How to make a solar battery: 5 best master classes

A little theory

The main material for the production of panels is silicon, with the addition of boron and phosphorus. They are located on different sides of each other. Under the influence of sunlight, free electrons are separated from phosphorus (n-type side) and begin to move towards the boron plate. The boron plate, having free elements, or peculiar holes (p-type side), accepts free electrons. Or a p–n junction appears. Now all that remains is to remove this movement of electrons from the plate in the form of electric current.

Design and principle of operation

There are two main ways to use solar energy:

• Direct use for heating water and storing heat in solar heating and hot water supply systems.
• Converting light into electricity.

Reference. The basic laws of converting light into electricity were formulated at the end of the 19th century by the Russian scientist Alexander Stoletov.

The first solar panels appeared in the seventies of the last century, but imperfect technologies and low efficiency made the production of batteries expensive and low-profit. And only recent developments in this area have made the production of solar electricity technically and economically accessible.

There are several types of panels using different materials. But they are all built on semiconductors. The conversion of light is based on the internal photoelectric effect of the pn junction - the appearance of additional “holes” and free electrons under the influence of light. Electrons “rush” to the n-region, holes to the p-region. As a result of charge redistribution between regions, a potential difference arises and current flows through the junction.

Each module of a factory solar battery has its own supporting frame with a terminal box located on it.

This makes it possible to combine modules into a single system, with connection to common equipment, which allows you to control operation, accumulate electricity, convert it and distribute it among consumers. And to protect the photocells, a special coating of tempered glass is used.

Stationary solar panels are additionally equipped with inverters that convert direct current into alternating current. Compact modules do not require an inverter to power battery-powered devices. A similar compact module can be made with your own hands from diodes or transistors and connected to an “intermediate” battery. And from it you can charge a mobile phone (like from a Power Box) or use it to power an LED lamp.

The feasibility of a homemade solar panel

Understanding these physical properties of silicon will help you assemble your own solar panel. To begin work, you need to prepare.

In any case, a backup source of electricity is always in demand. Moreover, the cost of solar kilowatt is significantly lower than traditional electricity. Of course, many people want to purchase and install factory solar panels. The price for the entire set of equipment for a home power plant is daunting. Therefore, the question is very relevant: how to assemble a solar battery yourself?

A more competent approach is to calculate the amount of energy generated by one module:

W = k*Pw*E/1000

Where:

• E is the amount of solar insolation over a known period of time;
• k is the coefficient forming in summer - 0.5, in winter - 0.7;
• Pw is the power of one device.

Based on the planned total power consumption and calculated data, the total power consumption of electricity is calculated.

Now, if we divide the total by the expected performance of one photocell, we finally get the required number of modules.

Battery size calculation

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

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

Required tools and materials

If you are not intimidated by the volume and complexity of the work ahead, you need to thoroughly prepare.

The main element is the plates themselves. The number of elements is selected based on the output parameters of the future panel. But the main condition is that their technical characteristics must be identical to each other. And if there is no experience in assembling such structures, it would be better to take several elements in reserve, taking into account defects in the first stages of work.

We continue to collect materials:

• chipboard;
• metal profile and corner (preferably made of aluminum);
• foam rubber 1.6–2.7 cm high;
• base for plates made of transparent material;
• a set of self-tapping screws;
• several tubes of silicone sealant;
• wiring;
• terminal clamps.

We do not indicate the volume of raw materials because it is directly dependent on the dimensions and number of parts from which the homemade solar battery will be assembled.

Now the tool and auxiliary materials:

• screwdriver;
• hacksaw for metal and hacksaw for wood;
• 40 watt electric soldering iron;
• electrical tester;
• flux and solder for soldering;
• industrial alcohol, for treating surfaces for soldering;
• cotton pads-tampons.

Panel selection advice

To get an output power of 145 W at a voltage of 18 V and not go too far out of your budget, it is better to take a closer look at class B kits.

Class B kits account for the main share of the entire solar battery market. For those who want to try to assemble panels with their own hands, it is better to take a closer look at these manufacturers. But there are currently a lot of such companies and, as a rule, they are not engaged in production, but in the resale of finished components. Or, in order to save money, they actively use manual assembly of panels, which naturally leads to a decrease in quality. Therefore, you need to be prepared for the fact that the declared characteristics may not coincide with the actual parameters. And you shouldn’t count on warranty obligations from such little-known companies either.

If you purchase 36 pieces of Chinese panels on the Alibaba website, it will cost 3,200 rubles. With the price of a ready-made kit with the same characteristics being 6,250 rubles, the benefit is quite tangible.

Consequently, the idea of ​​making solar panels for your home with your own hands becomes even more relevant.

Which panels to buy

All products of this class are divided into:

1. Monocrystalline (more expensive).
2. Polycrystalline (amorphous).

The first ones have a more uniform structure, which is why the efficiency is much higher than that of amorphous ones. Actually, this is what causes the price increase.

