DIY solar power source. Solar energy in your home: how to make a battery with your own hands

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

Arguing with friends about payback was ridiculous…. When buying a car, no one thinks about payback. Auto as a mistress, prepare the amount for pleasure in advance. And here it’s quite the opposite, I spent money so they are also trying to pay off ... In addition, I connected an incubator to solar panels so they still justify their purpose, protecting your future economy from death. In general, having an incubator, you depend on many factors, here it’s either pan or layman. When I have time, I will write about a homemade incubator. Well, why argue, everyone has the right to choose ... ..!

After a long wait, the cherished box with thin fragile plates finally warms the 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 helpful. And then disappointment set in ..... As it turned out, five people made the panels with their own hands, the rest were simply copied to their sites, and some, in order to be more original, were copied from different developments. Well, God bless them, let it remain on the conscience of the owners of the pages.

I decided to read the forums, the long arguments of the theorists "how to milk a cow" led to complete discouragement. Reasoning about how the plates break from heating, sealing difficulties, etc. I read 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?

We set the task:

1) The panel must be made from improvised materials, so as not to pull the wallet, because the result is unknown.

2) The manufacturing process should be easy.

We start manufacturing a solar panel:

First of all, 2 glasses 86x66 cm were purchased for the future two panels.

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

A long search for aluminum corners, according to the experience already tested by "colleagues", ended in nothing.

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

I will not describe the process of soldering panels, since there is a lot of information about this on the network 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 solder POS-40 is quite suitable, in any case, I did not experience any difficulties. And of course, our native rosin, where without it ... During the soldering, I did not break a single element, I think you 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 tin-plated, which significantly reduces soldering time. Although it is quite possible to use a regular wire, I conducted an experiment on spare plates, I did not experience any difficulties in soldering. (pictured is the 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 desirable to use a soldering iron at 40 watts. Since the plates easily remove heat, and this makes soldering difficult. The first attempts to solder 25 with a cotton soldering iron were tedious and sad.

Also, when soldering, it is desirable to optimally select the amount of flux (rosin). For a large excess of it does not allow the tin to stick to the plate. And therefore it was necessary to practically tin the plate, in general, it's okay, everything is fixable. (Look at the photo you can see.)

Tin consumption is quite large.

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

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

tapes that I used.

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

Well, glued plates with adhesive tape and a fixed jamb.

Next, remove the protective layer of double-sided tape from the panel edging and glue a plastic film on it with a margin for the edges. (I forgot to take a picture) Oh, yes, we make slots in the adhesive tape for outgoing wires. Well, not stupid, you will understand what and when ... Along the edge of the glass, as well as wire leads, corners, we coat with silicone sealants.

And we bend the film to the outside.

The frame was made of plastic. When I installed plastic windows in the house, a plastic profile for the window sill is attached to the window with screws. I thought this part was too thin. Therefore, he removed and made the window sill in his own way. Therefore, plastic profiles remained from 12 windows. That is to say, the material is in abundance.

I glued the frame with an ordinary, old, Soviet iron. It’s a pity I didn’t film the process, but I think there’s nothing beyond incomprehensible here. I cut off 2 sides at 45 degrees, heated it on the sole of the iron and glued it after setting it at an even angle. In the photo there is a frame for the second panel.

We install glass with elements and a protective film in the frame

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

We get such a panel.

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

Well, let's start testing.

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

Unfortunately didn't take a picture. It must be said that the current strength depends sharply on the illumination.

Now 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 even cheered. After all, these are the most average conditions for a battery, which means the result is more plausible than in bright sunlight. The sun shone through the clouds not so brightly. I must say that the sun was shining a little from the side.

With such lighting, the short-circuit current was 7.12 Amperes. What I consider to be an excellent result.

Voltage without load 20.6 volts. Well, it's stable around 21 volts.

The battery charge current is 2.78 Amps. That under such lighting guarantees a battery charge.

