining town of Las Salinas. The plant, which had a solar collector area of ​​4,700 m2, could produce up to 22,700 liters of drinking water and remained in operation for 40 years. Individual still designs include single-slope, double-slope (greenhouse or type), vertical, conical, inverted absorber, multi-wick, and multiple effect. . These desalination plants can operate in passive, active and hybrid modes. Double-slope Kazan units are the most cost-effective for decentralized household needs, while active multiple effect units are more suitable for large-scale projects.

Solar energy can be used at moderate rates to treat wastewater without the use of chemicals or electricity. Another environmental benefit is that algae live in such ponds and consume carbon dioxide through photosynthesis, although they can produce toxic substances that make the water unfit for consumption.

Power generation

Solar energy works by converting sunlight into electricity. This can happen either directly, using photovoltaics, or indirectly, using concentrated solar energy systems (English), in which lenses and mirrors collect sunlight from a large area into a thin beam, and a tracking mechanism tracks the position of the Sun. Photovoltaics converts light into electric current using the photoelectric effect.

Solar power is projected to become the largest source of electricity by 2050, with photovoltaics and concentrated solar power accounting for 16 and 11% of global electricity production, respectively.

Commercial concentrated solar power plants first appeared in the 1980s. After 1985 installation of this type of SEGS (English) in the Mojave Desert (California) 354 MW became the largest solar power plant in the world. Among other solar power plants of this type is SES Solnova (English)(150 MW) and SES Andasol (English)(100 MW), both in Spain. Among the largest photovoltaic power plants (English): Agua Caliente Solar Project (250 MW) in the USA, and Charanka Solar Park (221 MW) in India. Projects larger than 1 GW are in the development stage, but most photovoltaic installations, up to 5 kW, are small in size and located on rooftops. As of 2013, solar power accounted for less than 1% of the world's grid electricity.

Architecture and urban planning

The presence of sunlight has influenced the design of buildings from the very beginning of architectural history. Advanced solar architecture and urban planning techniques were pioneered by the ancient Greeks and Chinese, who oriented their homes to the south to provide light and heat.

Agriculture and crop production

see also

Notes

1. Smil (1991), p. 240
2. Radiation and light regime
3. Natural Forcing of the Climate System. Intergovernmental Panel on Climate Change. Retrieved September 29, 2007.
4. Somerville, Richard. Historical Overview of Climate Change Science (PDF). Intergovernmental Panel on Climate Change. Retrieved September 29, 2007.
5. Vermass, Wim. An Introduction to Photosynthesis and Its Applications. Arizona State University. Retrieved September 29, 2007.
6. Smil (2006), p. 12
7. http://www.nature.com/nature/journal/v443/n7107/full/443019a.html
8. Powering the Planet: Chemical challenges in solar energy utilization (PDF). Retrieved August 7, 2008.
9. Energy conversion by organisms photosynthetic. Food and Agriculture Organization of the United Nations. Retrieved May 25, 2008.
10. Exergy Flow Charts - GCEP. stanford.edu.
11. Archer, Cristina. Evaluation of Global Wind Power. Stanford. Retrieved June 3, 2008.
12. . Renewable and Appropriate Energy Laboratory. Retrieved December 6, 2012.
13. Total Primary Energy Consumption. Energy Information Administration. Retrieved June 30, 2013.
14. Total Electricity Consumption Net. Energy Information Administration. Retrieved June 30, 2013.
15. Energy and the challenge of sustainability (PDF). UN Development Program and World Energy Council(September 2000). Retrieved January 17, 2017.

Solar energy gives life to all life on Earth. Under its influence, water evaporates from the seas and oceans, turning into water drops, forming fogs and clouds. As a result, this moisture falls back onto the Earth, creating a constant cycle. Therefore, we constantly observe snow, rain, frost or dew. The huge heating system created by the sun allows for the most optimal distribution of heat over the surface of the Earth. To correctly understand and use these processes, it is necessary to imagine the source of the sun’s energy and what determines its influence on our planet.