It is very easy to distinguish these photocells from each other, both by color (dark blue monocrystal) and shape.

What to choose is up to the buyer to decide, but you should know that cheaper amorphous cells are made in small Chinese enterprises with deviations in the quality of materials, but at a lower cost.

To calculate the number of photocells, you need to focus on the projected output data of homemade panels.

According to the passport data, 0.12 kW/hour of electricity is removed from one square meter of panels. For domestic needs, it is enough to receive 280–320 kW per month from the device.

All elements must be the same size and denomination.

If you purchase a photocell with a protective wax coating, it must be removed after purchase.

Sequence of actions for preparing photocells:

1. Unpack the panels.
2. Treat with hot (90±5 degrees Celsius) water.
3. After the wax has melted, separate all the elements from each other.
4. Clean each panel of wax residue with hot water.
5. Lay the treated panels on a soft cloth and dry.

What is a solar battery and how does it work?

General concepts about the principle of generating electricity from solar energy

People who decide to assemble a solar battery have many questions, and for many this task seems completely impossible due to the apparent complexity of its design. However, in reality there are no particular difficulties in assembling it. And you can be convinced of this by studying the diagram and examining how a master who has made more than one similar device performs the work.

A solar battery is a set of photovoltaic converters of solar energy into electrical energy.

A solar battery is a set of photocells correctly connected to each other. Each of them has low generating abilities, but together they produce very decent indicators of generated power.

Individual photocells are connected into a single panel and protected on both sides by materials that are resistant to ultraviolet radiation, moisture and other atmospheric conditions. This is important, since batteries are most often used in an open, unprotected space - this could be the roof of a building, a balcony railing, or a clearing near a house.

The general design of the system for obtaining electrical energy from the solar system consists of a number of instruments and devices connected into a single circuit:

Approximate diagram of a system for generating consumer electrical energy from solar

• Converter wafers are semiconductor photovoltaic cells that have the ability to generate direct current when exposed to light. The plates are connected to each other according to a certain pattern using special busbars (flat conductors), and are assembled into a battery in a common housing.
• Battery panels assembled from photocells are connected to a controller with selected current and voltage parameters necessary to charge the battery.
• A battery or a whole battery of such batteries accumulates charge.
• A special inverter converts direct current into alternating current with a voltage of 220 V (if necessary).

Expert opinion: Afanasyev E.V.

Chief editor of the Stroyday.ru project. Engineer.

Such a series of devices is used in the scheme when it is planned to power individual permanent points of consumption or even completely power the entire house from solar energy. The energy accumulated in the battery during the day can be used on cloudy days or at night. Simpler schemes are also used, when solar panels act only as an auxiliary power source, and energy storage is not required. In this case, the panel can be directly connected to the consumer device. However, this option is less reliable, since the stability of the power supply will completely depend on the availability of the sun at the moment.

The use of solar panels to fully supply a home with energy is relevant in regions where the number of sunny days throughout the year prevails. The southern regions of the country are usually famous for this. In other conditions, they are most often used as additional sources of power supply.

Three main types of photovoltaic modules

The solar modules from which the panel is assembled are divided into three types:

— monocrystalline;

- polycrystalline;

- amorphous (thin film).

The efficiency of the design, as well as its overall cost, directly depends on the structural features of the plates.

Monocrystalline and polycrystalline solar battery options

Monocrystalline wafers are made from single crystals of silicon grown using the Czochralski method. They are of high quality and have a good (by the standards of photocells) efficiency of approximately 20÷22%. Because of this, their cost is quite high.

The sun's rays, falling on a monocrystalline surface, contribute to the occurrence of directed movement of free electrons. The plates on both sides are connected to busbars, which are then connected to the general electrical circuit of the system.

The high efficiency of this type of plate is explained by the fact that the sun's rays are evenly scattered over the surface of the crystal.

Polycrystalline solar cells are made from a semiconductor having a polycrystalline structure. This type of battery is considered optimal for creating a solar energy conversion system. The cost of the elements, and as a result, of entire batteries, is lower compared to monocrystalline devices. This is due to the peculiarities of the production of solar cells, since their production uses fragments left over from single crystals.

If we compare these two types of products, we can highlight the following differences, identified by testing of independent companies:

• Polycrystalline plates differ in appearance from single crystals, as they have a non-uniform surface color, with alternating dark and light areas.

The external difference between single crystal plates and polycrystal plates is the uniformity of color.

• During operation, all photocells experience a gradual decrease in power. So, after a year of operation, it decreases by 3% for single crystals, and by 2% for polycrystalline elements.
• The total amount of electricity generated by a monocrystalline module is approximately 30% higher than that of polycrystalline elements, given the same area.
• The cost of polycrystalline batteries is 10–15% lower than monocrystalline batteries.

