Homemade solar panel. Do-it-yourself solar power plant. We combine cells into one power system

Ecology of consumption. Life hack: Independence from energy and rising prices for it, be it thermal or electric. Solar panels will come to the rescue homemade windmills- one of the types of alternative sources of electricity

What does being a farmer mean to you? For me this is independence. Independence from various types of sanctions imposed different countries. Independence from rising food prices, since everything can be grown on your own farm. And, of course, this is independence from energy and rising prices for it, be it thermal or electric. In one of my articles, I wrote about how to build a biogas plant with your own hands, but it is suitable for those farmers who raise livestock, but what about those farmers who are engaged in vegetable growing or crop production?

Solar panels and homemade windmills will come to the rescue - one of the types of alternative sources of electricity. In my opinion, everything should be together. A windmill will charge the batteries when there is wind but no sunlight, and a solar panel does the opposite.

Operating principle of solar panels:

To understand how to assemble solar panels with your own hands, you need to understand their operating principle. This will allow you to select the appropriate material when purchasing. I think you need to know the following:

• Solar batteries operate using photocells, which can be monocrystalline or polycrystalline. Very often photovoltaic cells are called solar cells.
• It is unlikely that you will be able to assemble solar cells yourself, so you will have to buy them in any case. I looked for them in Russia, but unfortunately now everything is made in China.

The video below is an excerpt from a science program about solar panels, it tells a little history and how solar cells work. At the end of the article there will be detailed video on how to assemble a solar panel with your own hands.

After you learned from the video about the principle of operation of a solar battery, we can summarize some results:

1. Monocrystalline solar cells have an efficiency of about 13%, but it is more profitable only when the number of sunny days is high enough.
2. In Russia, I think it is not profitable to install these panels, so there are polycrystalline solar cells, their efficiency is approximately 7%, but they work better in cloudy conditions and little sunny days.
3. Now there are technologies that make it possible to make a photocell with an efficiency of more than 40%.
4. Approximately one photocell will produce 2.7 watts.
5. The price for polycrystalline and monocrystalline solar cells is basically the same, and it is also the same for solar panels.

You need to understand how much power you need and, based on this, calculate the required number of solar panels, but we’ll talk about this in future articles. It is important to know that solar panels can be used directly, so if you need to boil water in a 2kW kettle, you will need 20 100W panels. But if you use batteries, you can get by with 3-5 batteries, which will charge the battery after the kettle boils water.

I would like to note that batteries often cost as much as the panels themselves. If you use solar panels for lighting, you can get by with a 200 W panel and install energy-saving light bulbs in your house.

Assembling solar panels with your own hands

Before assembling solar panels with your own hands, you will need to make a frame for the battery. Plexiglas is used as a protective layer and a transparent surface in the frame; ordinary glass can also be used, but it is not so reliable. Aluminum corners are used for the body.

It is IMPORTANT to pay attention to soldering the solar cells into the circuit; this determines how well the solar panel will work. Photocells come with soldered wires, which will make the task easier, but you will have to solder in any case. Flux and solder are pre-applied.

To learn how to assemble a solar panel with your own hands, watch the video below.

A little economics about solar panels and the profitability of assembling them yourself

Having searched on the Internet for photocells for assembling solar panels in order to buy them in Russia, I found them for 3200 rubles for 38 pieces. I consider this not profitable, since now there are panels for 4500 rubles, a difference of 1300 will reduce your time and effort.

But if you look for Chinese solar cells, you can find 4,500 rubles for 100 pieces. From 100 pieces you can already assemble two 100 W panels. In this case, the benefit of purchasing photocells is obvious. I would like to draw your attention to the fact that the video below shows the assembly of photocells, the size of which is 125*63. On the Internet I found Chinese solar cells measuring 156*156, with their help you can assemble 4 solar panels of 100 W each.

As promised, a video on how to assemble a solar panel with your own hands. The principle of soldering and sealing is shown in great detail.SUBSCRIBE to OUR YouTube channel Ekonet.ru, which allows you to watch online, download free videos from YouTube about human health and rejuvenation. Love for others and for yourself,how the feeling of high vibrations is an important factor in healing - website

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Hydrocarbons have been and remain the main source of energy, but increasingly humanity is turning to renewable and environmentally friendly resources. This has caused increased interest in solar panels and generators.

However, many are hesitant to install a solar system due to the high cost of equipping the complex. You can make your products cheaper if you start creating them yourself. Do you doubt your own abilities?

We will tell you how to make a solar battery with your own hands using available components. In the article you will find all the necessary information in order to calculate the solar system, select the components of the complex, and assemble and install the photopanel.

According to statistics, an adult uses about a dozen different devices that operate from the network every day. Although electricity is considered a relatively environmentally friendly source of energy, this is an illusion, because its production uses polluting resources.

What components are needed and where to buy them

The main part is a solar photopanel. Typically, silicon wafers are purchased online and delivered from China or the USA. This is due to the high price of domestically produced components.

The cost of domestic plates is so high that it is more profitable to order on eBay. As for defects, out of 100 plates only 2-4 are unusable. If you order Chinese plates, the risks are higher, because... the quality leaves much to be desired. The only advantage is the price.

