Solar cell technologies. DIY solar panel for home. Solar Panel Design

It all started with a walk through the eBay website - I saw solar panels and got sick.

Disputes with friends about payback were funny... When buying a car, no one thinks about the return on investment. A car is like a mistress, prepare the amount for pleasure in advance. And here it’s quite the opposite, you spent money and they are still trying to recoup... In addition, I connected an incubator to the solar panels so they still justify their purpose, protecting your future farm from destruction. In general, having an incubator, you depend on many factors, it’s either a master or a layman. When I have time, I’ll write about homemade incubator. Well, okay, why talk about it, everyone has the right to choose.....!

After much waiting, the treasured box with thin, fragile records finally warms my hands and heart.

First of all, of course, the Internet... well, it’s not the gods who burn the pots. Someone else's experience is always useful. And then disappointment set in... As it turned out, about five people made the panels with their own hands, the rest were simply copied onto their websites, some of them, in order to be more original, copied from different developments. Well, God bless them, let this remain on the conscience of the page owners.

I decided to read the forums; the long discussions of theorists on “how to milk a cow” led to complete despondency. Discussions about how plates break due to heat, the difficulties of sealing, etc. I read it and spat on the whole thing. We will go our own way, by trial and error, relying on the experience of “colleagues”; why reinvent the wheel?

Let's set the task:

1) The panel should be made from available materials so as not to stretch your wallet, since the result is unknown.

2) The manufacturing process should not be labor-intensive.

Let's start making a solar panel:

The first thing we purchased was 2 glasses 86x66 cm for the future two panels.

The glass is simple, purchased from plastic window manufacturers. Or maybe not simple...

A long search for aluminum corners, based on experience already tested by “colleagues,” ended in nothing.

Therefore, the manufacturing process began sluggishly, with a feeling of long-term construction.

I won’t describe the process of soldering panels, since there is a lot of information about this on the Internet and even a video. I'll just leave my notes and comments.

The devil is not as scary as he is painted.

Despite the difficulties that are described on the forums, the element plates are soldered easily, both the front side and the back. Also, our Soviet POS-40 solder is quite suitable, in any case, I did not experience any difficulties. And of course, our dear rosin, where would we be without it... During soldering I didn’t break a single element, I think you’d have to be a complete idiot to break them on even glass.

The conductors that come with the panels are very convenient, firstly, they are flat, and secondly, they are tinned, which significantly reduces soldering time. Although it is quite possible to use ordinary wire, I conducted the experiment on spare plates and did not experience any difficulties in soldering. (in the photo there are remains of a flat wire)

It took me about 2 hours to solder 36 plates. Although I read on the forum that people solder for 2 days.

It is advisable to use a 40 W soldering iron. Since the plates easily dissipate heat, and this makes soldering difficult. The first attempts to solder with a 25 Watt soldering iron were tedious and sad.

Also, when soldering, it is advisable to optimally select the amount of flux (rosin). For a large excess of it prevents the tin from sticking to the plate. That’s why we had to practically tin the record, in general, it’s no big deal, everything can be fixed. (look closely at the photo you can see.)

Tin consumption is quite large.

Well, in the photo there are soldered elements, there is a jamb in the second row, one terminal is not soldered, but I noticed nothing important and corrected it.

The glass edging is made with double-sided tape, then a plastic film will be glued to this tape.

The tapes I used.

After soldering, start sealing (adhesive tape will help you).

Well, the plates are glued with tape and the corrected jamb.

Next, remove the protective layer of double-sided tape from the edge of the panel and glue a plastic film onto it with a margin over the edges. (I forgot to take a photo) Oh yes, we make slits in the tape for the outgoing wires. Well, don’t be stupid, you’ll understand what and when... We coat the edges of the glass, as well as the wire leads, corners, with silicone sealant.

And fold the film onto the outside.

A plastic frame was previously made. When installed in the house plastic windows, a plastic profile for the window sill is attached to the window with screws. I thought this part was too thin. So I removed it and made the window sill my own way. Because only 12 windows remain plastic profiles. So to speak, there is an abundance of material.

I glued the frame with a regular, old, Soviet iron. It’s a pity I didn’t film the process, but I think there’s nothing too incomprehensible here. I cut 2 sides at 45 degrees, heated them on the sole of the iron and glued them after installing them on flat angle. The photo shows the frame for the second panel.

Installing glass with elements and protective film into the frame

We cut off the excess film and seal the edges with silicone sealants.

We get this panel.

Yes, I forgot to write that in addition to the film, I glued guides to the frame that prevent the elements from falling if the tape comes off. The space between the elements and guides is filled with polyurethane foam. This made it possible to press the elements more tightly to the glass.

Well, let's start testing.

Since I made one panel in advance, the result of one is known to me: Voltage 21 Volts. Short circuit current 3.4 Amperes. The battery charging current is 40A. h 2.1 Ampere.

Unfortunately I didn't take any photos. It must be said that the current strength depends sharply on the illumination.

Now there are 2 batteries connected in parallel.

The weather at the time of production was cloudy, it was about 4 o'clock in the afternoon.

At first it upset me, and then it even made me happy. After all, these are the most average conditions for a battery, which means the result is more plausible than in bright sunshine. The sun did not shine through the clouds so brightly. I must say that the sun was shining a little from the side.

With this lighting, the short circuit current was 7.12 Amperes. Which I consider an excellent result.

No-load voltage 20.6 Volts. Well, it's stable at about 21 volts.

Battery charging current is 2.78 Ampere. With such lighting, this guarantees the battery charge.

Measurements showed that on a good sunny day the result will be better.

By that time, the weather was getting worse, the clouds had closed, the sun was completely shining, and I began to wonder what would show in this situation. It's almost evening twilight...

The sky looked like this, I specially removed the horizon line. However, on the battery glass itself you can see the sky as if in a mirror.

The voltage in this situation is 20.2 volts. As already mentioned 21st century. it's practically a constant.

Short circuit current 2.48A. In general, it’s great for such lighting! Almost equal to one battery in good sun.

Battery charging current is 1.85 Ampere. What can I say... Even at dusk the battery will be charged.

Conclusion: A solar battery has been built that is not inferior in characteristics to industrial designs. Well, as for durability.....we'll see, time will tell.

Oh yes, the battery is charged through 40 A Schottky diodes. Well, what was found.

I also want to say about controllers. It all looks nice, but it's not worth the money spent on the controller.