Amorphous solar modules

This type of element is a dense flexible film that greatly simplifies the battery installation process.

There are three generations of similar photocells on the modern market:

Flexible film photocells based on amorphous silicon have a number of advantages and are much more convenient to use

• The first generation elements are single-junction. They have low efficiency - only 5% and a relatively short service life - no more than 10 years.
• The second generation film is also of the single-junction type, but its efficiency level has been increased to 8% and its service life has also been increased.
• Third-generation thin-film batteries have an efficiency of up to 12% and have a long service life, competing with crystalline options.

Despite their not outstanding characteristics, second-generation single-junction thin-film modules remain the most popular. They are affordable and have decent power that can easily compete with crystalline battery options.

Comparison of solar photovoltaic cells

If we compare crystalline and film batteries, the latter have a number of significant advantages, due to which they are often preferred:

• Amorphous film elements respond better to temperature changes, in particular to its increase. In the sunny months of the year, this type of battery is capable of producing more energy compared to its crystalline counterparts, which can lose up to 20% of their power when heated.
• Film batteries continue to generate energy even in diffuse sunlight, unlike crystal batteries, which do not generate energy in cloudy weather. In weak or diffuse light, an amorphous film is capable of generating up to 20% of its rated energy. Not too much, but better than nothing.
• The cost of crystalline panels is much higher than film panels. Moreover, the price of the latter continues to decline due to the active increase in their production volumes.
• Film solar cells have fewer defects and vulnerabilities. The fact is that the rigid plates are soldered together when forming the panel, and the film is installed in the body of the structure as a whole.

If we summarize the results and display them in a table, then the comparative characteristics of amorphous film and rigid crystalline solar solar cells will look like this:

It is necessary to clarify that combined versions of solar batteries are also produced, that is, consisting of crystalline and amorphous elements. That is, all the advantages of both types are used to the maximum. However, the cost of such products is very high, so they are not as popular as the batteries mentioned above.

What affects the efficiency of solar panels?

In order not to be surprised that solar panels operate with different efficiencies in different periods, it is necessary to highlight the factors that affect the efficiency of the system. Moreover, the moments mentioned below affect solar batteries of all types, but with different intensities.

• As the temperature rises, the performance of any panel photocells decreases.
• In case of partial dimming, for example, if the sun hits only part of the panel and a certain number of elements remain unlit, the output voltage drops due to the losses of the unlit plates.
• Panels equipped with lenses to concentrate radiation become completely ineffective in cloudy weather, since the effect of focusing the light flow disappears.
• To achieve high efficiency of a solar battery, the correct selection of load resistance is necessary. Therefore, the panels are not connected directly to the devices or battery, but through a controller that controls the system, which will ensure optimal battery operation.

Disadvantages of solar panels

Solar panels have a number of disadvantages, upon learning of which many homeowners immediately abandon the idea of ​​purchasing and installing them.

A truly powerful, efficient solar battery will require a considerable area completely exposed to sunlight.

• To obtain a sufficient amount of energy, it is necessary to install a very large number of batteries of quite large sizes. It is clear that large areas will be required to accommodate them. Many owners of private houses use the sunny side of the roof for their installation.

The total capacity of the battery pack must correspond to the power of the solar panels, so the number and type of battery must be selected correctly.

• We must not forget that the battery will work effectively only if its front side is periodically cleaned of accumulated dust, dirt, and dried rainwater stains. This means that it is necessary to provide convenient and easy access to the surface.
• Solar panels do not function effectively enough at dusk and do not work at all at night. To use energy from them at any time of the day, you need to connect to several batteries, which accumulate energy during the sunny period.
• For a large number of batteries, if the system is planned as the main source of energy, a separate room may be required.

The “storage” of the generated electrical energy can be a whole battery of batteries connected in a certain way. This will require a lot of space. And the cost of batteries can also be quite significant.

• Solar energy is considered environmentally friendly, but the solar cell plates themselves contain toxic substances such as cadmium, lead, arsenic, gallium, etc. When the structure is heated, these substances can be released not only into the environment, but also penetrate into the premises of the house if the batteries are installed on the roof or balcony of the house. The best option would be to install the system away from residential buildings.

Solar panels on a rotating mechanism that constantly maintains the surface in the focus of sunlight

• When installing batteries in an open area, for higher efficiency, the system is often equipped with a special photocell that responds to the position of the Sun, and a rotating mechanism that will rotate them following the movement of the luminary. Efficiency increases, but the complexity of the system and the cost of project implementation increase.
• So far there is no need to talk about the high efficiency of such systems. Their efficiency is, at best, 20%; the remaining 80% of solar energy received by the surface goes to heating the battery itself, the average temperature of which can reach 55–60 degrees. As mentioned above, when photocells heat up, their operating efficiency decreases.
• To prevent batteries from overheating, certain forced cooling systems are used. For example, fans or pumps are installed to pump refrigerant. It is clear that such devices also require electricity, as well as periodic maintenance. In addition, they can significantly reduce the reliability of the entire structure. Well, the problem of effective passive cooling of batteries has not yet been solved.