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

By that time, the weather was getting worse, the clouds were closed, the sun was full and I was wondering what it would show in this situation. It's almost evening twilight...

The sky looked like this, specially removed the horizon line. Yes, by the way, on the glass of the battery you can see the sky as in a mirror.

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

Short circuit current 2.48A. In general, then, for such lighting is wonderful! Almost equal to one battery in good sun.

The battery charge current is 1.85 Amperes. What can I say ... Even at dusk, the battery will be charged.

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

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

I want to say the same about controllers. All this looks nice, but not worth the money spent on the controller.

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

Well, the wind came up and the remaining spare 5 elements fell into an uncontrolled flight ... .. the result was fragments. Well, what to do, carelessness should be punished. And on the other hand…. Where are they?

We decided to make another socket out of the fragments, 5 volts. It took 2 hours to make. The rest of the materials just came at the right time. Here's what happened.

The measurements were taken in the evening.

I must say that with 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, in the manufacture, select elements according to the area of ​​\u200b\u200blighting.

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. Such an orientation was not chosen by chance, because it was noticed that in this latitude, in summer, the sun rises at 4 am and by 6-7 o'clock quite tolerably charges the batteries with a current of 5-6 amperes, and also applies to the evening. Each panel must have its own diode. In order to exclude burnout of elements with different power panels. And as a result, an unjustified decrease in the power of the panels.
The descent from a height was made with a stranded wire with a cross section of 6mm2 each core. Thus, it was possible to achieve minimal losses in the wires.

Old barely-living batteries 150A.h, 75A.h, 55A.h, 60A.h. 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 100 Ah.
There is no battery charge controller. Although I think the installation of the controller is necessary. I am currently working on the controller circuit. Since during the day the batteries begin to boil. Therefore, you have to dump excess energy daily by turning on an unnecessary load. In my case, I turn on the lighting of the bath. 100 W. Also, during the day, an LCD TV of about 105W, a 40W fan, and an energy-saving light bulb of 20W are added in the evening.

I will say to those who like to carry out calculations: THEORY AND PRACTICE are not the same thing. Since such a "sandwich" works quite well for more than 12 hours. at the same time, we sometimes charge phones from it. I have not yet reached a full discharge of batteries. Which, accordingly, crosses out the calculations.

A computer uninterruptible power supply (inverter) 600VA, which approximately corresponds to a load of 300W, was used as a converter.
I also want to note that the batteries are charged even with a bright moon. At the same time, the current is 0.5-1 Ampere, I think this is not bad at all for the night.

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!

The comfort of living in the houses and apartments of a modern person over the years requires an increasing amount of electricity. But in modern conditions, the cost of each unit of electricity is steadily increasing, which, accordingly, affects the costs. Therefore, the issue of switching to alternative sources of electricity is the most relevant. One of the ways to ensure independence in obtaining electricity is the ability to use solar panels for this purpose for the home.

An effective alternative or a general misconception?

Talks about autonomous power supply of household appliances and lighting in houses using solar energy have been going on 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 the home will be a fairly effective way to replace traditional energy networks could be considered indisputable, if not for a couple of significant “buts”.

The main requirement for the efficiency of using helium batteries is the amount of solar energy. The device of the 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 sufficiently large areas to mount autonomous solar panels. If the batteries are planned to be placed in a summer cottage, a country house, a cottage, then there will be no problems here, but those living in apartment buildings will have to think about this seriously.

Solar battery - what is it?

The device of the solar battery is based on the ability of solar cells to convert solar energy into electricity. Connected into a 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 higher the given field, the higher the power of such a device. That is, the more solar cells it has, the more electricity it can produce.

But this does not mean that only huge areas where solar panels can be installed can provide the necessary electricity. There are many gadgets that have the ability to work not only from the usual autonomous power sources - batteries, accumulators - but also use solar energy. Portable solar panels are built into the design of such devices, which make it possible to both recharge the device and work autonomously. For example, an ordinary pocket calculator: in sunny weather, putting it on the table, you can recharge the battery, which prolongs its life for many years. There are many different devices where such batteries are used: these are pen-flashlights, and flashlights-key rings, etc.