If you are comfortable with a soldering iron, the circuits are very simple. Do it and enjoy making it.

Well, the wind blew up and the remaining 5 spare elements went into an uncontrollable flight..... the result was fragments. Well, what can you do, carelessness must be punished. On the other hand... Where should they go?

We decided to make another socket from the fragments, 5 volts. It took 2 hours to make. The remaining materials came at just the right time. This is what happened.

Measurements were taken in the evening.

It must be said that in good lighting the short circuit current is more than 1 ampere.

The pieces are soldered in parallel and in series. The goal is to provide approximately the same area. After all, the current strength is equal to the smallest element. Therefore, when manufacturing, select elements according to the lighting area.

It's time to talk about the practical application of the solar panels I made.

In the spring I installed two manufactured panels on the roof, 8 meters high at an angle of 35 degrees, oriented to the southeast. This orientation was not chosen by chance, because it was noticed that in this latitude, in the summer, the sun rises at 4 am and by 6-7 o’clock it charges the batteries quite well with a current of 5-6 amperes, and this also applies to the evening. Each panel must have its own diode. In order to prevent elements from burning out when the power of the panels differs. And as a consequence, an unjustified reduction in the power of the panels.
The descent from a height was carried out with multi-core wire with a cross-section of 6 mm2 each core. In this way, it was possible to achieve minimal losses in the wires.

Old, barely alive batteries 150Ah, 75Ah, 55Ah, 60Ah were used as energy storage devices. All batteries are connected in parallel and, taking into account the loss of capacity, the total amount is about 100Ah.
There is no battery charge controller. Although I think installing a controller is necessary. I’m working on the controller circuit now. Since during the day the batteries begin to boil. Therefore, you have to dump excess energy every day by turning on unnecessary load. In my case, I turn on the bathhouse lighting. 100 W. Also, during the day, an LCD TV of approximately 105W, a 40W fan, and in the evening an energy-saving 20W light bulb are added.

For those who like to carry out calculations, I will say: THEORY AND PRACTICE are not the same thing. Since such a “sandwich” works quite well for over 12 hours. At the same time, sometimes we charge phones from it. I have never reached the full discharge of the batteries. Which accordingly cancels out the calculations.

As a converter, a 600VA computer uninterruptible power supply (inverter) was used, slightly modified for free starting from batteries, which approximately corresponds to a load of 300W.
I also want to note that the batteries are charged even under a bright moon. In this case, the current is 0.5-1 Ampere, I think for the night this is not bad at all.

Of course, I would like to increase the load, but this requires a powerful inverter. I plan to make an inverter myself according to the diagram below. Since buying an inverter for crazy money is UNREASONABLE!

Over the years, the comfort of living in the houses and apartments of modern people requires more and more electricity. But in modern conditions The cost of each unit of electricity is steadily increasing, which, accordingly, affects costs. Therefore, the issue of switching to alternative sources of electricity is the most pressing. One way to ensure independence in obtaining electricity is the ability to use solar panels for this purpose at home.

An effective alternative or a general misconception?

Talk about self-powering household appliances and lighting in houses using solar energy have been carried out since the middle of the last century. The development of technology and general progress have made it possible to bring this technology closer to the ordinary consumer. The statement that using solar panels for your home will become quite effective way replacement of traditional energy networks could be considered indisputable, if not for a couple of significant “buts”.

The main requirement for the efficiency of using gel batteries is the amount of solar energy. Device solar battery allows you to effectively use the energy of our luminary only in regions where it is sunny most of the year. It is also necessary to take into account the latitude at which solar panels are mounted - the higher the latitude, the less power the sun's ray has. Ideally, an efficiency of about 40% can be achieved. But this is ideal, but in practice everything is somewhat different.

The next point worth paying attention to is the need to use large enough areas to allow the installation of autonomous solar panels. If the batteries are planned to be placed on summer cottage, country house, cottage, then there will be no problems here, but for those living in apartment buildings you will have to think about this seriously.

Solar battery - what is it?

The solar battery is based on the ability of photocells to convert solar energy into electricity. United in common system, these converters create a multi-cell field, each cell of which, under the influence of solar energy, becomes a source of electric current, which is then accumulated in special devices - batteries. Of course, the larger the given field, the higher the power of such a device. That is, the more photocells it contains, the more electricity it can produce.

But this does not mean that only huge areas where it is possible to install solar panels can provide the necessary electricity. There are many gadgets that can work not only from the usual autonomous power sources - batteries, rechargeable batteries - but also use solar energy. Portable solar panels are built into the design of such devices, making it possible to both recharge the device and work autonomously. For example, an ordinary pocket calculator: in sunny weather, placing it on the table can recharge the battery, which extends its service life by long years. There are a lot various devices, where such batteries are used: these are pen-flashlights, flashlights-keychains, etc.

In summer cottages and suburban areas, it has recently become fashionable to use solar-powered lanterns for lighting. An economical and uncomplicated device provides lighting along garden paths, on terraces and in all necessary places, using electricity accumulated during daylight hours when the sun is shining. Economical lighting lamps are able to consume this energy for quite a long time, which ensures great interest in such devices. Solar-powered lighting is also used in houses, cottages, and utility rooms.

Types of off-grid solar panels

There are two types of solar energy converters, depending on the design of the battery itself - film and silicon. The first type includes thin-film batteries, in which the converters are a film made using a special technology. They are also called polymer. Such batteries can be installed in any accessible location, but have several disadvantages: they require a lot of space, have a low efficiency, and even with average cloudiness, their energy efficiency drops by 20 percent.

Silicon type solar cells are represented by monocrystalline and polycrystalline devices, as well as amorphous silicon panels. Monocrystalline batteries consist of many cells containing silicon converters, connected into a common circuit and filled with silicone. Easy to operate, with high (up to 22%) efficiency, waterproof, lightweight and flexible, but require direct solar flow to operate effectively. Cloudy weather can cause a complete loss of power generation.

Polycrystalline batteries differ from monocrystalline batteries in the number of converters placed in each cell and installed in different directions, which ensures their efficient operation even in diffuse light. This is the most common type of battery, which is also used in urban environments, although its efficiency is somewhat lower than that of monocrystalline batteries.

Amorphous silicon power supplies, despite their low energy efficiency - about 6%, are nevertheless considered more promising. They absorb solar flux twenty times more than silicon ones, and are much more effective on cloudy days.

All these are industrial devices that have their own - and currently not very affordable - price. Is it possible to assemble solar panels with your own hands?