Frame making

A do-it-yourself solar battery begins its journey by making a frame from scrap materials.

The dimensions for it are calculated taking into account the parameters of the photocells themselves.

For the frame, you can use an aluminum corner with a shelf height of 70x90mm.

Why aluminum?

1. Structure weight. The entire structure will eventually weigh a lot, but this is a light and fairly strong metal.
2. Does not require anti-corrosion treatment.

To eliminate moisture ingress, all frame joints must be treated with silicone-based sealants.

Now that you have the metal frame, you can start making the solar panel housing.

Frame

Here the task is simpler - to make some kind of wooden box with low (2 cm) sides.

Before making a solar battery with your own hands, it would not hurt to prepare the materials. Here is a typical step-by-step instruction:

1. The base of the body is made from a single piece of chipboard. The sides are screwed with self-tapping screws to the chipboard sheet.

1. Drill holes in the wooden sides for ventilation.

1. Ventilation holes are also made on the chipboard sheet with a drill, in increments of 10 cm across the entire area of ​​the panel.

The base itself is ready. Now the solar panel assembly will continue with the installation of solar plates.

Video: making a solar panel with your own hands

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

Assembly of photocells

Before proceeding to this stage, it is necessary to study what the solar panel circuit looks like. Carefully arrange the elements on the base. It is important to maintain a distance between them of 3–5 mm. You can use crosses for installing tiles.

You need to prepare for soldering - bring out the contacts in order. Positive on one side, negative on the other.

The contacts on the panels may already be ready and fixed in place. If this is not the case, you will have to prepare and solder them yourself.

A homemade solar battery is made from crystalline elements. This is a rather fragile material, so you need to work with them with special care.

The manufacture of solar panels requires special treatment. To solder solar plates correctly without damaging them, you need to handle the parts carefully. Choose the right soldering iron with a permissible power of 24/36 W.

When all the plates are soldered, the circuit must be supplemented with self-discharge diodes (charge controller) and an acoustic cable at the output for connection.

Fix all panel elements with your own hands using sealant.

Now all the elements are selected and placed inside the frame.

Installation and connection of a solar battery to consumers

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

Solar battery frame drawing

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

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

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

Testing the battery before sealing

The work is nearing completion, but before further assembly of the panel with elements from China, it is necessary to check whether the assembled structure works at all?

There is a high probability of poor-quality soldering of contacts. As a matter of fact, it is better to do such a check after soldering each row of photocells - this will greatly simplify the detection of places of poor-quality connections.

Testing is carried out in an open area in sunny weather at noon, when the sun is not covered by clouds. A regular digital tester is suitable for measurements.

The prepared battery must be taken outside, pointed at the sun at the desired angle of inclination, which is calculated in advance. We switch the tester to current measurement mode and measure short circuit currents.

In theory, the panel current should be 0.5–1.0 A lower than the short circuit current. If the tester shows a current strength above 4.5 A, then the solar battery is assembled normally and is fully operational.

If the readings differ downward, you need to look for a weak soldered contact in the connection of the photocells.

Sealing

After the tests show the performance of all elements, the stage of sealing the photocells already placed in the frame begins. Epoxy glue is best suited for this purpose.

But its use will inevitably increase the cost of the entire “do-it-yourself panel” project. Although epoxy can be replaced with silicone sealant, not just any sealant, but one that is designed for use at subzero ambient temperatures.

Sealing can be done in different ways:

• fill in all the made elements immediately from edge to edge;
• The voids between the photocells and the edges of the frame are filled.

When working, you should consider some points:

• The surface must be perfectly flat. Otherwise, the elements will crawl to the side under their own weight.
• Hardening occurs faster at high ambient temperatures. All sealants have their own instructions.

If everything is taken into account and done correctly, the result will be a water-repellent and completely transparent surface. Let's assemble the panel further.

Cover fastening features:

1. After waterproofing the assembled battery, it can be closed with a lid and fixed. But this can be done only after the adhesive composition has completely dried. If you hurry and fasten the lid, the glue will evaporate and cloudy stripes will remain on the plexiglass.
2. Using the cable that now comes out of the panel, make a two-pin connector for the controller.
3. Battery performance is checked again.

Now the panel, assembled with your own hands at home, is ready for installation and its connection to the home solar system.