A ready-made panel is much more convenient to use, but also three times more expensive, so it’s better to look for components and assemble the device yourself

The remaining components can be purchased at any electrical goods store. You will also need tin solder, frame, glass, film, tape and a marking pencil.

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There is probably no person who would not like to become more independent. Possibility of complete control own time, traveling without knowing borders and distances, not thinking about housing and financial problems - this is what gives you a feeling of real freedom. Today we will talk about how, using solar radiation, you can relieve yourself of the burden of energy dependence. As you guessed, we will talk about solar panels. And to be more precise, about whether it is possible to build a real one with your own hands solar power plant.

History of creation and prospects for use

Humanity has been nurturing the idea of ​​converting solar energy into electricity for a long time. Solar thermal installations were the first to appear, in which steam superheated by concentrated solar rays rotated generator turbines. Direct conversion became possible only in the mid-19th century, after the Frenchman Alexandre Edmond Baccarelle discovered the photoelectric effect. Attempts to create an operating solar cell based on this phenomenon were crowned with success only half a century later, in the laboratory of the outstanding Russian scientist Alexander Stoletov. It was possible to fully describe the mechanism of the photoelectric effect even later - humanity owes this to Albert Einstein. By the way, it was for this work that he received the Nobel Prize.

Baccarelle, Stoletov and Einstein are the scientists who laid the foundation of modern solar energy

The creation of the first solar photocell based on crystalline silicon was announced to the world by employees of Bell Laboratories back in April 1954. This date, in fact, is the starting point of technology, which will soon be able to become a full-fledged replacement for hydrocarbon fuel.

Since the current of one photovoltaic cell is milliamps, to generate electricity of sufficient power they have to be connected in modular structures. Protected from external influence arrays of solar photocells are a solar battery (due to its flat shape, the device is often called a solar panel).

Converting solar radiation into electricity has enormous prospects, because for every square meter of the earth's surface there is an average of 4.2 kW/hour of energy per day, which saves almost one barrel of oil per year. Initially used only for the space industry, the technology became so commonplace already in the 80s of the last century that photocells began to be used for domestic purposes - as a power source for calculators, cameras, lamps, etc. At the same time, “serious” solar-electric installations were created. Attached to the roofs of houses, they made it possible to completely abandon wired electricity. Today we can observe the birth of power plants, which are multi-kilometer fields of silicon panels. The power they generate can power entire cities, so we can say with confidence that the future lies with solar energy.

Modern solar power plants are multi-kilometer fields of photocells capable of supplying electricity to tens of thousands of homes.

Solar battery: how it works

After Einstein described the photoelectric effect, the whole simplicity of such a seemingly complex physical phenomenon was revealed to the world. It is based on a substance whose individual atoms are in an unstable state. When “bombarded” by photons of light, electrons are knocked out of their orbits - these are the sources of current.

For almost half a century the photoelectric effect did not have practical application for one simple reason - there was no technology for producing materials with an unstable atomic structure. Prospects for further research appeared only with the discovery of semiconductors. The atoms of these materials either have an excess of electrons (n-conductivity) or lack them (p-conductivity). When using a two-layer structure with an n-type (cathode) and a p-type (anode) layer, the bombardment of light photons knocks electrons out of the n-layer atoms. Leaving their places, they rush into the free orbits of the atoms of the p-layer and then, through the connected load, return to their original positions. Probably each of you knows that the movement of electrons in closed loop represents electricity. But it is possible to force electrons to move not thanks to a magnetic field, as in electric generators, but due to the flow of particles from solar radiation.

The solar panel works thanks to the photoelectric effect, which was discovered at the beginning of the 19th century.

Since the power of a single photovoltaic module is not sufficient to power electronic devices, a series connection of many cells is used to obtain the required voltage. As for the current strength, it is being increased parallel connection a certain number of such assemblies.

The generation of electricity in semiconductors directly depends on the amount solar energy, therefore, photocells are not only installed in the open air, but they also try to orient their surface perpendicular to the incident rays. And in order to protect the cells from mechanical damage and atmospheric influences, they are mounted on a rigid base and protected with glass on top.

Classification and features of modern photocells

The first solar cell was made based on selenium (Se), but the low efficiency (less than 1%), rapid aging and high chemical activity of selenium solar cells forced the search for other, cheaper and efficient materials. And they were found in the form of crystalline silicon (Si). Since this element of the periodic table is a dielectric, its conductivity was ensured by inclusions of various rare earth metals. Depending on the manufacturing technology, there are several types of silicon photocells:

• monocrystalline;
• polycrystalline;
• from amorphous Si.

The first ones are made by cutting off the thinnest layers from silicon ingots of the highest purity. Externally, monocrystalline photocells look like single-color dark blue glass plates with a pronounced electrode grid. Their efficiency reaches 19%, and their service life is up to 50 years. And although the performance of panels made on the basis of monocrystals is gradually falling, there is evidence that batteries manufactured more than 40 years ago remain operational today, delivering up to 80% of their original power.