General principle of selection and arrangement of parts for solar panels

In connection with the latest requirements for the production of electrical energy, which are aimed at transitioning from the traditional raw materials used in its production, the topic of solar power sources is becoming increasingly practical. Mass production of elements for creating your own electrical network already offers consumers various options provision of autonomous electricity. But the cost of an autonomous solar power source is still quite high and inaccessible to the mass consumer.

But this does not mean that you cannot make solar panels with your own hands. In this case, you just need to decide on the method of assembling such a device. Or, purchasing individual elements, assemble them yourself, or make all the components yourself.

What exactly does a power system based on converting solar energy into electric current consist of? The main, but not the last of its elements is the solar battery, the design of which was discussed above. The second element in the circuit is the solar battery controller, whose task is to control the charging of the batteries with the electric current obtained in the solar panels. The next part of a home solar power plant is a battery of electric batteries, in which electricity is stored. And the last element of the “solar” electrical circuit There will be an inverter that will allow the resulting low-voltage electricity to be used for household appliances designed for 220 V.

Considering each element of a home solar power plant separately, you can see that each element can be purchased in a retail network, at electronic auctions, etc., or assembled with your own hands. And you can even make a solar battery controller with your own hands - if you have certain skills and theoretical knowledge.

Now regarding the tasks that are set for our own power plant. They are simple and complex at the same time. Their simplicity lies in the fact that solar energy is used for specific purposes: lighting, heating or fully meeting the needs of the home. The difficulty lies in the correct calculation of the required power and the appropriate selection of components.

Let's start assembling the solar panel

Now you can find a lot of proposals on how and from what you can assemble solar panels. There are many ways, and you can choose according to your preference. This material discusses the basic principles that must be used when making solar panels with your own hands.

First of all, you need to decide on the power that needs to be obtained and decide at what voltage the network will operate. There are two options for solar energy networks - with direct current and alternating current. Alternating current is more preferable due to the possibility of distributing electricity consumers over a considerable distance - more than 15 meters. This is just right for a small house. Without going deeply into calculations and starting from the experience of those who already use solar energy at their dachas, we can confidently say that at the latitudes of Moscow - and going further south, these figures will naturally be higher - one square meter of solar panels can produce up to 120 watts per hour. This is if you use polycrystalline elements during assembly. They are more attractively priced. And it is quite possible to determine the total power by adding up the entire power consumption of each individual electrical appliance. Very roughly, we can say that for a family of 3-4 people, about 300 kilowatts per month are required, which can be obtained from solar panels of 20 square meters. meters.

You can also find descriptions of solar-powered networks using panels of 36 elements. Each panel has a power of about 65 watts. A solar battery for a country house or a small private house can consist of 15 such panels, which are capable of generating up to 5 kW per hour of total electrical power, having its own power of 1 kW.

DIY solar panels

And now about how to make a solar battery. The first thing you will have to purchase will be a set of conversion plates, the number of which depends on the power of the homemade solar power plant. For one battery you will need 36 pieces. You can use the Solar Cells kit, or purchase damaged or defective cells - this will only affect the appearance of the battery. If they are working, then the output will be almost 19 Volts. They need to be soldered taking into account expansion - leaving a gap of up to five millimeters between them. Building a solar battery with your own hands requires extreme care when soldering photographic plates. If the plates were purchased without conductors, then they must be soldered manually. The process is complex and responsible. If the work is done with a 60 W soldering iron, it is best to connect a simple 100-watt light bulb in series with it.

The solar battery circuit is very simple - each plate is soldered to the others in series. It is worth noting that the plates are very fragile, and it is advisable to solder them using some kind of frame. When unsoldering photographic plates, it is also necessary to remember that safety diodes must be inserted into the circuit to prevent the discharge of photocells when darkening or decreasing illumination. To do this, the buses of the panel halves are brought out to the terminal block, creating a midpoint. These diodes also prevent batteries from discharging at night.

Soldering quality is the main requirement for the flawless operation of solar panels. Before installing the substrate, all solder joints must be tested. It is recommended to output current using small cross-section wires. For example, an acoustic cable with silicone insulation. All conductors must be secured with sealant.

Then you need to decide on the surface on which these plates will be attached. Or rather, with the material for its manufacture. The most suitable in terms of characteristics and easily accessible is glass, which has a maximum throughput luminous flux compared to plexiglass or carbonate.

The next step will be making the box. For this, an aluminum corner or a wooden beam is used. Glass is placed in the frame using sealant - it is advisable to carefully fill all the irregularities. It should be noted that the sealant must dry completely to avoid contamination of the photographic plates. Then a finished sheet of soldered photocells is attached to the glass. The method of fastening may vary, but solar panels for the home, reviews of which are common, were fixed mainly using transparent epoxy resin or sealant. If epoxy is applied evenly over the entire surface of the glass, after which transducers are placed on it, then the sealant is attached mainly to a drop in the middle of each element.

Various materials are used for the substrate, which is also attached to the sealant. These can be thin chipboards or fiberboard sheets. Although you can, again, fill it with epoxy resin. The battery case must be sealed. A do-it-yourself solar battery made in this way, the assembly diagram of which was discussed above, will provide 18-19 Volts, ensuring charging of a 12-volt battery.

Is it possible to make a solar energy converter with your own hands?

Craftsmen with extensive knowledge of electronics can make photovoltaic cells to convert solar energy into electricity on their own. For this purpose, silicon diodes are used, or rather their crystals, freed from their cases. This process is labor-intensive, and everyone decides for themselves whether to start it or not. You can take diodes used in bridge circuits of voltage rectifiers and stabilizers - D226, KD202, D7, etc. The semiconductor crystal located in these diodes, when exposed to sunlight, becomes exactly the same as a photographic plate. But getting to it without damaging it is a rather complex and painstaking process.

Anyone who decides to start creating elements for the converter on their own should remember the following - if you managed to carefully disassemble and solder a battery consisting of only twenty diodes of the KD202 brand according to a circuit of 5 groups connected in parallel, then you can get a voltage of about 2 V with a current of up to 0. 8 Amps. This power is only enough to power a small radio receiver, which has only one or two transistors in its circuit. But to turn them into a full-fledged solar battery for a summer house, you need to try very hard. Huge work, large areas, the bulkiness of the design makes this activity futile. But for small devices and gadgets, this is a completely suitable design that can be made by anyone who likes to do electrical engineering.