Types of solar energy

The main type of energy released by the Sun is rightfully considered radiant energy, which has a direct impact on all the most important processes occurring on Earth. If we compare other earthly energy sources with it, their reserves are infinitely small and do not allow us to solve all problems.

Of all the stars, the Sun is closest to the Earth. In its structure, it is a gas ball, many times greater than the diameter and volume of our planet. Since the dimensions of the gas ball are quite arbitrary, the solar disk visible from the Earth is considered to be its boundaries.

Source and physical properties of solar energy

All processes occurring on the Sun can be observed only on its surface. However, the main reactions take place in its interior. Essentially, this is a giant nuclear power plant with a pressure of approximately 100 billion atmospheres. Here, under the conditions of complex nuclear reactions, hydrogen is converted into helium. It is these reactions that form the main source of energy from the sun. The internal temperature averages approximately 16 million degrees.

The gas raging inside the Sun not only has an ultra-high temperature, but is also extremely heavy, with a density many times higher than the average solar density. At the same time, X-rays appear, which, as they approach the Earth, increase their wavelength and reduce their oscillation frequency. Thus, they gradually become visible and ultraviolet light.

As you move away from the center, the nature of the radiant energy changes, affecting the temperature. There is a gradual decrease, first to 150 thousand degrees. From Earth, only the outer shell of the sun, the so-called photosphere, is clearly visible. Its thickness is approximately 300 km, and the temperature of the upper layer drops to 5700 degrees.

Above the photosphere is the solar atmosphere, which consists of two parts. The lower layer is called the chromosphere, and the upper layer, which has no boundaries, is the solar corona. Here the gases are heated to several million degrees under the influence of shock waves of monstrous force.

In recent years, scientists have been especially interested in alternative energy sources. Oil and gas will run out sooner or later, so we have to think about how we will survive in this situation now. In Europe, wind turbines are actively used, someone is trying to extract energy from the ocean, and we will talk about solar energy. After all, the star that we see in the sky almost every day can help us save and improve the environmental situation. The importance of the sun for the Earth is difficult to overestimate - it provides warmth, light and allows all life on the planet to function. So why not find another use for it?

A little history

In the mid-19th century, physicist Alexandre Edmond Becquerel discovered the photovoltaic effect. And by the end of the century, Charles Fritts created the first device capable of converting solar energy into electricity. For this purpose, selenium coated with a thin layer of gold was used. The effect was weak, but it is this invention that is often associated with the beginning of the era of solar energy. Some scientists do not agree with this formulation. They call the world famous scientist Albert Einstein the founder of the era of solar energy. In 1921 he received the Nobel Prize for his explanation of the laws of the external photoelectric effect.

It would seem that solar energy is a promising path of development. But there are many obstacles to its entry into every home - mainly economic and environmental. We will find out below what the cost of solar panels is, what harm they can cause to the environment and what other methods of generating energy exist.

Saving methods

The most pressing task associated with taming the energy of the sun is not only its receipt, but also its accumulation. And this is precisely what is most difficult. Currently, scientists have developed only 3 methods for fully taming solar energy.

The first is based on the use of a parabolic mirror and is a bit like playing with a magnifying glass, which is familiar to everyone from childhood. Light passes through the lens, converging at one point. If you put a piece of paper in this place, it will catch fire, since the temperature of the crossed rays of the sun is incredibly high. A parabolic mirror is a concave disk that resembles a shallow bowl. This mirror, unlike a magnifying glass, does not transmit, but reflects sunlight, collecting it at one point, which is usually directed at a black pipe with water. This color is used because it absorbs light best. The water in the pipe is heated by the sun's rays and can be used to generate electricity or for heating small houses.

Flat heater

This method uses a completely different system. The solar energy receiver looks like a multilayer structure. The principle of its operation looks like this.