Monocrystalline solar cells have a uniform dark color and cut corners - these signs do not allow them to be confused with other photocells

In the production of polycrystalline solar cells, less pure, but cheaper silicon is used. The simplification of technology affects the appearance of the plates - they do not have a uniform shade, but a lighter pattern, which is formed by the boundaries of many crystals. The efficiency of such solar cells is slightly lower than that of monocrystalline ones - no more than 15%, and the service life is up to 25 years. It must be said that the decrease in basic operational indicators had absolutely no effect on the popularity of polycrystalline solar cells. They benefit from a lower price and less dependence on external pollution, low clouds and orientation to the Sun.

Polycrystalline solar cells have a lighter blue tint and a heterogeneous pattern is a consequence of the fact that their structure consists of many crystals

For solar cells made from amorphous Si, it is not the crystalline structure that is used, but the thinnest layer silicon, which is sprayed onto glass or polymer. Although this production method is the cheapest, such panels have the shortest lifespan, which is caused by fading and degradation of the amorphous layer in the sun. This type of photocells is also not pleased with its performance - their efficiency is no more than 9% and during operation it decreases significantly. The use of solar panels made of amorphous silicon is justified in deserts - high solar activity offsets the drop in productivity, and the vast expanses allow the placement of solar power plants of any size.

The ability to sputter a silicon structure onto any surface makes it possible to create flexible solar panels

Further development of photovoltaic cell production technology is driven by the need to reduce prices and improve performance characteristics. Film photocells today have the highest performance and durability:

• based on cadmium telluride;
• from thin polymers;
• using indium and copper selenide.

It is too early to talk about the possibility of using thin-film photocells in homemade devices. Today, only a few of the most technologically “advanced” companies are engaged in their production, so most often flexible solar cells can be seen as part of finished solar panels.

What are the best photovoltaic cells for a solar cell and where can you find them?

Homemade solar panels will always be one step behind their factory-made counterparts, and there are several reasons for this. Firstly, famous manufacturers Photocells are carefully selected, eliminating cells with unstable or reduced parameters. Secondly, in the manufacture of solar electric batteries, special glass with increased light transmission and reduced reflectivity is used - it is almost impossible to find this on sale. And thirdly, before starting serial production, all parameters of industrial designs are tested using mathematical models. As a result, the effect of cell heating on the battery efficiency is minimized, the heat removal system is improved, the optimal cross-section of connecting busbars is found, ways to reduce the degradation rate of photocells are explored, etc. It is impossible to solve such problems without an equipped laboratory and appropriate qualifications.

The low cost of homemade solar panels makes it possible to build an installation that allows you to completely abandon the services of energy companies

Nevertheless, self-made solar panels show good performance results and are not so far behind their industrial counterparts. As for the price, here we have a gain of more than twice, that is, at the same cost, homemade products will provide twice as much electricity.

Taking into account all of the above, a picture emerges of which solar cells are suitable for our conditions. Film ones disappear due to lack of availability on sale, and amorphous ones - due to short term service and low efficiency. What remains are cells made of crystalline silicon. It must be said that in the first home-made device it is better to use cheaper “polycrystals”. And only after testing the technology and getting the hang of it, you should switch to monocrystalline cells.

Cheap, substandard photocells are suitable for testing technologies - just like high-quality devices, they can be bought abroad trading platforms

As for the question of where to get inexpensive solar cells, they can be found on foreign trading platforms such as Taobao, Ebay, Aliexpress, Amazon, etc. There they are sold both in the form of individual solar cells various sizes both productivity and ready-made sets for assembling solar panels of any power.

Sellers often offer so-called class “B” solar cells, which are damaged mono- or polycrystalline solar cells. Small chips, cracks or missing corners have virtually no effect on the performance of the cells, but allow you to purchase them at a much lower cost. It is for this reason that they are most profitable to use in homemade solar energy devices.

Is it possible to replace photovoltaic plates with something else?

Rarely does anyone home handyman there is no treasured box with old radio components. But diodes and transistors from old receivers and televisions are still the same semiconductors with p-n junctions, which, when illuminated, sunlight generate current. By taking advantage of these properties and connecting several semiconductor devices, you can make a real solar battery.

To manufacture a low-power solar battery, you can use the old element base of semiconductor devices

An attentive reader will immediately ask what the catch is. Why pay for factory-made mono- or polycrystalline cells when you can use what is literally under your feet. As always, the devil is in the details. The fact is that the most powerful germanium transistors allow you to obtain a voltage of no more than 0.2 V in bright sunlight at a current measured in microamps. In order to achieve the parameters that a flat silicon solar cell produces, you will need several dozen, or even hundreds of semiconductors. A battery made from old radio components is only suitable for charging a camping LED flashlight or a small battery mobile phone. To implement larger-scale projects, you cannot do without purchased solar cells.

How much power can you expect from solar panels?

When thinking about building your own solar power plant, everyone dreams of completely abandoning wired electricity. In order to analyze the reality of this idea, we will do some small calculations.

Finding out your daily electricity consumption is easy. To do this, just look at the invoice sent by the energy supply organization and divide the number of kilowatts indicated there by the number of days in the month. For example, if you are offered to pay for 330 kWh, this means that daily consumption is 330/30 = 11 kWh.