Can LEDs be used for solar panels?

The LED solar cell is pure fiction. It is almost impossible to assemble even a small solar micropanel from LEDs. Or rather, it is possible to create it, but is it worth it? Using sunlight, it is quite possible to get about 1.5 volts of voltage across the LED, but the current generated is very small, and only very strong sun is required to generate it. And one more thing - when voltage is applied to it, the LED itself emits radiation energy, that is, it glows. This means that those of its brothers, which were hit by sunlight of greater intensity, will generate electricity, which this LED itself will consume. Everything is correct and simple. And it is simply impossible to figure out which LEDs produce and which consume energy. Even if you use tens of thousands of LEDs - and this is impractical and uneconomical - there will be no benefit.

We heat the house with solar energy

If the real possibility of providing household electrical appliances with “solar” current has already been mentioned above, then there are two options for heating a home with solar energy. And in order to use solar panels to heat your home, you need to know some of the requirements that are mandatory to complete this task.

In the first option, solar energy is used for heating using a system other than the conventional electrical network. A home heating device that uses solar energy is called a solar system and consists of several devices. The main working device is a vacuum collector, which converts sunlight into heat. It consists of many small diameter glass tubes into which a liquid with a very low heating threshold is placed. When heated, this liquid subsequently transfers its heat to water in a storage tank with a volume of at least 300 liters of water. This heated water is then fed to heating panels made of thin copper pipes, which, in turn, release the resulting heat, warming the air in the room. Instead of panels, you can, of course, use traditional radiators, but their efficiency is much lower.

Of course, solar panels can also be used for heating, but in this case you will need to agree that heating the water in the boiler using heating elements will require the lion's share of the energy generated by the batteries. Simple calculations show that it takes about 4 hours for a boiler to heat 100 liters of water to 70-80 ⁰C. During this time, a water boiler with 2 kW heaters will consume about 8 kW. If solar panels can generate up to 5 kW per hour in total power, then there will be no problems with energy supply in the house. But if the solar panels have an area of ​​less than 10 square meters. meters, then such capacities are not suitable for full provision of electrical energy.

The use of a vacuum collector for heating a house is justified when it is a full-fledged residential building. The operating scheme of such a solar system provides heat to the entire home throughout the year.

And yet it works!

In the end, solar panels, assembled by enthusiasts with their own hands, are very real power sources. And if you use 12-volt batteries in the circuit with a current of at least 800 A/h, equipment for converting voltage from low to high - inverters, as well as 24 V voltage controllers with an operating current of up to 50 Amperes and a simple “uninterruptible power supply” with a current of up to 150 Amperes, then you get a very decent solar power plant, which is capable of meeting the electricity needs of residents of a private house. Naturally, under certain weather conditions.

The desire to make the energy supply system of a private home more efficient, economical and environmentally friendly makes us look for new energy sources. One of the modernization methods is to install solar panels capable of converting the sun's energy into electricity. There is an excellent alternative to expensive equipment - a do-it-yourself solar battery, which will allow you to save money every month from family budget. Today we will talk about how to build such a thing. We will identify all the pitfalls and tell you how to get around them.

For general information about the design features of solar panels, watch the video:

Development of a solar energy system project

Design is necessary for more successful placement of panels on the roof of the house. The more sunlight hits the surface of the batteries and the higher their intensity, the more energy they will produce. For installation you will need the south side of the roof. Ideally, the beams should fall at an angle of 90 degrees, so it is necessary to determine in which position the operation of the modules will bring more benefit.

The fact is that a homemade solar battery, unlike a factory one, does not have special motion sensors and concentrators. To change the angle of inclination, it is possible to manufacture a manually controlled mechanism. It will allow the modules to be installed almost vertically in winter, when the sun is low above the horizon, and lowered in summer, when the solstice reaches its peak. The vertical winter arrangement also has a protective function: it prevents snow and ice from accumulating on the panels, thereby extending the life of the modules.

The energy efficiency of a modular design can be increased by creating a simple control mechanism that allows you to change the angle of the battery depending on the time of year and even time of day

It is possible that before installing the batteries, the roof structure will need to be strengthened, since a set of several panels has a fairly large mass. It is necessary to calculate the load on the roof, taking into account the weight of not only the solar panels, but also the snow layer. The weight of the system largely depends on the materials used in its manufacture.

The number of panels and their size are calculated based on the required power. For example, 1 m² of module produces approximately 120 W, which is not enough even for full lighting of residential premises. Approximately 1 kW of energy with 10 m² of panels will allow the functioning of lighting fixtures, a TV and a computer. Accordingly, a solar structure of 20 m² will meet the needs of a family of 3 people. Approximately these dimensions should be calculated if a private house intended for permanent residence.

The manufacture of a solar battery does not necessarily end with the initial assembly; in the future, the elements can be expanded, thereby increasing the efficiency of the equipment

Module options for self-assembly

The main purpose of a solar panel is to generate energy from the sun's rays and convert it into electricity. The resulting electric current is a stream of free electrons released by light waves. For self-assembly, the best option is mono- and polycrystalline converters, since analogues of another type - amorphous - reduce their power by 20-40% during the first two years.

Standard monocrystalline cells measure 3 x 6 inches and have a rather fragile structure, so they must be handled with extreme care and precision

Different types of silicon wafers have their pros and cons. For example, polycrystalline modules have a rather low efficiency - up to 9%, while the efficiency of monocrystalline wafers reaches 13%. The former maintain their power levels even in cloudy weather, but last an average of 10 years, the power of the latter drops sharply on cloudy days, but they function perfectly for 25 years.

A homemade device must be functional and reliable, so it is better to purchase some parts ready-made. Before making a custom solar panel, take a look at eBay, where you can find a huge selection of modules with minor defects. Slight damage does not affect the quality of work, but significantly reduces the cost of the panels. Let's say a monocrystalline Solar Cells module located on a fiberglass board costs a little more than $15, and a polycrystalline set of 72 pieces costs about $90.

The best ready-made solar cell option is a panel with conductors that only require a series connection. Modules without conductors are cheaper, but increase battery assembly time several times

Instructions for making a solar battery

There are many options for self-assembly of solar panels. The technology depends on the number of solar cells purchased in advance, and additional materials, necessary for the manufacture of the body. It is important to remember: the more total area panels, the more powerful the equipment, but at the same time the weight of the structure increases. It is recommended to use identical modules in one battery, since the current equivalence is equal to the indicators of the smaller of the elements.