Passing through the glass, the rays hit the darkened metal, which is known to absorb light better. Solar radiation turns into and heats the water, which is located under the iron plate. Then everything happens as in the first method. The heated water could be used either for space heating or to generate electrical energy. True, the effectiveness of this method is not so high that it can be used everywhere.

As a rule, the solar energy obtained in this way is heat. To generate electricity, the third method is much more often used.

Solar cells

We are most familiar with this method of obtaining energy. It involves the use of various batteries or solar panels, which can be found on the roofs of many modern houses. This method is more complicated than previously described, but is much more promising. It is this that makes it possible for the sun to be converted into electricity on an industrial scale.

Special panels designed to catch rays are made from enriched silicon crystals. Sunlight hitting them knocks the electron out of orbit. Another immediately strives to take its place, thus creating a continuous moving chain, which creates a current. If necessary, it is immediately used to power devices or accumulated in the form of electricity in special batteries.

The popularity of this method is justified by the fact that it allows you to get more than 120 W from just one square meter of solar battery. At the same time, the panels have a relatively small thickness, which allows them to be placed almost anywhere.

Types of Silicon Panels

There are several types of solar panels. The first ones are made using monocrystalline silicon. Their efficiency is approximately 15%. These are the most expensive.

The efficiency of elements made from polycrystalline silicon reaches 11%. They cost less because the material for them is obtained using simplified technology. The third type is the most economical and has minimal efficiency. These are panels made of amorphous silicon, that is, non-crystalline. In addition to low efficiency, they have another significant drawback - fragility.

To increase efficiency, some manufacturers use both sides of the solar panel - back and front. This allows you to capture light in large volumes and increases the amount of energy received by 15-20%.

Domestic producers

Solar energy on Earth is becoming increasingly widespread. Even in our country they are interested in studying this industry. Despite the fact that the development of alternative energy is not very active in Russia, some success has been achieved. Currently, several organizations are engaged in the creation of panels for generating solar energy - mainly scientific institutes of various fields and factories for the production of electrical equipment.

1. NPF "Quark"
2. OJSC Kovrov Mechanical Plant.
3. All-Russian Research Institute for Electrification of Agriculture.
4. NPO Mashinostroeniya.
5. JSC VIEN.
6. OJSC Ryazan Metal-Ceramic Devices Plant.
7. JSC Pravdinsky Experimental Plant of Power Sources "Posit".

This is only a small part of the enterprises taking an active part in the development of alternative

Environmental impact

The abandonment of coal and oil energy sources is not only due to the fact that these resources will sooner or later run out. The fact is that they greatly harm the environment - they pollute the soil, air and water, contribute to the development of diseases in people and reduce immunity. That is why alternative energy sources must be safe from an environmental point of view.

Silicon, which is used to produce solar cells, is itself safe because it is a natural material. But after cleaning it, waste remains. They can cause harm to humans and the environment if used incorrectly.

In addition, in an area completely filled with solar panels, natural lighting may be disrupted. This will lead to changes in the existing ecosystem. But in general, the environmental impact of devices designed to convert solar energy is minimal.

Economical

The highest costs are associated with the high cost of raw materials. As we have already found out, special panels are created using silicon. Despite the fact that this mineral is widespread in nature, its extraction poses great challenges. The fact is that silicon, which makes up more than a quarter of the mass of the earth's crust, is not suitable for the production of solar cells. For these purposes, only the purest material obtained industrially is suitable. Unfortunately, it is extremely difficult to obtain pure silicon from sand.

The price of this resource is comparable to uranium used in nuclear power plants. This is why the cost of solar panels currently remains at a fairly high level.

Modern technologies

The first attempts to tame solar energy appeared quite a long time ago. Since then, many scientists have been actively searching for the most effective equipment. It should not only be cost-effective, but also compact. Its efficiency should tend to the maximum.

The first steps towards an ideal device for receiving and converting solar energy were made with the invention of silicon batteries. Of course, the price is quite high, but the panels can be placed on the roofs and walls of houses, where they will not disturb anyone. And the effectiveness of such batteries is undeniable.