Advantages and disadvantages of natural energy

Why is natural energy so good and what pushes not only individuals, but also owners of large enterprises to install modules? The main advantages of solar converters are:

• availability of a source of electricity, which will cost the user free of charge;
• positive impact on environmental protection;
• durability of devices;
• simple installation and operating principle;
• no problems with rising utility prices.

However, among all the advantages, the panels have disadvantages such as:

• very high cost;
• purchasing an increased number of photocells to meet the needs of a large family or a room with an area of ​​more than 50 square meters. m;
• performance decline when the panel operates in cloudy weather.

Installation of a finished system

1. For full operation of solar panels, you need to additionally purchase a current inverter from 12 V to 200 V to convert direct current from the panel to alternating current.
2. In order not to overload the system and to save electricity, you need at least two gel or AGM batteries.
3. The system will not be complete without a controller that will control the operation of storage batteries.

The installation location is chosen before making the solar panel. It also plays a big role.

Solar panels can be placed on the ground, on walls or on the roof. It's a matter of taste and free space. But it is important that the panel receives maximum sunlight. Therefore, any falling shadow on the structure is extremely undesirable.

You can often see a system of similar Chinese panels on the roofs of houses. But in any case, you need to make sure that the roof itself is reliable and whether it can withstand the additional weight from solar cells. And this is an essential condition. Because in addition to the installation of the solar panels themselves, they will add the weight of the brackets and the rotating system, which cannot be avoided - the installation angle is strictly regulated. It should be 30–40 degrees to the roof.

If the panels are made of thin-film materials, you need to protect them from additional wind loads and pressure from accumulated snow. It needs reliable wind protection.

A good solution for a summer house is ground installation on a metal frame made of a reliable profile with a cross-section of 25x25 mm or larger. Wind breakers and snow protection must be installed in front of the frame structure.

Drafting

At the project preparation stage, it is necessary to determine the most suitable location for installing the solar panel. Determine which side of the site receives the most sunlight and does not receive shadows from trees and other buildings. The installation location can be on the ground, roof slopes, walls or free-standing structures. For example, if you want to install a solar panel on your roof, you need to make sure that the structure can support its weight.

Due to the fact that the maximum performance of mono- and polycrystalline cells is ensured only when the sun's rays hit them perpendicularly, it is desirable to assemble an adjustable design for them. Which will allow you to change the angle of the solar battery, depending on the time of year or even the time of day. Since the position of the light source at different periods of the year and day differ significantly (Figure 1).

Rice. 1: dependence of the position of the sun on the season

Also note that in a permanently installed battery, for example, generating 7 kW/h under ideal conditions, only 3 kW/h will be produced in the morning and evening. Accordingly, when installed in only one position, the battery will only provide rated power for a few months a year. If you decide to mount it in a stationary position, the panels should be placed at an angle of 50 to 60º; for adjustable ones, two limits are set - winter at 70º and summer at 30º, and in the intermediate period, they are tilted as stationary.

To determine the number of plates, it is necessary to calculate how much electric current or power one of them or 1 m2 generates. As a rule, 1 m2 produces about 125 W, so to get about 2.5 kW for domestic needs, you need to install 20 m2 of panels.

What affects the efficiency of solar panels?

Now it is clear that it is quite possible to assemble a solar battery with your own hands. But we must understand that the effectiveness of such an energy source depends on many factors. Moreover, this applies to devices of all types - both factory and homemade:

1. Photocells lose their performance as their temperature rises.
2. If part of the panel falls into the shade and the sun illuminates only part of the photocells, as a result there is a general drop in the output voltage.
3. If the panels are equipped with additional lenses to concentrate sunlight, then their effectiveness drops to zero in cloudy or cloudy weather. There is no sun and there is simply nothing to focus on.
4. The highest possible efficiency is possible with proper selection of load resistance. For this purpose, it is better to connect the photo panels yourself not directly to energy consumers or batteries, but through a special controller. With its help, the battery will work as efficiently as possible.

Do-it-yourself solar battery - how to make, assemble and manufacture?

Moving away from homemade options, we will pay attention to more serious things. Now we’ll talk about how to properly assemble and make a real solar battery with your own hands. Yes - this is also possible. And I want to assure you that it will be no worse than purchased analogues.

To begin with, it is worth saying that you probably will not be able to find on the open market the actual silicon panels that are used in full-fledged solar cells. Yes, and they will be expensive. We will assemble our solar battery from monocrystalline panels - a cheaper option, but showing excellent performance in terms of generating electrical energy. Moreover, monocrystalline panels are easy to find and are quite inexpensive. They come in different sizes. The most popular and popular option is 3x6 inches, which produces 0.5V equivalent. We will have enough of these. Depending on your finances, you can buy at least 100-200 of them, but today we will put together an option that is enough to power small batteries, light bulbs and other small electronic elements.

Selection of photocells

As we stated above, we chose a monocrystalline base. You can find it anywhere. The most popular place where it is sold in huge quantities is the Amazon or Ebay trading platforms.