Graph of solar battery power depending on illumination

In your calculations, you should definitely take into account the fact that the solar panel will generate electricity only during daylight hours, with up to 70% of the generation occurring between 9 a.m. and 4 p.m. In addition, the efficiency of the device directly depends on the angle of incidence of sunlight and the state of the atmosphere.

Slight cloudiness or haze will reduce the efficiency of the solar installation's current output by 2–3 times, while a sky overcast by continuous clouds will cause a drop in performance by 15–20 times. Under ideal conditions, a solar battery with a capacity of 11/7 = 1.6 kW would be sufficient to generate 11 kWh of energy. Taking into account the influence of natural factors, this parameter should be increased by approximately 40–50%.

In addition, there is another factor that forces us to increase the area of ​​​​the photocells used. Firstly, we should not forget that the battery will not work at night, which means that powerful batteries will be needed. Secondly, to power household appliances you need a current of 220 V, so you will need a powerful voltage converter (inverter). Experts say that losses on the accumulation and transformation of electricity take up to 20–30% of its total amount. Therefore, the actual power of the solar battery should be increased by 60–80% of the calculated value. Taking an inefficiency value of 70%, we obtain the rated power of our solar panel equal to 1.6 + (1.6×0.7) = 2.7 kW.

The use of high-current assemblies lithium batteries is one of the most elegant, but by no means the cheapest way to store solar electricity

To store electricity, you will need low-voltage batteries designed for voltages of 12, 24 or 48 V. Their capacity must be designed for daily energy consumption plus transformation and conversion losses. In our case, we will need an array of batteries designed to store 11 + (11×0.3) = 14.3 kW×hour of energy. If you use regular 12-volt car batteries, you will need a 14300 Wh / 12 V = 1200 Ah assembly, that is, six batteries rated at 200 amp-hours each.

As you can see, even in order to provide electricity for the household needs of an average family, you will need a serious solar-electric installation. As for the use of homemade solar panels for heating, at this stage such an idea will not even reach the limits of self-sufficiency, not to mention the fact that something can be saved.

Battery size calculation

The size of the battery depends on the required power and the dimensions of the current sources. When choosing the latter, you will definitely pay attention to the variety of photocells offered. For use in homemade devices, it is most convenient to choose medium-sized solar cells. For example, polycrystalline panels measuring 3x6 inches are designed for an output voltage of 0.5 V and a current of up to 3 A.

When manufacturing a solar battery, they will be connected in series into blocks of 30 pieces, which will make it possible to obtain the voltage required for charging a car battery of 13–14 V (taking into account losses). The maximum power of one such unit is 15 V × 3 A = 45 W. Based on this value, it will not be difficult to calculate how many elements will be needed to build a solar panel of a given power and determine its dimensions. For example, to build a 180-watt solar electric collector, you will need 120 photocells with a total area of ​​2160 square meters. inches (1.4 sq.m).

Building a homemade solar panel

Before you start manufacturing a solar panel, you should solve the problems of its placement, calculate the dimensions and prepare the necessary materials and tools.

Choosing the right installation location is important

Since the solar panel will be made by hand, its aspect ratio can be any. This is very convenient, since a homemade device can be more successfully integrated into the exterior of the roof or the design of a suburban area. For the same reason, you should choose a place to install the battery before starting design activities, remembering to take into account several factors:

• openness of the place to sunlight during daylight hours;
• absence of shading buildings and tall trees;
• minimum distance to the room in which storage power and converters are installed.

Of course, a roof-mounted battery looks more organic, but placing the device on the ground has more advantages. In this case, the possibility of damage is eliminated roofing materials When installing a supporting frame, the complexity of installing the device is reduced and it becomes possible to timely change the “angle of attack of the sun’s rays.” And most importantly, with a lower placement it will be much easier to keep the surface of the solar panel clean. And this is a guarantee that the installation will work at full capacity.

Mounting a solar panel on a roof is driven more by space constraints than by necessity or ease of use.

What you will need during the work process

When starting to make a homemade solar panel, you should stock up on:

• photocells;
• stranded copper wire or special busbars for connecting solar cells;
• solder;
• Schottky diodes, designed for the current output of one photocell;
• high-quality anti-reflective glass or plexiglass;
• slats and plywood for making a frame;
• silicone sealant;
• hardware;
• paint and protective composition for processing wooden surfaces.

In the work you will need the simplest tool that a homely owner always has at hand - a soldering iron, glass cutter, saw, screwdriver, paint brush, etc.

Manufacturing instructions

To make the first solar battery, it is best to use photocells with already soldered leads - in this case, the risk of damage to the cells during assembly is reduced. However, if you are skilled with a soldering iron, you can save some money by purchasing solar cells with open contacts. To build the panel we looked at in the examples above, you will need 120 plates. Using an aspect ratio of approximately 1:1, 15 rows of photocells of 8 each will be required. In this case, we will be able to connect every two “columns” in series, and connect four such blocks in parallel. This way you can avoid tangled wires and get a smooth, beautiful installation.

Scheme electrical connections home solar power station

Frame

Assembling a solar panel should always begin with making the housing. For this we need aluminum corners or wooden slats no more than 25 mm high - in this case they will not cast a shadow on the outer rows of photocells. Based on the dimensions of our 3 x 6 inch (7.62 x 15.24 cm) silicon cells, the frame size should be at least 125 x 125 cm. If you decide to use a different aspect ratio (for example, 1:2), the frame can be further strengthened with a crossbar made of lath the same section.