But the best way to increase the popularity of solar energy is to make it cheaper. German scientists have already proposed replacing silicon with synthetic fibers that can be integrated into fabric or other materials. The efficiency of such a solar battery is not very high. But a shirt interspersed with synthetic fibers can at least provide electricity to a smartphone or player. Work is also being actively carried out in the field of nanotechnology. It is likely that they will allow the sun to become the most popular source of energy in this century. Specialists from Scates AS from Norway have already stated that nanotechnology will reduce the cost of solar panels by 2 times.

Solar energy for home

Many people probably dream of housing that will provide for itself: there is no dependence on centralized heating, no difficulties with paying bills and no harm to the environment. Already now, in many countries, housing is being actively built that consumes only energy obtained from alternative sources. A striking example is the so-called solar house.

During the construction process, it will require larger investments than the traditional one. But after several years of operation, all costs will be recouped - you will not have to pay for heating, hot water and electricity. In a solar house, all these communications are tied to special photovoltaic panels placed on the roof. Moreover, the energy resources obtained in this way are not only spent on current needs, but also accumulated for use at night and in cloudy weather.

Currently, the construction of such houses is carried out not only in countries close to the equator, where it is easiest to extract solar energy. They are also being built in Canada, Finland and Sweden.

Advantages and disadvantages

The development of technologies that allow the widespread use of solar energy could be carried out more actively. But there are certain reasons why this is still not a priority. As we said above, the production of panels produces substances harmful to the environment. In addition, the finished equipment contains gallium, arsenic, cadmium and lead.

The need for recycling photovoltaic panels also raises many questions. After 50 years of operation they will become unfit for service and will have to be destroyed somehow. Won't this cause colossal harm to nature? It is also worth considering that solar energy is a fickle resource, the efficiency of which depends on the time of day and weather. And this is a significant drawback.

But, of course, there are advantages. Solar energy can be produced almost anywhere on Earth, and the equipment for obtaining and converting it can be so small that it fits on the back of a smartphone. What is also important is that it is a renewable resource, meaning the amount of solar energy will remain unchanged for at least thousands of years.

Prospects

The development of solar energy technologies should lead to lower costs for creating cells. Glass panels that can be installed on windows are already appearing. The development of nanotechnology has made it possible to invent a paint that will be sprayed onto solar panels and can replace the silicon layer. If the cost of solar energy actually decreases several times, its popularity will also increase many times over.

Creating small panels for individual use will allow people to use solar energy in any environment - at home, in the car or even outside the city. Thanks to their distribution, the load on centralized power grids will be reduced, since people will be able to charge small electronics on their own.

Shell experts believe that by 2040, about half of the world's energy will be generated from renewable resources. Already in Germany, solar energy consumption is actively growing, and battery capacity is more than 35 Gigawatts. Japan is also actively developing this industry. These two countries are the leaders in solar energy consumption in the world. The United States will probably soon join them.

Other alternative energy sources

Scientists continue to puzzle over what else can be used to generate electricity or heat. Let us give examples of the most promising alternative energy sources.

Wind turbines can now be found in almost every country. Even on the streets of many Russian cities, lanterns are installed that provide themselves with electricity using wind energy. Surely their cost is higher than average, but over time they will make up for this difference.

Quite a long time ago, a technology was invented that makes it possible to obtain energy using the difference in water temperatures on the surface of the ocean and at depth. China is actively planning to develop this area. In the coming years, they are planning to build the largest power plant using this technology off the coast of China. There are other ways to use the sea. For example, in Australia they are planning to create a power plant that generates energy from the power of currents.

There are many others or heat. But compared to many other options, solar energy is a truly promising direction in the development of science.

The sun is one of the renewable alternative energy sources. Today, alternative heat sources are widely used in agriculture and for the domestic needs of the population.

The use of solar energy on earth plays an important role in human life. Using its heat, the sun, as a source of energy, heats the entire surface of our planet. Thanks to its thermal power, winds blow, seas, rivers, lakes heat up, and all life on earth exists.