Assembling a modular frame

The design of the modules, as well as their dimensions, can be arbitrary, so instead of numbers, you should rely on the photo and choose any individual option suitable for specific calculations.

The cheapest solar cells are panels without conductors. To make them ready for battery assembly, the conductors must first be soldered, which is a long and painstaking process.

To manufacture the housing inside which the solar cells will be fixed, it is necessary to prepare the following material and tools:

• sheets of plywood of the selected size;
• low slats for sides;
• universal glue or for wood;
• corners and screws for fastening;
• drill;
• fiberboard boards;
• pieces of plexiglass;
• dye.

We take a piece of plywood that will act as a base, and glue low sides around the perimeter. The slats along the edges of the sheet should not block the solar cells, so make sure that their height does not exceed ¾ inches. For reliability, each glued rail is additionally screwed with self-tapping screws, and the corners can be fastened with metal corners.

Wooden frame is the most affordable option for placement of solar cells. It can be replaced with an aluminum corner frame or a purchased frame + glass set

For ventilation, we drill holes in the bottom of the case and along the sides. There should be no holes in the lid, as this could result in moisture getting in. The elements will be fastened to fiberboard sheets, which can be replaced by any similar material, the main condition is that it should not conduct electric current.

Small holes for ventilation must be drilled throughout the entire area of ​​the substrate, including the sides and the middle rail. It will allow you to regulate the level of moisture and pressure inside the frame

We cut out the cover from plexiglass, adjusting it to the dimensions of the body. Regular glass is too fragile to be placed on a roof. To protect the wooden parts, we use a special impregnation or paint, which should be used to treat the frame and substrate on all sides. It would be nice if the shade of the frame paint matches the color of the roofing.

Painting serves not so much an aesthetic function as a protective one. Each part should be coated with at least 2-3 layers of paint to prevent the wood from being warped by humid air or overheating in the future.

Installation of solar cells

We lay out all solar modules in even rows on the substrate, back side up, to solder the conductors. To work you will need a soldering iron and solder. Soldering areas must first be treated with a special pencil. To begin with, you can practice on two elements, connecting them in series. We also connect all the elements on the substrate sequentially, in a chain, and the result should be a “snake”.

We install each element strictly according to the markings and make sure that the conductors of neighboring elements intersect at the soldering points

Having connected all the elements, carefully turn them face up. If there are many modules, you will have to invite helpers, since it is quite difficult to turn the soldered elements without damaging them alone. But before that, we coat the modules with glue to secure them firmly to the panel. It is better to use silicone sealant as glue, and it should be applied strictly in the center of the element, at one point, and not along the edges. This is necessary to protect the plates from breakage if a slight deformation of the base suddenly occurs. A sheet of plywood can bend or swell due to changes in humidity, and the stably glued elements will simply crack and fail.

Having secured the modules to the substrate, you can test run the panel and check the functionality. Then we place the base in the finished frame and fix it along the edges with screws. To prevent the battery from discharging through the solar panel, we install a blocking diode on the panel, securing it with sealant.

To connect the chains, you can use copper wire or cable braid, which fix each element on both sides and then seal it with sealant

Trial testing helps make preliminary calculations. In this case, they turned out to be correct - in the sun without load, the battery produces 18.88 V

We cover the installed elements on top with a protective plexiglass screen. Before fixing it, we again check the functionality of the structure. By the way, you can test modules during the entire installation and soldering process, in groups of several pieces. We make sure that the sealant dries completely, since its fumes can cover the plexiglass with an opaque film. We equip the output wire with a two-pin connector so that the controller can be used in the future.

One panel is assembled and completely ready for use. All equipment, including items purchased online, cost $105

Photovoltaic systems of a private house

Electrical home energy supply systems using solar cells can be divided into 3 types:

• autonomous;
• hybrid;
• battery-free.

If the house is connected to the central power grid, then the best option would be a mixed system: during the day the power is supplied from solar panels, and at night from batteries. The central network in this case is a reserve. When it is not possible to connect to the central power supply, it is replaced with fuel generators - gasoline or diesel.

A controller is needed to prevent short circuits at the moment of maximum load, a battery is needed to store energy, an inverter is needed to distribute and supply it to the consumer.

When choosing the most successful option, you should take into account the time of day at which maximum energy consumption occurs. In private homes, the peak period falls in the evening, when the sun has already set, so it would be logical to use either a connection to the public network or the additional use of generators, since solar energy supply occurs during the daytime.

Photovoltaic power supply systems use networks with both direct and alternating current, and the second option is suitable for placing devices at a distance of more than 15 m

For summer residents, whose operating hours often coincide with daylight hours, a solar energy-saving system is suitable, which begins to function at sunrise and ends in the evening.

Living in the “Organic” style, such a popular idea in recent years, presupposes a harmonious “relationship” between a person and the environment. The stumbling block to any environmental approach is the use of minerals for energy.

Emissions of toxic substances and carbon dioxide into the atmosphere released during the combustion of fossil fuels are gradually killing the planet. Therefore, the concept of "green energy" that does not harm environment, is the basic basis of many new energy technologies. One of these areas for obtaining environmentally friendly energy is the technology of converting sunlight into electric current. Yes, that’s right, we will talk about solar panels and the possibility of installing autonomous energy supply systems in a country house.

At the moment, industrial power plants based on solar panels, used for the complete energy and heat supply of a cottage, cost at least 15-20 thousand dollars with a guaranteed service life of about 25 years. The cost of any helium system in recalculation of the ratio of the guaranteed service life to the average annual cost of utility maintenance of a country house is quite high: firstly, today the average cost of solar energy is comparable to the purchase of energy resources from central power grids, and secondly, one-time capital investments are required to install the system .

It is usually customary to separate solar systems intended for heat and energy supply. In the first case, technology is used solar collector, in the second - the photoelectric effect for generating electric current in solar panels. We want to talk about the possibility of making solar panels yourself.

Technology hand assembled The solar energy system is quite simple and affordable. Almost every Russian can assemble individual energy systems with high efficiency at relatively low costs. It's profitable, affordable and even fashionable.

Selecting solar cells for a solar panel

When starting to manufacture a solar system, you need to pay attention that with individual assembly there is no need for a one-time installation of a fully functional system; it can be expanded gradually. If the first experience was successful, then it makes sense to expand the functionality of the solar system.