In summer cottages and suburban areas, it has recently become fashionable to use solar-powered lanterns for lighting. The economical and uncomplicated device provides lighting along garden paths, on terraces and in all necessary places, using electricity stored 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, as well as utility rooms.

Types of autonomous solar panels

There are two types of solar energy converters, due to 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 polymers. Such batteries are installed in any available place, but have several disadvantages: they need a lot of space, low efficiency, and even with average cloud cover, 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 in which silicon converters are integrated, connected in a common circuit and filled with silicone. Easy to operate, high efficiency (up to 22%), waterproof, light and flexible, but require direct sunlight to work effectively. Cloudy weather can cause a complete cessation of electricity generation.

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

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, and are much more effective on cloudy days.

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

General principle for the selection and layout of parts for solar panels

Due to the latest requirements for the production of electrical energy, which are aimed at switching from the traditional raw materials used in its production, the topic of solar power sources is becoming more and more practical. Mass production of elements for creating their own electrical network already offers the consumer various options for providing autonomous electricity. But for the time being, the cost of an autonomous solar power source is 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, it is simply necessary to decide on the method of assembling such a device. Or, acquiring individual elements, assemble them yourself, or make all the components with your own hands.

What, in fact, consists of a power system based on the conversion of solar energy into electric current? The main, but not the last of its elements, is a 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 batteries with electric current received in solar panels. The next part of a home solar power plant is a battery of electric batteries, in which electricity is accumulated. And the last element of the "solar" electrical circuit will be an inverter that allows the resulting low voltage electricity to be used for household appliances rated at 220 V.

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

Now with regard to 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 the complete provision of housing needs. The difficulty lies in the correct calculation of the required power and the appropriate selection of components.

Starting to assemble the solar panel

Now you can find a lot of suggestions 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 you need to get, and decide at what voltage the network will operate. There are two options for solar networks - with direct current and alternating current. Alternating current is more preferable because of the possibility of distributing electricity consumers over a considerable distance - more than 15 meters. This is just right for a small house. Without going deep into calculations and starting from the experience of those who already use solar energy in their dachas, we can say with confidence that at the latitudes of Moscow - and going south, these figures will naturally be higher - one square meter of solar panels can produce up to 120 watts per hour. This is if polycrystalline elements are used during assembly. They are more attractive in price. And it is quite realistic to determine the total power by adding up the entire power consumption of each individual electrical appliance. It can be said very approximately 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 a description of solar networks using panels of 36 elements. Each of the panels has a power of about 65 watts. A solar battery for a dacha or a small private house can consist of 15 such panels that are capable of generating up to 5 kW per hour of total electrical power, having an 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 converting plates, the number of which depends on the power of a home-made solar power plant. For one battery, you will need 36 pieces. You can use the Solar Cells kit, as well as 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. You need to solder them taking into account the expansion - leaving a gap of up to five millimeters between them. Do-it-yourself solar battery installation requires utmost 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 60W 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 should be noted that the plates are very fragile, and it is desirable 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 during dimming or low light. To do this, the busbars of the panel halves are brought to the terminal block, creating a midpoint. These diodes also prevent the batteries from discharging at night.

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

Then it is worth deciding on the surface on which these plates will be attached. Rather, with the material for its manufacture. The most suitable in terms of characteristics and easily accessible is glass, which has the maximum light transmission capacity compared to plexiglass or carbonate.

The next step is to make the box. For this, an aluminum corner or a wooden beam is used. Glass is planted in the frame on the sealant - it is desirable 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 mounting method may be different, but solar panels for the home, reviews of which are common, were fixed mainly with a 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 fixed mainly on a drop in the middle of each element.