People began to use renewable heat sources many years ago, when modern technologies did not yet exist. The sun is the most accessible supplier of thermal energy on earth today.

Areas of solar energy use

Every year the use of solar energy is gaining more and more popularity. Just a few years ago it was used to heat water for country houses and summer showers, and now renewable heat sources are used to generate electricity and hot water supply to residential buildings and industrial facilities.

Today, renewable heat sources are used in the following areas:

• in agriculture, for the purpose of power supply and heating of greenhouses, hangars and other buildings;
• for power supply of sports facilities and medical institutions;
• in the field of aviation and space industry;
• in lighting streets, parks, and other city facilities;
• for electrification of populated areas;
• for heating, electricity and hot water supply of residential buildings;
• for household needs.

Features of application

The light that the sun emits on earth is converted into thermal energy using passive as well as active systems. Passive systems include buildings in the construction of which building materials are used that most effectively absorb solar radiation energy. In turn, active systems include collectors that convert solar radiation into energy, as well as photocells that convert it into electricity. Let's take a closer look at how to properly use renewable heat sources.

Passive systems

Such systems include solar buildings. These are buildings built taking into account all the features of the local climatic zone. For their construction, materials are used that make it possible to make maximum use of all thermal energy for heating, cooling, and lighting of residential and industrial premises. These include the following construction technologies and materials: insulation, wooden floors, light-absorbing surfaces, and the orientation of the building to the south.

Such solar systems allow for maximum use of solar energy, and they quickly pay back the costs of their construction by reducing energy costs. They are environmentally friendly and also allow you to create energy independence. It is because of this that the use of such technologies is very promising.

Active systems

This group includes collectors, batteries, pumps, pipelines for heat supply and hot water supply in the home. The first ones are installed directly on the roofs of houses, and the rest are located in basements to be used for hot water supply and heating.

Solar photocells

In order to more efficiently realize all solar energy, solar energy sources such as photocells, or as they are also called, solar cells, are used. On their surface they have semiconductors, which, when exposed to the rays of the sun, begin to move, and thereby generate electric current. This principle of current generation does not contain any chemical reactions, which allows photocells to operate for a long time.

Such photovoltaic converters as solar energy sources are easy to use as they are light in weight, easy to maintain and are also very efficient in utilizing solar power.

Today, solar panels, as a source of solar energy on earth, are used to generate hot water, heating and electricity in warm countries such as Turkey, Egypt and Asian countries. In our region, the sun is used as an energy source to supply electricity to autonomous power systems, low-power electronics and aircraft drives.

Solar collectors

The use of solar energy by collectors is that they convert radiation into heat. They are divided into the following main groups:

• Flat solar collectors. They are the most common. They are convenient to use for domestic heating needs, as well as for heating water for hot water supply;
• Vacuum collectors. They are used for domestic needs when high temperature water is needed. They consist of several glass tubes, passing through which the rays of the sun heat them, and they, in turn, give off heat to the water;
• Airborne solar collectors. They are used for air heating, air mass recovery and drying installations;
• Integrated collectors. The simplest models. They are used to preheat water, for example, for gas boilers. In everyday life, heated water is collected in a special tank - storage tanks and is then used for various needs.

The use of solar energy by collectors is carried out by accumulating it in so-called modules. They are installed on the roof of buildings and consist of glass tubes and plates, which are painted black in order to absorb more sunlight.

Solar collectors are used to heat water for hot water supply and heating of residential buildings.

Advantages of solar installations

• they are completely free and inexhaustible;
• are completely safe to use;
• autonomous;
• economical, since funds are spent only on the purchase of equipment for installations;
• their use guarantees the absence of power surges, as well as stability in the power supply;
• durable;
• easy to use and maintain.

The use of solar energy using such installations is gaining popularity every year. Solar panels make it possible to save a lot of money on heating and hot water supply; moreover, they are environmentally friendly and do not harm human health.