The back side of the body should be covered with a panel made of plywood or OSB, and a drill should be drilled in the lower end of the frame ventilation holes. The connection between the internal cavity of the panel and the atmosphere will be needed to equalize the humidity - otherwise, fogging of the glass cannot be avoided.

To make a solar panel housing, the simplest materials are suitable - wooden slats and plywood.

By external size frame, a panel is cut out of plexiglass or high-quality glass with a high degree of transparency. In extreme cases, window glass up to 4 mm thick can be used. For its fastening, corner brackets are prepared, in which drillings are made for fastening to the frame. When using plexiglass, you can make holes directly in the transparent panel - this will simplify assembly.

To protect wooden case solar battery from moisture and fungus, it is impregnated with an antibacterial composition and painted with oil paint.

For ease of assembly of the electrical part, a substrate is cut out of fiberboard or other dielectric material according to the internal size of the frame. In the future, photocells will be installed on it.

Soldering plates

Before you start soldering, you should “figure out” the placement of photocells. In our case, we will need 4 cell arrays of 30 plates each, and they will be located in fifteen rows in the case. Such a long chain will be inconvenient to work with, and the risk of damage to fragile glass plates increases. It would be rational to connect 5 parts each, and complete the final assembly after the photocells are mounted on the substrate.

For convenience, photocells can be mounted on a non-conductive substrate made of textolite, plexiglass or fiberboard

After connecting each chain, you should check its functionality. To do this, each assembly is placed under table lamp. By recording current and voltage values, you can not only monitor the performance of the modules, but also compare their parameters.

For soldering we use a low-power soldering iron (maximum 40 W) and good, low-melting solder. We apply it in small quantities to the lead parts of the plates, after which, observing the polarity of the connection, we connect the parts to each other.

When soldering photocells, extreme care should be taken, since these parts are highly fragile.

Having collected the individual chains, we unfold them with their backs towards the substrate and using silicone sealant glue to the surface. Each 15-volt photocell unit is equipped with a Schottky diode. This device allows current to flow only in one direction, so it will not allow the batteries to discharge when the solar panel voltage is low.

The final connection of individual strings of photocells is carried out according to the above electrical diagram. For these purposes, you can use a special bus or stranded copper wire.

The hanging elements of the solar battery should be secured with hot-melt adhesive or self-tapping screws.

Panel assembly

The substrates with photocells located on them are placed in the housing and secured with self-tapping screws. If the frame is reinforced with a cross member, then several drillings are made in it for mounting wires. The cable that is brought out is securely fixed to the frame and soldered to the terminals of the assembly. To avoid confusion with polarity, it is best to use two-color wires, connecting the red terminal to the “plus” of the battery, and the blue one to its “minus”. A continuous layer of silicone sealant is applied along the upper contour of the frame, on top of which the glass is laid. After final fixation, the assembly of the solar battery is considered complete.

After the sealant has been installed protective glass, the panel can be transported to the installation site

Installation and connection of a solar battery to consumers

For a number of reasons, a homemade solar panel is a rather fragile device, and therefore requires a reliable supporting frame. Ideal option There will be a design that will allow the source of free electricity to be oriented in both planes, but the complexity of such a system is most often a strong argument in favor of a simple inclined system. It is a movable frame that can be set at any angle to the light. One of the options for a frame made of wooden beam, is presented below. You can use metal corners, pipes, tires, etc. to make it - whatever you have at hand.

Solar battery frame drawing

To connect the solar panel to the batteries, you will need a charge controller. This device will monitor the state of charge and discharge of batteries, monitor current output and switch to mains power in the event of a significant voltage drop. A device of the required power and required functionality can be purchased at the same retail outlets where photocells are sold. Regarding nutrition household consumers, then for this you will need to transform the low-voltage voltage into 220 V. Another device - an inverter - successfully copes with this. It must be said that the domestic industry produces reliable devices with good performance characteristics, so the converter can be purchased locally - in this case, a “real” guarantee will be a bonus.

One solar battery will not be enough to fully power your home - you will also need batteries, a charge controller and an inverter

On sale you can find inverters of the same power, differing in price several times. This scatter is explained by the “purity” of the output voltage, which is a necessary condition feeding individual electrical devices. Converters with the so-called pure sine wave have a more complicated design, and as a result, a higher cost.

Video: making a solar panel with your own hands

Building a home solar power plant is a non-trivial task and requires both financial and time costs, as well as minimal knowledge of basic electrical engineering. When starting to assemble a solar panel, you should observe maximum attention and accuracy - only in this case can you count on good decision question. Finally, I would like to remind you that glass contamination is one of the factors affecting productivity. Remember to clean the surface of the solar panel in a timely manner, otherwise it will not be able to work at full capacity.

are photovoltaic converters (solar modules) that convert the energy of sunlight into electricity. In order to use household appliances in a house using a solar battery, there must be quite a lot of such modules.

The energy generated by one module is not enough to meet the energy needs. Photoelectric converters are connected to each other by one series circuit.

