Solar panels yourself. DIY solar panels. copper foil

Before creating it, the author read a lot about the use of renewable alternative energy, and most of all he was attracted to the use of solar energy using solar panels, since the method is the simplest and the panels do not require special maintenance during operation. The only negative was that the price of factory-made models of solar panels is very high. Therefore, the author decided to make them himself.

Let's consider the main stages of modeling and creating solar panels.

The author ordered the basic elements for creating solar panels through eBay. The main set of elements cost about $100, and the epoxy resin, which was already ordered from a St. Petersburg company, cost 1,300 rubles per kilogram. The glass on which everything was attached cost 350 rubles each.

The author’s main goal was to create high-quality solar panels at home that would look normal and last a very long time. It is for this reason that the author did not skimp on optical epoxy resin and on the elements themselves.

This is what a set of all the basic elements for assembling a solar panel looked like. The basic set also included tires and a pencil with flux, which will be needed in the process of soldering the elements:

And here is a photo of that very special optical super-transparent epoxy resin:

To test the transparent epoxy resin, as well as the speed of its hardening, the author first used it on just one element. The picture below shows the result of this action.

As a result, the transparency turned out to be perfect and the price of the epoxy resin was completely justified.

Inspired by such a high-quality result, the author continued assembling all the elements into a solar panel.
But before soldering the main elements, it was decided to make a base on which these elements would be attached, so that during the soldering process it would be possible to focus on certain dimensions of the future panel.

An aluminum frame was made from angle iron. After which the author applied a layer of silicone sealant and installed the glass. The result was a sealed frame for the photocells of the future solar panel.

While the frame was drying, the author began soldering the elements.

250 grams of epoxy resin was prepared, which the author applied to the glass in an even layer over the entire surface. Already in this resin I installed all 36 elements in row order, and then soldered them together.

At this stage, the first problem arose, which the author did not notice immediately. The elements themselves turned out to be not completely flat, but slightly curved at the edges, so in order to securely attach them to the glass with resin, you had to carefully press them with heavy objects and wait until they stick; this process took quite a lot of effort, since the elements for the solar panel themselves are very fragile . It is for this reason that the author decided to solder the elements directly inside the frame, and not in advance. After all, when transferring an already welded structure of elements onto glass, the risk of damaging the soldered elements increases many times over. In addition, fixing the elements to the glass before soldering provides a number of advantages regarding the aesthetic appearance of the panel itself. Thanks to this approach, there were no air bubbles left under the elements and the entire structure ended up looking monolithic.

Here is a photo of the panels already assembled:

He then began testing the solar panel. To do this, he placed it with photocells facing sunlight and measured the short circuit current, the strength of which was 3.6 A. It was this figure that was stated in the characteristics of the elements, and therefore the panel was assembled correctly and is fully functioning.

Below is a photo of the back of the solar panel. As you can see, all elements are protected from natural environmental phenomena (rain, snow, wind, dirt), which guarantees their long service life.

The panels can even withstand hail like this:

Recently, solar energy has become increasingly popular.
We decided to try to make a solar battery with our own hands.
There is not much information on the Internet. Most often, the same text is reprinted from one site to another.
Build Purpose solar collector with your own hands - evaluate the possibility of such an assembly and the economic sense.
So, a set of polycrystalline solar cells measuring 6*6 inches for a solar collector was ordered from China. The kit included 40 solar cells, a soldering pencil, and a connecting tape for soldering the elements. To reduce the cost, solar cells of class B were purchased, i.e. with defects. Defective wafers cannot be used for industrial production of solar panels, but are quite functional. Our goal is to reduce the budget.
Parameters declared by the seller: power of one element measuring 6*6 inches 4W, voltage 0.5V.
In order to be able to charge a 12V battery, it is necessary to assemble a panel with a voltage of 18V, i.e. you will need 36 elements. 4 spare elements.
After receiving a set of 40 solar cells, they were studied. The quality of the elements leaves much to be desired. Almost all of them have quite serious defects. Okay, our goal is to evaluate the possibility of assembling a solar panel with your own hands.
The purchased elements do not have soldered conductors, so you will have to solder them yourself.
As it turns out, it's not difficult at all. After soldering several elements, a certain technology was developed. Using a 25W soldering iron, a soldering pencil and available tin. The main thing is not to apply a lot of tin to the soldering area, then soldering is easy and it is done quite quickly. Checking the connection resulted in a split solar cell, i.e. the soldering is quite reliable.
After treating the soldering areas with a pencil, apply tin to these areas.
After soldering, a fairly cultural product is obtained.
So we solder all 40 elements.
We work carefully with a soldering iron. To work, you must choose a flat surface. It is most convenient to solder on a glass surface.
The first soldered element was tested on the street. Without load it produces 0.55V. This gives hope about the reality of getting 18V from 36 elements soldered in series.
Our goal was not the final product, so we decided not to make a housing for the solar panel, but to limit ourselves to a flat surface for a set of solar cells. We begin soldering the elements together.
Soldering, as already mentioned, is not difficult. But the elements are so fragile that they require very careful handling. After connecting 12 elements together in series, several pieces split. The uneven color of solar cells is the quality of the original cells.
They, of course, remained operational, but you can no longer expect the declared power from them.
We measure current without load directly in the room. Of course, these numbers won’t tell you anything, but we were interested.
12 solar cells produced about 4V.
We take our solar panel outside. There is a clear sky and active sun outside.
The panel produces a no-load voltage of about 7V. That is, we received the expected voltage.
Some results.
Some tips for this type of work. The conductor for connecting solar cells must be made strictly to size, taking into account the total length of one solar cell, the distance between the elements and the length of the conductor on the inside of the solar cell. The fact is that on the back of the solar cell it is necessary to use a conductor shorter than the cell itself. Precise adjustment of the conductor will allow you to quickly and accurately solder the elements. Cutting an already soldered conductor risks breaking the element.
Do not apply too much tin to the soldering area. It does not heat up well, which leads to stronger pressure with the soldering iron. There is a risk of the solar cell breaking.
To assemble a solar battery with your own hands, you first need to prepare a housing for the future solar battery. Then solar cells with soldered conductors are inserted and secured into it, and only then the solar cells are soldered together. This will avoid damage when transferring soldered elements.
Now a few words about the economy. The kit purchased on Ebay cost about 3,000 rubles. Solar cells of class A, i.e. without defects, are more expensive. Provided that we would have enough 40 obtained solar cells for a solar battery of 36 of these solar cells, and their power would correspond to the declared 4W, then we would get a panel with a voltage of 18V and a power of 144W. Additionally, you will have to make the solar battery housing with your own hands, spending some money.
We look on the Internet and easily find factory-made solar panels with similar characteristics for 6,000 rubles.
Do you need to make a solar battery yourself? In our opinion, no. A factory-produced solar panel will win in all respects: reliability, durability, technical parameters and price.

Content:

Providing comfortable living conditions in modern apartments and private homes cannot do without electrical energy, the need for which is constantly increasing. However, prices for this energy carrier are increasing with sufficient regularity. Accordingly, the overall costs of maintaining housing increase. Therefore, a do-it-yourself solar battery for a private home, along with other alternative sources of electricity, is becoming increasingly relevant. This method makes it possible to make an object energy independent in conditions of constant rising prices and power outages.

Efficiency of solar panels

The problem of autonomous power supply to devices and equipment in private homes has been considered for a long time. One of the alternative power options is solar energy, which in modern conditions has found wide application in practice. The only factor that raises doubts and controversy is the effectiveness solar panels, which does not always live up to expectations.

The performance of solar panels directly depends on the amount of solar energy. Thus, batteries will be most effective in regions where sunny days prevail. Even in ideal Battery efficiency is only 40%, and in real conditions this figure is much lower. Another condition for normal operation is the availability of significant areas for the installation of autonomous solar systems. If for country house This is not a serious problem, but apartment owners have to solve many additional technical problems.

Design and principle of operation

The operation of solar panels is based on the ability of photocells to convert solar energy into electrical energy. All together they are collected in the form of a multi-cell field, united into a common system. The action of solar energy turns each cell into a source of electric current, which is collected and stored in batteries. The dimensions of the total area of such a field directly affect the power of the entire device. That is, with an increase in the number of photocells, the amount of generated electricity also increases accordingly.

This does not mean that the required amount of electricity can only be generated over very large areas. There are many small household appliances that use solar energy - calculators, flashlights and other devices.

In modern country houses Solar-powered lighting devices are becoming increasingly popular. These simple and economical devices illuminate garden paths, terraces and other necessary places. At night, the electricity stored during the day when the sun is shining is used. The use of energy-saving lamps allows you to consume accumulated electricity over a long period of time. The solution to the main problems of energy supply is carried out with the help of other, more powerful systems allowing to generate a sufficient amount of electricity.