The main thing to remember is that it is very easy to run into unscrupulous sellers there, so buy only from those people who have a fairly high rating. If the seller has a good rating, then you will be sure that your panels will reach you well packaged, not broken, and in the quantity you ordered.

Site selection (attitude system), design and materials

After you have received your package with the main solar cells, you must carefully choose the location for installing your solar panel. After all, you will need it to work at 100% power, right? Professionals in this matter advise installing it in a place where the solar battery will be directed just below the celestial zenith and look towards West-East. This will allow you to “catch” sunlight almost all day.

Making a solar battery frame

• First you need to make a solar panel base. It can be wooden, plastic or aluminum. Wood and plastic perform best. It should be large enough to fit all your solar cells in a row, but they won't have to hang around inside the entire structure.

• After you have assembled the base of the solar battery, you will need to drill many holes on its surface for the future output of conductors into a single system.

• By the way, do not forget that the entire base must be covered with plexiglass on top to protect your elements from weather conditions.

Soldering elements and connecting

Once your base is ready, you can place your elements on its surface. Place the photocells along the entire structure with the conductors down (you push them into our drilled holes).

Then they need to be soldered together. There are many schemes on the Internet for soldering photocells. The main thing is to connect them into a kind of unified system so that they can all collect the received energy and direct it to the capacitor.

The last step will be to solder the “output” wire, which will be connected to the capacitor and output the received energy into it.

Installation

This is the final step. Once you are sure that all the elements are assembled correctly, fit tightly and do not wobble, and are well covered with plexiglass, you can begin installation. In terms of installation, it is better to mount the solar battery on a solid base. A metal frame reinforced with construction screws is perfect. The solar panels will sit firmly on it, not wobble or succumb to any weather conditions.

That's all! What do we end up with? If you made a solar battery consisting of 30-50 photocells, then this will be quite enough to quickly charge your mobile phone or light a small household light bulb, i.e. What you end up with is a full-fledged homemade charger for charging a phone battery, an outdoor country lamp, or a small garden lantern. If you have made a solar panel, for example, with 100-200 photocells, then we can already talk about “powering” some household appliances, for example, a boiler for heating water. In any case, such a panel will be cheaper than purchased analogues and will save you money.

Solar battery made from old transistors

Those who repair radio equipment accumulate their strategic stock of radio parts over time. Among them may be transistors or diodes in a metal case. They are no longer suitable for repairing modern devices due to their large dimensions, but assembling a small photopanel from old transistors is quite possible.

It is best to find CT or P type transistors from available materials:

To get to the photocell, you need to carefully cut off its upper part. Beneath it is a silicon semiconductor element - a photocell. You can cut off the lid if you carefully hold the part in a vice with a hacksaw.

The plate is visible underneath. It is this that will be the main element in the future scheme.

There are three output contacts:

• base;
• emitter;
• collector.

We need a collector. It is he who has a good potential difference.

Assemble the initial chain according to the diagram:

All elements must be assembled on a flat surface made of dielectric material. Based on the parameters of the future photopanel, a sequential chain of parts is assembled. And then a parallel group of such chains is recruited.

If one transistor is capable of delivering 0.35 V and a current with a short circuit of 0.25 μA, then you can select the estimated number of chains from radio components based on these characteristics.

Do not forget that the assembled battery of LEDs will need cooling. Therefore, it is not recommended to place parts tightly and close to each other. This will make natural ventilation work better.

Experienced craftsmen know that this design is inconvenient due to its large dimensions. A DIY solar battery made from diodes is much more practical.

In any case, it makes sense to try to solder an alternative energy source for two reasons:

1. At a minimum, old radio components will be added.
2. It can power a digital clock or even a small radio.

Do-it-yourself solar battery from improvised means and materials at home

Despite the fact that we live in a modern and rapidly developing world, the purchase and installation of solar panels remains the lot of wealthy people. The cost of one panel that will produce only 100 Watts varies from 6 to 8 thousand rubles. This is not counting the fact that you will have to buy capacitors, batteries, a charge controller, a network inverter, a converter and other things separately. But if you don’t have a lot of money, but want to switch to an environmentally friendly source of energy, then we have good news for you - you can assemble a solar battery at home. And if you follow all the recommendations, its efficiency will be no worse than that of the version assembled on an industrial scale. In this part we will look at step-by-step assembly. We will also pay attention to the materials from which solar panels can be assembled.

From diodes

This is one of the most budget materials. If you are planning to make a solar battery for your home from diodes, then remember that these components are used to assemble only small solar panels that can power some minor gadgets. D223B diodes are best suited. These are Soviet-style diodes, which are good because they have a glass case, due to their size they have a high installation density and have a reasonable price.