At its core, a solar battery is a generator that operates on the basis of the photovoltaic effect and converts solar energy into electrical energy. Quanta of light striking a silicon wafer knock an electron out of the last atomic orbit of silicon. This effect creates a sufficient number of free electrons to form a flow of electric current.

Before assembling the battery, you need to decide on the type of photoelectric converter, namely: monocrystalline, polycrystalline and amorphous. To assemble a solar battery yourself, choose commercially available monocrystalline and polycrystalline solar modules.

Above: Monocrystalline modules without soldered contacts. Bottom: Polycrystalline modules with soldered contacts

Panels based on polycrystalline silicon have a fairly low efficiency (7-9%), but this disadvantage is offset by the fact that polycrystals practically do not reduce power in cloudy and cloudy weather; the guaranteed durability of such elements is about 10 years. Panels based on monocrystalline silicon have an efficiency of about 13% with a service life of about 25 years, but these elements greatly reduce power in the absence of direct sunlight. Efficiency indicators of silicon crystals from different manufacturers may vary significantly. Based on the practice of operating solar power plants in field conditions, we can say that the service life of monocrystalline modules is more than 30 years, and for polycrystalline modules - more than 20 years. Moreover, over the entire period of operation, the power loss for silicon mono- and polycrystalline cells is no more than 10%, while for thin-film amorphous batteries the power decreases by 10-40% in the first two years.

Evergreen Solar Cells with contacts in a set of 300 pcs.

At the eBay auction you can purchase a Solar Cells kit for assembling a solar battery of 36 and 72 solar cells. Such sets are also available for sale in Russia. As a rule, for self-assembly of solar panels, B-type solar modules are used, that is, modules rejected in industrial production. These modules do not lose their performance characteristics and are much cheaper. Some suppliers offer solar modules on a fiberglass board, which implies high level tightness of elements, and, accordingly, reliability.

Name	Characteristics	Cost, $
Everbright Solar Cells (Ebay) no contacts	polycrystalline, set - 36 pcs., 81x150 mm, 1.75 W (0.5 V), 3A, efficiency (%) - 13 in a set with diodes and acid for soldering in a pencil	$46.00 $8.95shipping
Solar Cells (USA new)	monocrystalline, 156x156 mm, 81x150 mm, 4W (0.5 V), 8A, efficiency (%) - 16.7-17.9	$7.50
	monocrystalline, 153x138 mm, U cold. stroke - 21.6V, I short. deputy - 94 mA, P - 1.53W, efficiency (%) - 13	$15.50
Solar Cells on a fiberglass board	polycrystalline, 116x116 mm, U cold. stroke - 7.2V, I short. deputy - 275 mA., P - 1.5W, efficiency (%) - 10	$14.50
		$87.12 $9.25 shipping
Solar Cells (Ebay) without contacts	polycrystalline, set - 72 pcs., 81x150 mm 1.8W	$56.11 $9.25 shipping
Solar Cells (Ebay) with contacts	monocrystalline, set - 40 pcs., 152x152 mm	$87.25 $14.99 shipping

Development of a helium energy system project

The design of a future solar system largely depends on the method of its installation and installation. Solar panels should be installed at an angle to ensure direct sunlight at right angles. The performance of a solar panel largely depends on the intensity of the light energy, as well as the angle of incidence of the sun's rays. The placement of the solar battery relative to the sun and the angle of inclination depend on the geographical location of the helium system and the time of year.

From top to bottom: Monocrystalline solar panels (80 watts each) at the dacha are installed almost vertically (winter). Monocrystalline solar panels in the country have a smaller angle (spring). Mechanical system for controlling the angle of the solar battery.

Industrial solar systems are often equipped with sensors that ensure the rotational movement of the solar panel in the direction of movement of the sun's rays, as well as solar concentrator mirrors. In individual systems, such elements significantly complicate and increase the cost of the system, and therefore are not used. A simple mechanical tilt angle control system can be used. In winter, solar panels should be installed almost vertically; this also protects the panel from snow accumulation and icing of the structure.

Scheme for calculating the angle of inclination of a solar panel depending on the time of year

Solar panels are installed on the sunny side of the building to provide the maximum amount of solar energy available during daylight hours. Depending on your geographic location and solstice level, the battery angle that is most suitable for your location is calculated.

If the design becomes more complex, it is possible to create a system for controlling the angle of inclination of the solar battery depending on the time of year and the angle of rotation of the panel depending on the time of day. The energy efficiency of such a system will be higher.

When designing a solar system that will be installed on the roof of a house, it is necessary to find out whether roof structure maintain the required weight. Independent development of the project involves calculating the roof load taking into account the weight of the snow cover in winter.

Selecting the optimal static tilt angle for a monocrystalline type roofing solar system

For the manufacture of solar panels, you can choose various materials according to specific gravity and other characteristics. When choosing construction materials, it is necessary to take into account the maximum permissible heating temperature of the solar cell, since the temperature of a solar module operating at full power should not exceed 250C. Once the peak temperature is exceeded, the solar module abruptly loses its ability to convert sunlight into electrical current. Ready-made solar systems for individual use, as a rule, do not require cooling of solar cells. Do-it-yourself manufacturing may involve cooling the solar system or controlling the angle of the solar panel to ensure the functional temperature of the module, as well as selecting the appropriate transparent material, absorbing IR radiation.

Proper design of the solar system allows you to provide the required power of the solar battery, which will be close to the nominal one. When calculating a structure, it must be taken into account that elements of the same type give the same stress, regardless of the size of the elements. Moreover, the current strength of large-sized elements will be greater, but the battery will also be much heavier. To manufacture a solar system, solar modules of the same size are always taken, since the maximum current will be limited by the maximum current of the small element.

Calculations show that on average on a clear sunny day you can get no more than 120 W of power from 1 m of solar panel. Such power will not even power a computer. A 10 m system provides more than 1 kW of energy and can provide electricity for the operation of basic household appliances: lamps, TV, computer. For a family of 3-4 people, about 200-300 kW per month is needed, so a solar system installed on the south side, 20 m in size, can fully meet the family's energy needs.

If we consider the average statistical data on the power supply of an individual residential building, then: daily energy consumption is 3 kWh, solar radiation from spring to autumn is 4 kWh/m per day, peak power consumption is 3 kW (when turned on). washing machine, refrigerator, iron and electric kettle). In order to optimize energy consumption for lighting inside the house, it is important to use AC lamps with low energy consumption - LED and fluorescent.

Making a solar battery frame

An aluminum corner is used as the frame of the solar battery. At the eBay auction you can purchase ready-made frames for solar panels. The transparent coating is selected at will, based on the characteristics that are necessary for a given design.

Solar panel frame kit with glass, starting at $33

When choosing a transparent protective material, you can also focus on the following material characteristics:

Material	Refractive index	Light transmittance, %	Specific gravity g/cm 3	Sheet size, mm	Thickness, mm	Cost, rub./m2
Air	1,0002926	—	—	—	—	—
Glass	1,43-2,17	92-99	3,168	—	—	—
Plexiglas	1,51	92-93	1,19	3040x2040	3	960.00
Polycarbonate	1,59	up to 92	0,198	3050 x2050	2	600.00
Plexiglass	1,491	92	1,19	2050x1500	11	640.00
Mineral glass	1,52-1,9	98	1,40	—	—	—

If we consider the refractive index of light as a criterion for choosing a material. Plexiglas has the lowest refractive index; a cheaper option for transparent material is domestic plexiglass, and polycarbonate is less suitable. Polycarbonate with an anti-condensation coating is available for sale; this material also provides a high level of thermal protection. When choosing transparent materials based on specific gravity and ability to absorb the IR spectrum, polycarbonate will be the best. The best transparent materials for solar panels include those with high light transmittance.

When manufacturing a solar battery, it is important to choose transparent materials that do not transmit the IR spectrum and, thus, reduce the heating of silicon elements, which lose their power at temperatures above 250C. In industry, special glasses with a metal oxide coating are used. The ideal glass for solar panels is considered to be a material that transmits the entire spectrum except the infrared range.

Diagram of absorption of UV and IR radiation by various glasses.
A) ordinary glass, b) glass with IR absorption, c) duplex with heat-absorbing and ordinary glass.

Maximum absorption of the IR spectrum will be provided by protective silicate glass with iron oxide (Fe 2 O 3), but it has a greenish tint. The IR spectrum is well absorbed by any mineral glass with the exception of quartz; plexiglass and plexiglass belong to the class of organic glasses. Mineral glass is more resistant to surface damage, but is very expensive and unavailable. For solar panels, special anti-reflective, ultra-transparent glass is also used, transmitting up to 98% of the spectrum. This glass also assumes absorption of most of the IR spectrum.

The optimal choice of optical and spectral characteristics of glass significantly increases the photoconversion efficiency of the solar panel.

Solar panel in plexiglass housing

Many solar panel workshops recommend using plexiglass for the front and back panels. This allows contact inspection. However, a plexiglass structure can hardly be called completely sealed, capable of ensuring uninterrupted operation of the panel for 20 years of operation.

Installation of the solar battery housing

The master class shows how to make a solar panel from 36 polycrystalline solar cells measuring 81x150 mm. Based on these dimensions, you can calculate the size of the future solar battery. When calculating the dimensions, it is important to make a small distance between the elements, which will take into account the change in the size of the base under atmospheric influence, that is, there should be 3-5 mm between the elements. The resulting workpiece size should be 835x690 mm with a corner width of 35 mm.

	A homemade solar panel made using an aluminum profile is most similar to a factory-made solar panel. This ensures a high degree of tightness and structural strength.
	For manufacturing, an aluminum corner is taken, and frame blanks of 835x690 mm are made. To allow fastening of hardware, holes should be made in the frame.
	Silicone sealant is applied twice to the inside of the corner.
	Be sure to make sure there are no empty spaces. The tightness and durability of the battery depends on the quality of application of the sealant.
	Next, a transparent sheet of the selected material is placed in the frame: polycarbonate, plexiglass, plexiglass, anti-reflective glass. It is important to let the silicone dry in the open air, otherwise the fumes will create a film on the elements.
	The glass must be carefully pressed and fixed.
	To securely attach the protective glass, you will need hardware. You need to secure the 4 corners of the frame and place two hardware around the perimeter on the long side of the frame and one hardware on the short side.
	The hardware is fixed with screws.
	The screws are tightened tightly using a screwdriver.
	The solar battery frame is ready. Before attaching solar cells, it is necessary to clean the glass from dust.

Selection and soldering of solar cells

Currently, the eBay auction offers a huge range of products for making solar panels yourself.

Solar Cells kit includes a set of 36 polycrystalline silicon cells, cell leads and busbars, Schottke diodes and a soldering acid pen

Since a solar battery made by yourself is almost 4 times cheaper than a ready-made one, making it yourself is a significant cost saving. You can buy solar cells on eBay that have defects, but they do not lose their functionality, so the cost of a solar panel can be significantly reduced if you can sacrifice the appearance of the battery.

Damaged photocells do not lose their functionality

For your first experience, it is better to purchase kits for making solar panels; solar cells with soldered conductors are available for sale. Soldering contacts is a rather complex process, the complexity of which is compounded by the fragility of solar cells.

If you purchased silicon elements without conductors, you must first solder the contacts.

	This is what a polycrystalline silicon cell looks like without conductors.
	The conductors are cut using a cardboard blank.
	It is necessary to carefully place the conductor on the photocell.
	Apply soldering acid and solder to the soldering area. For convenience, the conductor is fixed on one side with a heavy object.
	In this position, it is necessary to carefully solder the conductor to the photocell. While soldering, do not press on the crystal because it is very fragile.

Soldering elements is quite a painstaking job. If you cannot get a normal connection, you need to repeat the work. According to standards, silver coating on a conductor must withstand 3 soldering cycles under acceptable thermal conditions, but in practice you are faced with the fact that the coating is destroyed. The destruction of silver plating occurs due to the use of soldering irons with unregulated power (65 W), this can be avoided if you lower the power as follows - you need to turn on a socket with a 100 W light bulb in series with the soldering iron. The power rating of a non-regulated soldering iron is too high for soldering silicon contacts.

Even if conductor sellers claim that there is solder on the connector, it is better to apply it additionally. When soldering, try to handle the elements carefully; with minimal force they will burst; Do not stack the elements in a stack; the weight may cause the lower elements to crack.

Assembling and soldering a solar battery

At the first self-assembly It is better to use a marking substrate for the solar battery, which will help position the elements exactly at a certain distance from each other (5 mm).

Marking substrate for solar battery cells

The base is made of a sheet of plywood with corner markings. After soldering, a piece of mounting tape is attached to each element on the reverse side; just press the back panel against the tape, and all elements are transferred.

Mounting tape used for mounting on the back of the solar cell

With this type of fastening, the elements themselves are not additionally sealed; they can expand freely under the influence of temperature, this will not damage the solar battery or break the contacts and elements. Only the connecting parts of the structure can be sealed. This type of fastening is more suitable for prototypes, but can hardly guarantee long-term operation in the field.

The sequential battery assembly plan looks like this:

	Lay out the elements on glass surface. There must be a distance between the elements, which allows for free changes in size without damaging the structure. The elements must be pressed with weights.
	We carry out soldering according to the electrical diagram below. “Positive” current-carrying paths are located on the front side of the elements, “negative” ones - on the back side. Before soldering, you need to apply flux and solder, then carefully solder the silver contacts.
	All solar cells are connected using this principle.
	The contacts of the outer elements are output to the bus, respectively, to “plus” and “minus”. The bus uses the wider silver conductor found in the Solar Cells kit. We also recommend that you remove the “middle” point; with its help, two additional shunt diodes are installed.
	The terminal is also installed with outside frames
	This is what the diagram of connecting elements looks like without a displayed midpoint.
	This is what the terminal strip looks like with the “middle” point displayed. The “middle” point allows you to install a shunt diode on each half of the battery, which will prevent the battery from discharging when the lighting decreases or one half is darkened.
	The photo shows a bypass diode on the "positive" output, it resists the discharge of batteries through the battery at night and the discharge of other batteries during partial darkness. Most often, Schottke diodes are used as shunt diodes. They provide less loss in the total power of the electrical circuit. An acoustic cable in silicone insulation can be used as current carrying wires. For isolation, you can use tubes from under the drip. All wires must be firmly fixed with silicone.
	The elements can be connected in series (see photo), and not through a common bus, then the 2nd and 4th rows must be rotated 1800 relative to the 1st row.

The main problems in assembling a solar panel are related to the quality of soldering contacts, so experts suggest testing it before sealing the panel.

Panel testing before sealing, mains voltage 14 volts, peak power 65 W

Testing can be done after soldering each group of elements. If you pay attention to the photos in the master class, then the part of the table under the solar elements is cut out. This was done intentionally to determine the functionality of the electrical network after soldering the contacts.

Sealing the solar panel

Sealing solar panels when making them yourself is the most controversial issue among experts. On the one hand, sealing panels is necessary to increase durability; it is always used in industrial production. For sealing, foreign experts recommend using the epoxy compound “Sylgard 184”, which gives a transparent polymerized highly elastic surface. The cost of “Sylgard 184” on eBay is about $40.

Sealant with high degree elasticity "Sylgard 184"

On the other hand, if you do not want to incur additional costs, it is quite possible to use silicone sealant. However, in this case, you should not completely fill the elements to avoid them possible damage during operation. In this case, the elements can be attached to the back panel using silicone and only the edges of the structure can be sealed. It is difficult to say how effective such sealing is, but we do not recommend using non-recommended waterproofing mastics; the probability of contacts and elements breaking is very high.

	Before starting sealing, it is necessary to prepare the Sylgard 184 mixture.
	First, the joints of the elements are filled. The mixture must set to secure the elements to the glass.
	After fixing the elements, a continuous polymerizing layer of elastic sealant is made; it can be distributed using a brush.
	This is what the surface looks like after applying the sealant. The sealing layer must dry. After complete drying, you can cover the solar panel with the back panel.
	This is what the front side of a homemade solar panel looks like after sealing.

House power supply diagram

Home power supply systems using solar panels are usually called photovoltaic systems, that is, systems that generate energy using the photoelectric effect. For individual residential buildings, three photovoltaic systems are considered: an autonomous energy supply system, a hybrid battery-grid photovoltaic system, a battery-less photovoltaic system connected to central system energy supply.

Each of the systems has its own purpose and advantages, but most often in residential buildings use photovoltaic systems with backup rechargeable batteries and connection to a centralized power grid. The power grid is powered using solar panels, in the dark from batteries, and when they are discharged - from the central power grid. In remote areas where there is no central network, liquid fuel generators are used as a backup source of energy supply.

A more economical alternative to a hybrid battery-grid power system would be a batteryless solar system connected to the central grid. Electricity is supplied from solar panels, and at night the network is powered from the central network. Such a network is more applicable for institutions, because in residential buildings most of the energy is consumed in the evening.

Diagrams of three types of photovoltaic systems

Let's consider typical installation battery-grid photovoltaic system. Solar panels, which are connected through a junction box, act as an electricity generator. Next, a controller is installed on the network solar charge to avoid short circuit at peak load. Electricity is accumulated in backup batteries and is also supplied through an inverter to consumers: lighting, household appliances, electric stove, and possibly used to heat water. To install a heating system, it is more effective to use solar collectors, which belong to alternative solar technology.

Hybrid battery-grid photovoltaic system with alternating current

There are two types of power grids used in photovoltaic systems: DC and AC. The use of an alternating current network allows you to place electrical consumers at a distance exceeding 10-15 m, as well as provide a conditionally unlimited network load.

For a private residential building, the following components of a photovoltaic system are usually used:

• the total power of solar panels should be 1000 W, they will provide a generation of about 5 kWh;
• batteries with a total capacity of 800 A/h at a voltage of 12 V;
• the inverter must have a rated power of 3 kW with a peak load of up to 6 kW, input voltage 24-48 V;
• solar discharge controller 40-50 A at a voltage of 24 V;
• source uninterruptible power supply to provide a short-term charge with a current of up to 150 A.

Thus, for a photovoltaic power supply system you will need 15 panels with 36 elements, an example of assembly of which is given in the master class. Each panel provides a total power of 65 watts. Solar batteries based on monocrystals will be more powerful. For example, a solar panel of 40 monocrystals has a peak power of 160 W, but such panels are sensitive to cloudy weather. In this case, solar panels based on polycrystalline modules are optimal for use in the northern part of Russia.

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 received energy, 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 point it at the surface Sun rays, then a tiny electric current can be determined by 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 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, and to use household appliances and appliances you need alternating current and voltage 220 volts. 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. 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. Charge controller in simple design It’s not that expensive, so there’s not much 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 housing hermetically sealed - direct exposure of photovoltaic cells to atmospheric precipitation 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, 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:

1. Measure out desired length tires and cut into pieces the required number of strips.
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 droplets 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 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 combining different types of 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. When installing, you need to take into account external factors. 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. 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.
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.