Parts that make up a solar battery:

1. Solar modules,combined into frames. From units to several dozen photovoltaic elements are combined in one frame. To provide electricity to an entire house, you will need several panels with elements.
2. . Serves to accumulate the energy received, which can then be used in the dark.
3. Controller. It monitors the discharge and charging of the battery.
4. . Converts D.C., received from solar modules into variable.

Solar module (or photovoltaic cell) based on the principle p-n junction, and its structure is very similar to a transistor. If you cut off the cap of a transistor and direct the sun's rays onto the surface, then a tiny electric current can be determined with a device connected to it. The solar module works on the same principle, only the transition surface of the solar cell is much larger.

Like many types of transistors, solar cells are made from crystalline silicon.

Based on manufacturing technology and materials, three types of modules are distinguished:

1. Monocrystalline. Manufactured in the form of cylindrical silicon ingots. The advantages of the elements are high performance, compactness and longest service life.
2. Thin film. Layers of a photoelectric converter are sputtered onto a thin substrate. The efficiency of thin-film modules is relatively low (7-13%).
3. Polycrystalline. Molten silicon is poured into square shape, then the cooled material is cut into square plates. Externally they differ from monocrystalline modules in that the edges of the corners of polycrystalline plates are not cut off.

Battery. Lead-acid batteries are most commonly used in solar panels. A standard battery has a voltage of 12 volts; to obtain higher voltage, battery packs are assembled. This way you can assemble a unit with a voltage of 24 and 48 volts.

Solar charge controller. The charge controller operates on the principle of a voltage regulator in a car. Basically, 12 volts produce a voltage of 15 to 20 volts, and without a controller they can be damaged by overload. When the battery is 100% charged, the controller turns off the modules and protects the battery from boiling.

Inverter. Solar modules produce direct current, but to use household appliances and appliances, alternating current and a voltage of 220 volts are required. Inverters are designed to convert direct current into alternating current.

Selection of components for manufacturing

To reduce the cost of a solar station, you need to try to assemble it yourself. To do this, you will need to purchase the necessary components; some elements can be made yourself.

You can assemble it yourself:

• frames with photoelectric converters;
• charging controller;
• voltage inverter;

The biggest costs will be associated with purchasing the solar cells. Parts can be ordered from China or on eBay, this option will be cheaper.

It is prudent to purchase functional converters with damage and defects - they are simply rejected by the manufacturer, but are quite serviceable. Items cannot be purchased different sizes and power - the maximum current of the solar battery will be limited by the current of the smallest element.

To make a frame with solar cells you will need:

• aluminum profile;
• solar cells (usually 36 pieces for one frame);
• solder and flux;
• drill;
• made fastenings;
• silicone sealant;
• copper busbar;
• a sheet of transparent material (plexiglass, polycarbonate, plexiglass);
• sheet of plywood or textolite (plexiglass);
• Schottky diodes;

Assembling the inverter yourself makes sense only if the power consumption is low. A simple charge controller is not that expensive, so there is little point in wasting time on making the device.

DIY manufacturing technology

To assemble solar panels you will need:

1. Design a frame (case).
2. Solder all solar cells in a parallel circuit.
3. Attach solar cells to the frame.
4. Make the case airtight - direct hit atmospheric precipitation on photovoltaic cells is unacceptable.
5. Place the battery in the area of ​​greatest sunlight.

To meet the energy needs of a private home, one solar panel (frame) will not be enough. Based on practice, from one square meter The solar panel can produce 120 watts of power. For normal energy supply to a residential building, you will need about 20 square meters. m. area of ​​solar cells.

Most often, the batteries are placed on the roof of the house on the sunny side.

Housing assembly

The body can be assembled from plywood sheets and slats, or from aluminum corners and sheets and plexiglass (textolite). You need to decide how many elements will be placed in the frame. It should be taken into account that a gap of 3-5 mm is required between the elements, and the size of the frame is calculated taking into account these distances. The distance is necessary so that during thermal expansion the plates do not touch each other.

Assembling a structure from aluminum profile and plexiglass:

• a rectangular frame is made from an aluminum corner;
• Holes for fastening are drilled in the corners of the aluminum body;
• on inner part silicone sealant is applied around the entire perimeter of the housing profile;
• a sheet of plexiglass (textolite) is installed in the frame and pressed tightly against the frame;
• Mounting corners are placed in the corners of the case using screws, which securely fix the sheet of transparent material in the case;
• the sealant is allowed to dry thoroughly;

That's it, the body is ready. Before placing solar cells in the housing, you must thoroughly wipe the surface from dirt and dust.

Connection of photocells

When handling photoelectronic elements, you should remember that they are very fragile and require careful handling. Before connecting the plates in a serial chain, they are first carefully but gently wiped - the plates must be perfectly clean.

If the photocells were purchased with soldered conductors, this simplifies the process of connecting the modules. But before assembly, in this case, it is necessary to check the quality of the finished soldering, and if there are any irregularities, eliminate them.

Photovoltaic plates have contacts on both sides - these are contacts of different polarities. If the conductors (buses) have not yet been soldered, you must first solder them to the contacts of the plates, and then connect the photovoltaic elements to each other.

To solder busbars to photovoltaic modules, you need:

1. Measure the required length of the tire and cut into pieces required quantity stripes.
2. Wipe the contacts of the plates with alcohol.
3. Apply a thin layer of flux to the contact along the entire length of the contact on one side.
4. Place the busbar exactly along the length of the contact and slowly move the heated soldering iron over the entire soldering surface.
5. Turn the plate over and repeat all soldering operations on the other side.

Do not press the soldering iron too hard against the plate; the element may burst. It is also necessary to check the quality of soldering - there should be no irregularities on the front side of the photocells. If the bumps and roughness remain, you need to carefully go over the contact seam with a soldering iron again. You must use a low-power soldering iron.

What needs to be done to correctly and accurately connect photovoltaic cells:

1. If you have no experience in assembling elements, it is recommended to use a marking surface on which to place the elements (plywood sheet).
2. Position the solar panels strictly according to the markings. When marking, do not forget to leave a distance between elements of 5 mm.
3. When soldering the contacts of the plates, be sure to monitor the polarity. The photocells must be correctly assembled in a series circuit, otherwise the battery will not work properly.

Mechanical installation of panels:

1. Make markings for the plates in the body.
2. Place the solar cells in the housing, placing them on plexiglass. Secure it in the frame with silicone glue at the marked places. Do not apply a lot of glue, just a tiny drop in the center of the plate. Press carefully so as not to damage the plates. It is better to move the plates into the housing together; it will be inconvenient for one person.
3. Connect all the wires along the edges of the plates to common busbars.

Before sealing the panel, you need to test the quality of the soldering. The structure is carefully brought closer to sunlight and the voltage on the common buses is measured. It should be within expected values.

Alternatively, sealing can be done as follows:

1. Apply beads of silicone sealant between the plates and along the edges of the body, carefully press the edges of the photocells against the plexiglass with your fingers. It is necessary that the elements fit as tightly as possible to the transparent base.
2. Place a small weight on all edges of the elements, for example, heads from a car tool kit.
3. Allow the sealant to dry thoroughly, the plates will be securely fixed during this time.
4. Then carefully coat all the joints between the plates and the edges of the frame. That is, you need to lubricate everything in the body except the plates themselves. It is permissible for sealant to get on the edges of the back side of the plates.

Final assembly of the solar battery

1. Install a connector on the side of the housing, Connect the connector to Schottky.
2. Close with outside plates with protective screen made of transparent material. IN in this case, plexiglass. The structure must be sealed and prevent moisture from penetrating into it.
3. It is advisable to treat the front side (plexiglass), for example, varnish (varnish PLASTIK-71).

What is a Schottky diode used for? If the light falls on only part of the solar battery, and the other part is darkened, the cells may fail.

Diodes help avoid structural failure in such cases. In this case, power is lost by 25%, but you can’t do without diodes - they shunt the current, the current bypasses the photocells. To keep the voltage drop to a minimum, it is necessary to use low-resistance semiconductors, such as Schottky diodes.

Advantages and disadvantages of a solar battery

Solar panels have both advantages and disadvantages. If there were only one advantage from the use of photoelectric converters, the whole world would have switched to this type of electricity generation long ago.

Advantages:

1. Autonomy of the power supply, there is no dependence on voltage interruptions in the centralized power grid.
2. No subscription fee for the use of electricity.

Flaws:

1. High cost equipment and elements.
2. Dependence on sunlight.
3. Possibility of element damage solar battery due to adverse weather conditions (hail, storm, hurricane).

In what cases is it advisable to use a photovoltaic cell installation:

1. If the object (house or cottage) is located at a great distance from the power line. It could be country cottage in the rural outback.
2. When the property is located in a southern sunny area.
3. When combined various types energy. For example, heating a private house using stove heating and solar energy. The cost of a low-power solar station will not be so high, and can be economically justified in this case.

Installation

The battery must be installed in a location with maximum sunlight exposure. The panels can be mounted on the roof of the house, on a rigid or rotating bracket.

The front of the solar panel should face south or southwest at an angle of 40 to 60 degrees. During installation, external factors must be taken into account. The panels should not be blocked by trees or other objects, and dirt should not get on them.

1. It is better to buy photocells with minor defects. They are also functional, just not as beautiful appearance. New elements are very expensive; assembling a solar battery will not be economically justified. If there is no particular rush, it is better to order the plates on eBay, it will cost even less. You need to be careful with shipping from China - there is a high probability of receiving defective parts.
2. Photocells need to be purchased with a small margin, there is a high probability of their breaking during installation, especially if there is no experience in assembling such structures.
3. If the elements are not yet used, you should hide them in a safe place to avoid breakage of fragile parts. Do not stack the plates in large piles - they may burst.
4. During the first assembly, you should make a template, on which the locations of the plates will be marked before assembly. This makes it easier to measure the distances between elements before soldering.
5. Soldering must be done with a low-power soldering iron., and under no circumstances apply force when soldering.
6. It is more convenient to use aluminum corners for assembling the case, wooden structure less reliable. It is better to use plexiglass or other similar material as a sheet on the back side of the elements; it is more reliable than painted plywood and looks aesthetically pleasing.
7. Photovoltaic panels should be located in places where solar lighting will be maximum throughout the daylight hours.

House power supply diagram

The sequential power supply circuit for a private solar-powered home is as follows:

1. Solar battery from several panels, which are located on the slope of the roof of the house, or on a bracket. Depending on energy consumption, there can be up to 20 panels or more. The battery produces a direct current of 12 volts.
2. Charge controller. The device protects batteries from premature discharge and also limits the voltage in the DC circuit. Thus, the controller protects the batteries from overload.
3. Voltage inverter. Converts direct current to alternating current, thereby allowing household appliances to consume electricity.
4. Batteries. For private houses and cottages, several batteries are installed, connecting them in series. Serve to store energy. Battery energy is used at night when the solar battery cells do not produce current.
5. Electricity meter.

Quite often in private homes, the power supply system is supplemented with a backup generator.

In general, assembling a solar battery with your own hands is not that difficult. All you need is certain tools, patience and accuracy.

Your own power supply will help out both in the absence of a centralized network (in remote and hard-to-reach regions, in the country, on a hike), and when building a more environmentally friendly approach to the consumption of natural resources.

It is not difficult to assemble your own solar station; it contains only four components:

• solar panels;
• battery charge;
• controller;
• inverter

All of them are easy to find and order through online stores. But how to make a solar power plant with your own hands in order to create a full-fledged autonomous power supply system at home? First, you need to collect information about your needs, the capabilities of the area where the solar station will operate, and make all the necessary calculations for selecting the components.

How to calculate the number of solar panels

Choosing a solar station begins with searching for information on insolation in your area - the amount of solar energy that hits the earth's surface (measured in watts per square meter). This data can be found in special weather reference books or on the Internet. Typically, insolation is indicated separately for each month, because the level is highly dependent on the season. If you plan to use a solar station all year round, then you need to focus on the months with the lowest indicators.

Next, you need to calculate your electricity needs for each month. Remember that for an autonomous power supply system, not only the efficiency of energy storage plays a role, but also its economical use. Smaller needs will allow you to save significantly when purchasing solar panels and creating a budget version of a solar power station with your own hands.

Compare your electricity needs with the level of insolation in your area and you will find out the area of ​​solar panels that is needed for your solar station. Please note that the efficiency of the panels is only 12-14%. Always focus on the lowest figure.

Thus, if the insolation level in the most unfavorable month in your area is 20 kWh/m², then with an efficiency of 12% one panel with an area of ​​0.7 m² will produce 1.68 kWh. Your energy requirement, for example, is 80 kWh/month. This means that in the least sunny month, 48 panels (80/1.68) will be able to satisfy this need. You can read more about how to choose solar panels in our previous one.

How to install a solar panel

For best efficiency The solar panel must be installed so that the sun's rays fall on it at an angle of 90 degrees. Since the sun constantly moves across the sky, there are two solutions:

• Dynamic installation. Use a servo to make the solar panel rotate as the sun moves across the sky. The servo drive will allow you to collect 50% more energy than a static installation.
• Stationary installation. To get the most out of the fixed position of the solar panel, you need to find the installation angle at which the panel will collect the maximum possible amount of sun rays. For year-round operation, this angle is calculated using the formula +15 degrees to the latitude of the area. For the summer months this is -15 degrees to the latitude of the area.

How to choose a charge controller

Another way to assemble a solar power plant yourself to make it work efficiently is to use it, which allows you to track maximum power points (MPPT). Such a controller can store energy even during low light conditions and continues to supply it to the battery in an optimal manner.

So, energy from solar panels goes to the battery. This allows energy to be stored so that it can be used even in the absence of sunlight. In addition, batteries smooth out uneven energy supply, for example, during strong winds or clouds.

To correctly select and install a battery for a home solar power station with your own hands, you need to consider two parameters:

• It is very important that the charging current (from the panels) does not exceed 10% of the rated capacity level for acid batteries and 30% for alkaline devices.
• Low side voltage inverter design.

Consider battery self-discharge rates (not always indicated by manufacturers). For example, acid devices are recharged every six months to avoid breakdown.

How to choose an inverter

Description of parameters and mandatory functions of an ideal inverter:

• sinusoidal signal with distortion not exceeding three percent;
• when a load is connected, the voltage amplitude changes by no more than ten percent;
• double current conversion - direct and alternating;
• analog conversion part alternating current with a good transformer;
• short circuit protection;
• overload reserve.

When modeling your home's electrical system, group the loads so that different types of loads are powered by different inverters.

Solar power plants are a working alternative way to supply energy to a home. But not in all regions the insolation is sufficient to pay for solar equipment and to fully provide electricity. Sometimes it is worth paying attention to hybrid solar power plants, which can also be built with your own hands, but where, in addition to solar panels, there may be wind turbines, as well as diesel or even gasoline generators.

If you just want to try to “tame” solar energy, but are not ready to completely change the power supply to your home, make a mini solar power station with your own hands. It will consist of several solar panels, a battery and a controller. This will all fit in a suitcase, but will provide you with energy during a sudden power outage, a trip to the country or to nature. Calculations and selection of components follow the same principle as for a full-fledged home station.