After purchasing the diodes, clean them of paint - to do this, just place them in acetone for a couple of hours. After this time, it can be easily removed from them.

Then we will prepare the surface for the future placement of diodes. This can be a wooden plank or any other surface. It is necessary to make holes in it throughout its entire area. Between the holes it will be necessary to maintain a distance of 2 to 4 mm.

Then we take our diodes and insert them with aluminum tails into these holes. After this, the tails need to be bent in relation to each other and soldered so that when receiving solar energy they distribute electricity into one “system”.

Our primitive solar battery made of glass diodes is ready. At the output, it can provide energy of a couple of volts, which is a good indicator for a homemade assembly.

From transistors

This option will be more serious than the diode one, but it is still an example of harsh manual assembly.

In order to make a solar battery from transistors, you will first need the transistors themselves. Fortunately, they can be bought in almost any market or electronic stores.

After purchase, you will need to cut off the cover of the transistor. Hidden under the lid is the most important and necessary element - a semiconductor crystal.

Next, we prepare the frame of our solar battery. You can use both wood and plastic. Plastic, of course, will be better. We drill holes in it for the transistor leads.

Then we insert them into the frame and solder them together, observing the “input-output” standards.

At the output, such a battery can provide enough power to operate, for example, a calculator or a small diode light bulb. Again, such a solar battery is assembled purely for fun and does not represent a serious “power supply” element.

From aluminum cans

This option is already more serious, unlike the first two. This is also an incredibly cheap and effective way to get energy. The only thing is that at the output there will be much more of it than in the versions of diodes and transistors, and it will not be electrical, but thermal. All you need is a large number of aluminum cans and a housing. A wooden body works well. The front part of the housing must be covered with plexiglass. Without it, the battery will not work effectively.

Before starting assembly, you need to paint the aluminum cans with black paint. This will allow them to attract sunlight well.

Then, using tools, three holes are punched in the bottom of each jar. At the top, in turn, a star-shaped cutout is made. The free ends are bent outwards, which is necessary for improved turbulence of the heated air to occur.

After these manipulations, the cans are folded into longitudinal lines (pipes) into the body of our battery.

A layer of insulation (mineral wool) is then placed between the pipes and the walls/back wall. The collector is then covered with transparent cellular polycarbonate.

This completes the assembly process. The last step is to install the air fan as a motor for the energy carrier. Although such a battery does not generate electricity, it can effectively warm up a living space. Of course, this will not be a full-fledged radiator, but such a battery can warm up a small room - for example, an excellent option for a summer house. We talked about full-fledged bimetallic heating radiators in the article - which bimetallic heating radiators are better and stronger, in which we examined in detail the structure of such heating batteries, their technical characteristics and compared manufacturers. I advise you to read it.

Diode battery

A solar battery made from D223B diodes can really become a source of electric current. These diodes have the highest voltage and are housed in a glass case coated with paint. The output voltage of the finished product can be determined from the calculation that one diode in the sun generates 350 mV.

1. Place the required number of radio components in a container and fill it with acetone or another solvent and leave for several hours.
2. Then, you need to take a plate of the required size from a non-metallic material and make markings for soldering the components of the power source.
3. Once soaked, the paint can be easily scraped off.
4. Armed with a multimeter, in the sun or under a light bulb we determine the positive contact and bend it. The diodes are soldered vertically, since in this position the crystal best generates electricity from the sun's energy. Therefore, at the output we get the maximum voltage that the solar battery will generate.

Diode wiring

History of creation and prospects for use

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

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

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

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

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

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

Foil battery

In addition to the two methods described above, the power source can be assembled from foil. A homemade solar battery, made according to the step-by-step instructions described below, will be able to provide electricity, although of very low power:

1. For homemade products you will need copper foil with an area of ​​45 square meters. cm. The cut piece is treated in a soap solution to remove fat from the surface. It is also advisable to wash your hands so as not to leave grease stains.
2. Using sandpaper, it is necessary to remove the protective oxide film and any other type of corrosion from the cutting plane.
3. A sheet of foil is placed on the burner of an electric stove with a power of at least 1.1 kW and heated until red-orange spots form. With further heating, the resulting oxides are converted to copper oxide. This is evidenced by the black color of the surface of the piece.
4. Once the oxide has formed, heating must be continued for 30 minutes to form an oxide film of sufficient thickness.
5. The roasting stops and the sheet cools down along with the stove. When cooling slowly, the copper and oxide cool at different rates, making the latter easier to peel off.
6. Remaining oxide is removed under running water. In this case, you should not bend the sheet and mechanically tear off small pieces so as not to damage the thin layer of oxide.
7. A second sheet is cut to the size of the first.
8. Place two pieces of foil in a 2-5 liter plastic bottle with the neck cut off. Secure them with alligator clips. They must be positioned so that they do not connect.
9. A negative terminal is connected to the processed piece, and a positive terminal is connected to the second piece.
10. A saline solution is poured into the jar. Its level should be 2.5 cm below the top edge of the electrodes. To prepare the mixture, 2–4 tablespoons of salt (depending on the volume of the bottle) are dissolved in a small amount of water.