For the substrate, a different material is used, which is also attached to the sealant. It can also be chipboard of small thickness or a fiberboard sheet. Although you can, again, fill it with epoxy. The battery case must be sealed. A do-it-yourself solar battery made in this way, the assembly scheme of which was discussed above, will give 18-19 Volts, charging 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 solar cells for converting solar energy into electrical energy and independently. For this, silicon diodes are used, or rather their crystals, released from the cases. This process is laborious, and to start it or not, everyone decides for himself. 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 sunlight hits it, becomes exactly like a photographic plate. But getting to it and not damaging it is a rather complicated 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 scheme 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 in order to make a full-fledged solar battery for giving, you need to try very hard. Huge work, large areas, bulky design makes this occupation unpromising. But for small appliances and gadgets, this is quite a suitable design that anyone who loves to do electrical engineering can do.

Can LEDs be used for solar panels?

The LED solar panel is pure fiction. It is almost impossible to assemble even a small solar micropanel from LEDs. Or rather, you can create, but is it worth it? With the help of sunlight, it is quite possible to get about 1.5 volts of voltage on the LED, but the strength of the generated current is very small, and only a very strong sun is required to generate it. And yet - when a voltage is applied to it, the LED itself emits radiant energy, that is, it glows. This means that those of his brothers, who received sunlight of greater strength, 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 sense.

We heat the house with solar energy

If the real opportunity to provide household electrical appliances with "solar" current has already been mentioned above, then there are two options for heating housing with solar energy. And in order to use solar panels for home heating, you need to know some of the requirements that are required to complete this task.

In the first option, the use of solar energy for heating occurs using a system other than the usual electrical network. A device for heating a house using 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 glass tubes of small diameter, in which a liquid with a very low heating threshold is placed. When heated, this liquid further transfers its heat to water in a storage tank with a volume of at least 300 liters of water. Then this heated water is fed to heating panels made of thin copper pipes, which, in turn, give off the received 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 it will be necessary to agree that heating the water in the boiler with the help of heating elements will require the lion's share of the energy generated by the batteries. Simple calculations show that it takes about 4 hours to heat 100 liters of water to 70-80 ⁰С with a boiler. During this time, a water boiler with 2 kW heaters will consume about 8 kW. If solar panels in total capacity can generate up to 5 kW per hour, 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 will not be suitable for the full provision of electrical energy.

The use of a vacuum manifold for heating a house is justified when it is a full-fledged residential building. The scheme of operation of such a solar system provides heat to the entire dwelling 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 with a current of at least 800 A / h in the circuit, equipment for converting voltage from low to high - inverters, as well as voltage controllers for 24 V with a working current of up to 50 Amperes and a simple "uninterruptible" with a current of up to 150 Amperes, then you get a very decent power plant that runs on sunlight, which is able to provide the electricity needs of residents of a private house. Naturally, under certain weather conditions.

For a long time, solar panels were either bulky panels of satellites and space stations, or low-power photocells in pocket calculators. This was due to the primitiveness of the first single-crystal silicon photocells: they not only had a low efficiency (no more than 25% in theory, in practice - about 7%), but also noticeably lost efficiency when the angle of incidence of light deviated from 90˚. Taking into account that in Europe in cloudy weather the specific power of solar radiation can fall below 100 W/m 2 , too large areas of solar panels were required to obtain any significant power. Therefore, the first solar power plants were built only in conditions of maximum luminous flux and clear weather, that is, in deserts near the equator.

A significant breakthrough in the creation of solar cells has returned interest in solar energy: for example, the cheapest and most accessible polycrystalline silicon cells, although they have a lower efficiency than monocrystalline ones, are less sensitive to operating conditions. A solar panel based on polycrystalline wafers will give out enough stable voltage under partly cloudy conditions. More modern photovoltaic cells based on gallium arsenide have an efficiency of up to 40%, but are too expensive to make a solar battery with your own hands.

The video is a story about the idea of ​​​​building a solar battery and its implementation

Is it worth doing?