Main types of solar panels

Before you start making solar panels yourself, it is recommended that you familiarize yourself with their main types in order to choose the most suitable option for yourself.

All solar energy converters are divided into film and silicon, in accordance with their structure and design features. The first option is represented by thin-film batteries, where the converters are made in the form of a film made using a special technology. These structures are also known as polymer structures. They can be installed in any available location, however, they require a lot of space and have low efficiency. Even average cloudiness can reduce the efficiency of film devices by 20%.

Silicon batteries come in three types:

. The design consists of numerous cells with built-in silicon converters. They are joined together and filled with silicone. They are easy to use, lightweight, flexible, and waterproof. But to ensure effective operation of such batteries, exposure to direct sunlight is required. Despite the relatively high efficiency - up to 22%, when cloudiness occurs, electricity generation can significantly decrease or stop completely.
. Compared to monocrystalline ones, they have more converters housed in cells. Their installation was carried out in different directions, which significantly increases operating efficiency even in low light. These batteries are most widespread, especially in urban environments.
Amorphous. They have low efficiency - only 6%. However, they are considered very promising due to their ability to absorb light flux many times greater than that of the first two types.

All types of solar panels considered are manufactured in factories, so their price remains very high. In this regard, you can try to make a solar battery yourself, using inexpensive materials.

Selection of materials and parts for the manufacture of a solar battery

Since the high cost of autonomous solar energy sources makes them inaccessible for widespread use, home craftsmen can try to organize the manufacture of solar panels with their own hands from scrap materials. It should be remembered that when making a battery it is impossible to make do with only available materials. You will definitely have to buy factory parts, even if they are not new.

A solar energy converter consists of several basic elements. First of all, this is the battery itself of a certain type, which has already been discussed above. Next comes the battery controller, which controls the charge level of the batteries with the resulting electrical current. The next element is batteries that store electricity. It will be necessary to convert direct current into alternating current. Thus, all household appliances designed for 220 volts will be able to operate normally.

Each of these elements can be freely purchased on the electronics market. If you have certain theoretical knowledge and practical skills, then most of them can be assembled independently using standard circuits, including the solar battery controller. In order to calculate the power of the converter, you need to know for what purpose it will be used. This can be only lighting or heating, as well as fully meeting the needs of the facility. In this regard, materials and components will be selected.

When making a solar battery with your own hands, you need to determine not only the power, but also the operating voltage of the network. The fact is that solar powered networks can operate on direct or alternating current. The latter option is considered more preferable, since it allows the distribution of electricity to consumers over a distance of over 15 meters. When using polycrystalline batteries, from one square meter you can get, on average, about 120 W in one hour. That is, to obtain 300 kW per month, solar panels with a total area of 20 m2 will be required. This is exactly how much an ordinary family of 3-4 people spends.

In private homes and cottages, solar panels are used, each of which includes 36 elements. The power of one panel is about 65 W. In a small private house or country house, 15 panels capable of generating electrical power of up to 5 kW per hour are sufficient. After performing preliminary calculations, you can purchase conversion plates. It is acceptable to purchase damaged items with minor defects that only affect appearance batteries. In operating condition, each element is capable of delivering about 19 V.

Manufacturing of solar panels

After all materials and parts are prepared, you can begin assembling the converters. When soldering elements, it is necessary to provide a gap for expansion between them within 5 mm. Soldering should be done very carefully and carefully. For example, if the records have no wiring, they will need to be soldered manually. To work, you will need a 60-watt soldering iron, to which a regular 100-watt incandescent lamp is connected in series.

All plates are soldered in series to each other. The plates are characterized by increased fragility, so it is recommended to solder them using a frame. During desoldering, diodes are inserted into the circuit together with the photographic plates, protecting the photocells from discharge when the light level decreases or complete darkness sets in. For this purpose, the halves of the panel are combined in a common bus, which in turn is output to the terminal block, due to which a midpoint is created. The same diodes protect batteries from discharge at night.

One of the main conditions for efficient battery operation is high-quality soldering of all points and components. Before installing the substrate, these places must be tested. To output current, it is recommended to use conductors with a small cross-section, for example, a speaker cable in silicone insulation. All wires are secured with sealant. After this, the material for the surface to which the plates will be attached is selected. The most suitable characteristics are those of glass, which transmit light much better than carbonate or plexiglass.

When making a solar battery from improvised materials, you need to take care of the box. Typically the box is made from wooden beam or an aluminum corner, after which glass is placed in it on the sealant. The sealant should fill any imperfections and then dry completely. Due to this, dust will not get inside, and the photographic plates will not become dirty during operation.

Next, a sheet with soldered photocells is installed on the glass. It can be fixed in different ways, however, the most optimal options are considered clear epoxy resin or sealant. The entire surface of the glass is evenly coated with epoxy resin, then the transducers are installed on it. When using sealant, fastening is carried out at points in the center of each element. At the end of the assembly, you should get a sealed case, inside of which the solar battery is placed. The finished device will produce approximately 18-19 volts, which is quite enough to charge a 12 volt battery.

Possibility of home heating

After a homemade solar battery is assembled, every owner will probably want to test it in action. The most important problem is heating the house, so the first thing to check is the possibility of heating using solar energy.

Solar collectors are used for heating. With the help of a vacuum collector, sunlight is converted into heat. Thin glass tubes are filled with liquid, which is heated by the sun and transfers heat to water placed in a storage tank. In our case, this method is not suitable, since we are talking exclusively about converting solar energy into electrical energy.

It all depends on the power of the device used. In any case, heating the water in the boiler will consume most of the energy received. If 100 liters of water are heated to 70-80 degrees, it will take about 4 hours. The electricity consumption of a water boiler with 2 kW heating elements will be 8 kW. When generating electricity 5 kW per hour, there will be no problems. However, when the battery area is less than 10 m2, heating a private house with their help becomes impossible.

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:

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.
. Serves to accumulate the received energy, which can then be used in the dark.
Controller. It monitors the discharge and charging of the battery.
. Converts direct current received from solar modules into alternating current.

Solar module (or photovoltaic cell) based on p-n principle transition, 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:

Monocrystalline. Manufactured in the form of cylindrical silicon ingots. The advantages of the elements are high performance, compactness and longest service life.
Thin film. Layers of a photoelectric converter are sputtered onto a thin substrate. The efficiency of thin-film modules is relatively low (7-13%).
Polycrystalline. Molten silicon is poured into a square mold, then the cooled material is cut into square wafers. 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 the purchase of the solar cells themselves. 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. You cannot buy elements of 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 bus;
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:

Design a frame (case).
Solder all solar cells in a parallel circuit.
Attach solar cells to the frame.
Make the housing hermetically sealed - direct exposure of photovoltaic cells to atmospheric precipitation is unacceptable.
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, you can get 120 W of power from one square meter of solar panel. 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;
silicone sealant is applied to the inside of the housing profile along the entire perimeter;
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:

Measure the required length of the tire and cut the required number of strips into pieces.
Wipe the contacts of the plates with alcohol.
Apply a thin layer of flux to the contact along the entire length of the contact on one side.
Place the busbar exactly along the length of the contact and slowly move the heated soldering iron over the entire soldering surface.
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:

If you have no experience in assembling elements, it is recommended to use a marking surface on which to place the elements (plywood sheet).
Position the solar panels strictly according to the markings. When marking, do not forget to leave a distance between elements of 5 mm.
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:

Make markings for the plates in the body.
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.
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:

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.
Place a small weight on all edges of the elements, for example, heads from a car tool kit.
Allow the sealant to dry thoroughly, the plates will be securely fixed during this time.
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

Install a connector on the side of the housing, Connect the connector to Schottky.
Cover the outside of the plate with a protective screen made of transparent material. In this case, plexiglass. The structure must be sealed and prevent moisture from penetrating into it.
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:

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

Flaws:

High cost equipment and elements.
Dependence on sunlight.
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:

If the object (house or cottage) is located at a great distance from the power line. It could be a country cottage in the countryside.
When the property is located in a southern sunny area.
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 illumination. sunlight. 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.

It is better to buy photocells with minor defects. They are also functional, just not as beautiful in 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.
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.
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 stacks - they may burst.
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.
Soldering must be done with a low-power soldering iron., and under no circumstances apply force when soldering.
It is more convenient to use for assembling the case aluminum corners , 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.
Photovoltaic panels should be located in places where sunlight 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:

Multi-panel solar battery, 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.
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.
Voltage inverter. Converts direct current to alternating current, thereby allowing household appliances to consume electricity.
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.
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. You only need certain means, patience and accuracy.

For decades now, humanity has been searching for alternative energy sources that can at least partially replace existing ones. And the most promising of all today seem to be two: wind and solar energy.

True, neither one nor the other can provide continuous production. This is due to the variability of the wind rose and daily-weather-seasonal fluctuations in the intensity of the solar flux.

Today's energy industry offers three main methods of generating electrical energy, but all of them are harmful to the environment in one way or another:

Fuel electric power industry- the most environmentally polluting, accompanied by significant emissions of carbon dioxide, soot and useless heat into the atmosphere, causing a reduction in the ozone layer. The extraction of fuel resources for it also causes significant harm to the environment.
Hydropower is associated with very significant landscape changes, flooding of useful lands, and causes damage to fisheries resources.
Nuclear power- the most environmentally friendly of the three, but requires very significant costs to maintain safety. Any accident may be associated with causing irreparable, long-term harm to nature. In addition, it requires special measures for the disposal of used fuel waste.

Strictly speaking, there are several ways to obtain electricity from solar radiation, but most of them use its intermediate conversion into mechanical power, rotating the generator shaft, and only then into electrical power.

Such power plants exist, they use Stirling external combustion engines, they have good efficiency, but they also have a significant drawback: in order to collect as much solar radiation energy as possible, it is necessary to manufacture huge parabolic mirrors with systems for tracking the position of the sun.

It must be said that there are solutions to improve the situation, but they are all quite expensive.

There are methods that make it possible to directly convert light energy into electric current. And although the phenomenon of the photoelectric effect in the semiconductor selenium was discovered already in 1876, it was only in 1953, with the invention of the silicon photocell, that the real possibility of creating solar cells for generating electricity arose.

At this time, a theory was already emerging that made it possible to explain the properties of semiconductors and create a practical technology for their industrial production. To date, this has resulted in a real semiconductor revolution.

The operation of a solar battery is based on the phenomenon of semiconductor photoelectric effect. p-n junction, which is essentially a regular silicon diode. When illuminated, a photovoltage of 0.5~0.55 V appears at its terminals.

When using electric generators and batteries, it is necessary to take into account the differences that exist between. By connecting a three-phase electric motor to the appropriate network, you can triple its output power.

By following certain recommendations, with minimal costs in terms of resources and time, you can manufacture the power part of a high-frequency pulse converter for domestic needs. You can study the structural and circuit diagrams of such power supplies.

Structurally, each solar battery element is made in the form of a silicon wafer with an area of several cm2, on which many such photodiodes connected into a single circuit are formed. Each such plate is a separate module that produces a certain voltage and current when exposed to sunlight.

By connecting such modules into a battery and combining their parallel-serial connection, you can obtain a wide range of output power values.

The main disadvantages of solar panels:

Great unevenness and irregularity of energy output depending on the weather and the seasonal height of the sun.
Limits the power of the entire battery if at least one part of it is shaded.
Dependence on the direction of the sun at different times of the day. To use the battery as efficiently as possible, you need to ensure that it is always aimed at the sun.
In connection with the above, the need for energy storage. The greatest energy consumption occurs at a time when its production is minimal.
Large area required for a structure of sufficient power.
The fragility of the battery design, the need to constantly clean its surface from dirt, snow, etc.
Solar modules operate most efficiently at 25°C. During operation, they are heated by the sun to a much higher temperature, which greatly reduces their efficiency. To maintain optimal efficiency, the battery must be kept cool.

It should be noted that developments of solar cells using the latest materials and technologies are constantly appearing. This allows you to gradually eliminate the disadvantages inherent in solar panels or reduce their impact. Thus, the efficiency of the newest cells using organic and polymer modules has already reached 35% and there are expectations of reaching 90%, and this makes it possible to obtain much more power with the same battery dimensions, or, while maintaining energy efficiency, to significantly reduce the dimensions of the battery.

By the way, the average efficiency of a car engine does not exceed 35%, which suggests that solar panels are quite effective.

There are developments of elements based on nanotechnology that work equally effectively under different angles incident light, which eliminates the need for their positioning.

Thus, today we can talk about the advantages of solar panels compared to other energy sources:

No mechanical energy conversions or moving parts.
Minimal operating costs.
Durability 30~50 years.
Quiet operation, no harmful emissions. Environmentally friendly.
Mobility. The battery for powering a laptop and charging the battery for an LED flashlight will fit in a small backpack.
Independence from the presence of constant current sources. The ability to recharge the batteries of modern gadgets in the field.
Undemanding to external factors. Solar cells can be placed anywhere, on any landscape, as long as they receive enough sunlight.

In the equatorial regions of the Earth, the average solar energy flux is on average 1.9 kW/m2. In central Russia it is in the range of 0.7~1.0 kW/m2. The efficiency of a classic silicon photocell does not exceed 13%.

As experimental data show, if a rectangular plate is directed with its plane to the south, to the point of solar maximum, then over a 12-hour sunny day it will receive no more than 42% of the total luminous flux due to a change in its angle of incidence.

This means that with an average solar flux of 1 kW/m2, 13% battery efficiency and its total efficiency of 42% can be obtained in 12 hours no more than 1000 x 12 x 0.13 x 0.42 = 622.2 Wh, or 0 .6 kWh per day from 1 m 2. This is assuming a full sunny day, in cloudy weather it is much less, and in the winter months this value must be divided by another 3.

Taking into account voltage conversion losses, an automation circuit that provides optimal charging current for batteries and protects them from overcharging, and other elements, the figure of 0.5 kWh/m 2 can be taken as a basis. With this energy, you can maintain a battery charge current of 3 A at a voltage of 13.8 V for 12 hours.

That is, to charge a completely discharged car battery with a capacity of 60 Ah, a solar panel of 2 m2 will be required, and for 50 Ah - approximately 1.5 m2.

In order to obtain such power, you can purchase ready-made panels produced in the electrical power range of 10~300 W. For example, one 100 W panel for a 12-hour daylight hours, taking into account the coefficient of 42%, will provide 0.5 kWh.

Such a Chinese-made panel made of monocrystalline silicon with very good characteristics now costs about 6,400 rubles on the market. Less effective in open sun, but having better performance in cloudy weather, polycrystalline - 5,000 rubles.

If you have certain skills in installing and soldering electronic equipment, you can try to assemble such a solar battery yourself. At the same time, you should not count on a very large gain in price; in addition, the finished panels are of factory quality, both the elements themselves and their assembly.

But the sale of such panels is not organized everywhere, and their transportation requires very strict conditions and will be quite expensive. In addition, with self-production, it becomes possible, starting small, to gradually add modules and increase the output power.

Selection of materials for creating a panel

Chinese online stores, as well as eBay, offer a wide selection of items for self-made solar batteries with any parameters.

Even in the recent past, home-made workers purchased plates that were rejected during production, had chips or other defects, but were significantly cheaper. They are quite efficient, but have a slightly reduced power output. Given the constant decline in prices, this is now hardly advisable. After all, losing on average 10% of power, we also lose in the effective panel area. And the appearance of the battery, consisting of plates with broken pieces, looks quite artisanal.

You can also purchase such modules in Russian online stores, for example, molotok.ru offers polycrystalline elements with operating parameters at a luminous flux of 1.0 kW/m2:

Voltage: idling - 0.55 V, operating - 0.5 V.
Current: short circuit - 1.5 A, working - 1.2 A.
Operating power - 0.62 W.
Dimensions - 52x77 mm.
Price 29 rub.

Advice: It is necessary to take into account that the elements are very fragile and some of them may be damaged during transportation, therefore, when ordering, you should provide some reserve for their quantity.

Making a solar battery for your home with your own hands

To make a solar panel, we need a suitable frame, which you can make yourself or pick up a ready-made one. The best material to use for it is duralumin; it is not subject to corrosion, is not afraid of dampness, and is durable. With appropriate processing and painting, both steel and even wood are suitable for protection from atmospheric precipitation.

Advice: You should not make the panel very large: it will be inconvenient to assemble the elements, install and maintain. In addition, small panels have low windage and can be more conveniently placed at the required angles.

We calculate components

Let's decide on the dimensions of our frame. To charge a 12-volt acid battery, an operating voltage of at least 13.8 V is required. Let’s take 15 V as a basis. To do this, we will have to connect 15 V / 0.5 V = 30 elements in series.

Tip: The output of the solar panel should be connected to the battery through a protective diode to prevent it from self-discharging through solar cells at night. So the output of our panel will be: 15 V – 0.7 V = 14.3 V.

To obtain a charging current of 3.6 A, we need to connect three such chains in parallel, or 30 x 3 = 90 elements. It will cost us 90 x 29 rubles. = 2610 rub.

Tip: Solar panel elements are connected in parallel and in series. It is necessary to maintain equality in the number of elements in each sequential chain.

With this current we can provide a standard charge mode for a completely discharged battery with a capacity of 3.6 x 10 = 36 Ah.

In reality, this figure will be less due to uneven sunlight throughout the day. Thus, to charge a standard 60 Ah car battery, we will need to connect two such panels in parallel.

This panel can provide us with an electrical power of 90 x 0.62 W ≈ 56 W.

Or during a 12-hour sunny day, taking into account the correction factor of 42% 56 x 12 x 0.42 ≈ 0.28 kWh.

Let's place our elements in 6 rows of 15 pieces. To install all the elements we need a surface:

Length - 15 x 52 = 780 mm.
Width - 77 x 6 = 462 mm.

To freely accommodate all the plates, we will take the dimensions of our frame: 900×500 mm.

Tip: If there are ready-made frames with other dimensions, you can recalculate the number of elements in accordance with the outlines given above, select elements of other standard sizes, and try to place them by combining the length and width of the rows.

We will also need:

Electric soldering iron 40 W.
Solder, rosin.
Installation wire.
Silicone sealant.
Double sided tape.

Manufacturing stages

To install the panel, it is necessary to prepare a level workplace of sufficient area with convenient access from all sides. It is better to place the element plates themselves separately to the side, where they will be protected from accidental impacts and falls. You should take them carefully, one at a time.

Residual current devices improve the safety of your home electrical system by reducing the likelihood of electrical shock and fires. Detailed introduction to characteristic features different types Residual current switches will tell you for apartments and houses.

When using an electric meter, situations arise when it needs to be replaced and reconnected - you can read about this.

Typically, to produce a panel, they use the method of gluing plates of elements pre-soldered into a single circuit onto a flat base-substrate. We offer another option:

We insert it into the frame, fasten it well and seal the edges with glass or a piece of plexiglass.
We lay out the element plates on it in the appropriate order, gluing them with double-sided tape: the working side to the glass, the soldering leads to the back side of the frame.
By placing the frame on the table with the glass down, we can conveniently solder the terminals of the elements. We carry out electrical installation in accordance with the chosen circuit diagram inclusions.
We finally glue the plates on the back side with tape.
We put some kind of damping pad: sheet rubber, cardboard, fiberboard, etc.
We insert the back wall into the frame and seal it.

If desired, instead of the back wall, you can fill the frame at the back with some kind of compound, for example, epoxy. True, this will eliminate the possibility of disassembling and repairing the panel.

Of course, one 50 W battery is not enough to power even a small house. But with its help it is already possible to implement lighting in it using modern LED lamps.

For a comfortable existence of a city dweller, at least 4 kWh of electricity is now required per day. For a family - according to the number of its members.

Therefore, the solar panel of a private house for a family of three should provide 12 kWh. If the home is supposed to be supplied with electricity only from solar energy, we will need a solar battery with an area of at least 12 kWh / 0.6 kWh/m2 = 20 m2.

This energy must be stored in batteries with a capacity of 12 kWh / 12 V = 1000 Ah, or approximately 16 batteries of 60 Ah each.

For normal operation of a battery with a solar panel and its protection, a charge controller is required.

To convert 12 VDC to 220 VAC, you will need an inverter. Although now there is already a sufficient quantity of electrical equipment on the market for voltages of 12 or 24 V.

Tip: In low-voltage power supply networks, currents operate at significantly higher values, so when wiring to high-power equipment, you should select a wire of the appropriate cross-section. Wiring for networks with an inverter is carried out according to the usual 220 V circuit.

Drawing conclusions

Subject to the accumulation and rational use of energy, today non-traditional types of electric power are beginning to create a significant increase in the total volume of its production. One could even argue that they are gradually becoming traditional.

Considering the recently significantly reduced level of energy consumption of modern household appliances, the use of energy-saving lighting devices and the significantly increased efficiency of solar panels of new technologies, we can say that they are already capable of providing electricity for a small a private house in southern countries with a large number of sunny days a year.

In Russia, they may well be used as backup or additional energy sources in combined power supply systems, and if their efficiency can be increased to at least 70%, then it will be quite possible to use them as the main suppliers of electricity.