Foil battery

All solar panels are not suitable for providing a cottage or private home with electricity due to their low power. But they can serve as a power source for radios or charging small electrical appliances.

Which option should I choose?

The first thing you need is to purchase a photovoltaic inverter. Various models are offered by both domestic and foreign manufacturers. The cheapest options are Chinese silicon solar cells. They have a number of disadvantages, but, in comparison with American and domestic ones, they are much cheaper. All models, depending on the type, are divided into three types:

• monocrystalline modules - consist of artificially grown crystals of sufficiently large sizes. They are distinguished by the highest efficiency of 13 - 26% and the longest service life of 25 years. The disadvantage of solar batteries based on them is the decrease in maximum efficiency during the period of operation.
• polycrystalline solar cells - in comparison with the previous ones, have a much shorter service life, as the manufacturer claims - 10 years. They can also provide only 10 - 12% efficiency, in comparison with the previous ones, but this parameter remains constant for them throughout the entire period of operation.
• Amorphous batteries are film batteries in which amorphous silicon is applied to a flexible base. Such photocells appeared relatively recently and can be glued to any surface - windows, walls, etc. They are characterized by the lowest efficiency - 5 - 6%.

The choice of a specific type depends on your wishes and goals. For example, if the amount of solar radiation is relatively low in your region, it is better to install monocrystalline converters, since they have the highest efficiency.

Disadvantages of solar panels

Now that DIY panels have become even more affordable, not all homeowners are eager to acquire such an alternative source of electricity. And there are reasons for this:

• a powerful and efficient system requires a large area that will be completely open to direct sunlight;
• In order to cover all the needs for solar energy received, the solar system must be equipped with a sufficiently large number of panels. This leads to another problem - to accommodate a large number of photocells, large areas open to direct solar radiation are needed;
• for the normal functioning of the system, it is necessary to select batteries that will match the power of the solar system;

• Since the system is completely ineffective in the twilight and does not work at all at night, it is necessary to supplement it with batteries. They accumulate energy during the day and release it in the evening or at night;
• since there will most likely be not one battery for solar panels, but several, they need a separate room, which must also meet all safety standards;
• While the system is new, it will work at its maximum efficiency. But weather factors - dust, snow, rain - will inevitably reduce the efficiency of the system. This means that all elements need periodic cleaning, and for this there must be easy access to them;
• Today, the most efficient systems are those assembled from film photovoltaic cells made from thin polymers based on cadmium telluride. But the use of such expensive components in home-made home systems is absolutely not cost-effective.

Varieties

Solar batteries are divided into the following types.

Silicon

Silicon is the most popular battery material.

Silicon batteries are also divided into:

1. Monocrystalline: These batteries use very pure silicon.
2. Polycrystalline (cheaper than monocrystalline): polycrystals are obtained by gradually cooling silicon.

Film

Such batteries are divided into the following types:

1. Based on cadmium telluride (10% efficiency): cadmium has a high light absorption coefficient, which allows it to be used in the production of batteries.
2. Based on copper selenide - indium: efficiency is higher than the previous ones.
3. Polymer.

Solar batteries from polymers began to be manufactured relatively recently; usually furellenes, polyphenylene, etc. are used for this. Polymer films are very thin, about 100 nm. Despite the efficiency of 5%, polymer batteries have their advantages: low cost of material, environmental friendliness, elasticity.

Amorphous

The efficiency of amorphous batteries is 5%. Such panels are made from silane (hydrogen silicon) according to the principle of film batteries, so they can be classified as both silicon and film. Amorphous batteries are elastic, generate electricity even in bad weather, and absorb light better than other panels.

Disposal of the system

Solar systems assembled in production are designed for a 45-year service life. Their components - the controller and the inverter - last about 20 years. The battery life is also very limited, but certainly does not exceed ten years.

Therefore, a logical question arises: what to do with the elements of the solar system that have exhausted their service life?

The answer is obvious - sell!

There is no doubt that in your city there will be a company ready to buy these components.

They are quite suitable for reuse to create similar systems. The price of natural silicon is very high, as is its processing. It is more profitable to buy back used elements, recycle them and put them into re-production of solar panels. This is much more profitable than buying raw materials or mining rare earth materials yourself.

Where can I buy

You can purchase solar panels either in a specialized store or online in an online store. In the second case, the budget option for purchasing products on the Aliexpress website deserves special attention. For some panels there is an option for shipment from a warehouse in the Russian Federation; they can be received as quickly as possible; to do this, when ordering, select “Delivery from the Russian Federation”: