How to solder solar cells diagram. DIY solar power plant

Life in the "Organic" style, such a popular idea in recent years, presupposes a harmonious "relationship" between a person and the environment. The stumbling block of 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, which does not harm the environment, is the basis for many new energy technologies. One of these areas of 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 power supply systems in a country house.

At the moment, industrial power plants based on solar panels, used for 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 terms of the ratio of the guaranteed service life to the average annual cost of maintaining a country house is quite high: firstly, today the average cost of solar energy is commensurate with 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 power supply. In the first case, solar collector technology is used, in the second, the photovoltaic effect is used to generate electric current in solar panels. We want to talk about the possibility of self-manufacturing solar panels.

The technology for manually assembling a solar power system is quite simple and affordable. Almost every Russian can assemble individual power systems with high efficiency at relatively low costs. It is profitable, affordable and even fashionable.

Choosing 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 full-featured system, it can be built up gradually. If the first experiment was successful, then it makes sense to expand the functionality of the solar system.

At its core, a solar battery is a photovoltaic generator that converts solar energy into electrical energy. Light quanta hitting the silicon wafer knock out an electron from 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. For self-assembly of a solar battery, select 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 rather low efficiency (7-9%), but this drawback 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. The efficiency indicators of silicon crystals from different manufacturers can vary significantly. According to the practice of solar power plants in field conditions, we can talk about the service life of monocrystalline modules for more than 30 years, and for polycrystalline ones - more than 20 years. Moreover, over the entire period of operation, the power loss in silicon mono- and polycrystalline cells is no more than 10%, while in thin-film amorphous batteries in the first two years the power decreases by 10-40%.

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

A Solar Cells kit for assembling a solar array from 36 and 72 solar cells is available at ebay. Such kits are also available on sale in Russia. As a rule, B-type solar modules are used for self-assembly of solar panels, that is, modules rejected in industrial production. These modules do not lose their performance and are much cheaper. Some suppliers offer solar modules on a fiberglass board, which implies a high level of tightness of the elements, and, accordingly, reliability.

Development of a project for a helium energy system

The design of the 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 is at right angles. The performance of a solar panel is highly dependent on the intensity of the light energy as well as the angle of incidence of the sun's rays. The location of the solar array in relation to the sun and the angle of inclination depend on the geographic location of the helium system and the time of year.

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

Industrial solar systems are often equipped with sensors that rotate the solar panel in the direction of the sun's rays, as well as concentrating solar mirrors. In individual systems, such elements significantly complicate and increase the cost of the system, therefore they are not used. The simplest mechanical tilt control system can be applied. In winter, solar panels should be installed almost vertically, this also protects the panel from snow build-up and icing of the structure.

Scheme for calculating the angle of inclination of the solar panel depending on the season

Solar panels are installed on the sunny side of the building to provide the maximum amount of solar energy available during daylight hours. Based on geographic location and solstice level, the battery tilt angle is calculated to best suit your location.

With the complexity of the design, you can create a control system for the angle of inclination of the solar battery depending on the season 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 to be installed on the roof of a house, it is imperative to find out if the roof structure can support the required weight. Independent development of the project involves the calculation of the roof load taking into account the weight of the snow cover in winter.

Choosing the Optimal Static Tilt Angle for Monocrystalline Type Solar Roofing System

For the manufacture of solar panels, you can choose different materials for specific gravity and other characteristics. When choosing materials of construction, 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. When 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 imply cooling of solar cells. Self-fabrication may involve cooling the solar system or controlling the angle of the solar panel to maintain the functional temperature of the module, as well as choosing an appropriate transparent infrared absorbing material.

A competent design of the solar system allows you to provide the required power of the solar battery, which will approach the nominal. When calculating the structure, it should 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 cells will be higher, but the battery will also be much heavier. For the manufacture of 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 cell.

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 provide the work of a computer. A 10 m system gives more than 1 kW of energy and can provide electricity for the operation of basic household appliances: lamps, TV sets, computers. A family of 3-4 people needs about 200-300 kW per month, so a solar system installed on the south side with a size of 20 m 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 / m2 per day, peak consumption power is 3 kW (when the washing machine, refrigerator, iron and electric kettle are turned on) ). In order to optimize energy consumption for indoor lighting, it is important to use low energy consumption AC lamps - LED and fluorescent.

Solar cell frame fabrication

An aluminum corner is used as a frame for the solar battery. Ready-made frames for solar panels can be purchased at ebay. The transparent coating is selected at will, based on the characteristics that are required for a given structure.

Solar Panel Glass Frame Kit starting at $ 33

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

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

When manufacturing a solar cell, it is important to choose transparent materials that do not transmit the infrared spectrum and, thus, reduce the heating of silicon cells that lose their power at temperatures above 250C. The industry uses special glasses with an oxide-metallic coating. The ideal glass for solar panels is considered to be the material that transmits the entire spectrum except for the infrared range.

Scheme 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.

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

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

Plexiglas solar panel

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

Solar battery housing installation

The master class shows the manufacture of a solar panel from 36 polycrystalline solar cells with a size of 81x150 mm. Based on these dimensions, you can calculate the dimensions 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 size of the workpiece should be 835x690 mm with a corner width of 35 mm.

	A home-made 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 835x690 mm are made. To be able to fasten the hardware, holes should be made in the frame.
	Silicone sealant is applied to the inside of the corner twice.
	Be sure to make sure that there are no empty spaces. The tightness and durability of the battery depends on the quality of the 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.
	For reliable fastening of the protective glass, you will need hardware. It is necessary to fix 4 corners of the frame and place two hardware on the long side of the frame and one hardware on the short side around the perimeter.
	The hardware is fixed with screws.
	The screws are tightly tightened with a screwdriver.
	The solar cell frame is ready. Before attaching solar cells, it is necessary to clean the glass from dust.

Selection and soldering of solar cells

At the moment, a huge range of products for self-made solar panels are presented at the Ebay auction.

Solar Cells Kit Includes 36 Polycrystalline Silicon Cells, Cell Leads and Busbars, Schottke Diodes, and Acid Soldering Pen

Since a self-made solar battery is almost 4 times cheaper than a finished one, making it yourself is a significant cost saving. Defective solar cells can be purchased on Ebay, but they do not lose their functionality, so the cost of a solar battery can be significantly reduced if you can additionally sacrifice the appearance of the battery.

Damaged photocells do not lose their functionality

At the first experience, it is better to purchase kits for the manufacture of solar panels, solar cells with soldered conductors are available for sale. Soldering contacts is a rather complicated process, the complexity is exacerbated by the fragility of solar cells.

If you purchased silicon cells without conductors, then 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.
	Carefully place the conductor on the photocell.
	Apply soldering acid and solder to the soldering area. For convenience, the guide is fixed on one side with a heavy object.
	In this position, it is necessary to carefully solder the conductor to the photocell. During soldering, do not press on the crystal, because it is very fragile.

Soldering the elements is a rather painstaking work. If you cannot get a normal connection, then you need to repeat the work. According to the standards, silver sputtering on a conductor must withstand 3 soldering cycles at permissible thermal conditions; in practice, you are faced with the fact that the spraying is destroyed. The destruction of the silver coating occurs due to the use of soldering irons with an unregulated power (65W), this can be avoided by lowering the power as follows - you need to turn on the cartridge with a 100W light bulb in series with the soldering iron. The power rating of an unregulated soldering iron is too high for soldering silicon contacts.

Even if sellers of conductors assure that there is solder on the connector, it is better to apply it additionally. During soldering, try to carefully handle the elements, with minimal effort they burst; do not stack the elements in a bundle, the weight of the lower elements may crack.

Assembling and soldering a solar panel

When assembling the solar battery for the first time, it is better to use a marking substrate, which will help to arrange the elements evenly at a certain distance from each other (5 mm).

Layout substrate for solar cells

The base is made of a sheet of plywood with marking of the corners. After soldering, a piece of mounting tape is attached to each element from the back side, it is enough to press the back panel to the tape, and all the elements are transferred.

Mounting tape used for fixing 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 and rupture of contacts and elements. Only the connecting parts of the structure can be sealed. This type of attachment is more suitable for prototypes, but can hardly guarantee long-term operation in the field.

A sequential battery assembly plan looks like this:

	We spread the elements on a glass surface. There must be a distance between the elements, which implies free resizing without damaging the structure. The elements must be pressed with weights.
	Soldering is carried out according to the wiring diagram below. "Plus" current-carrying tracks are located on the front side of the elements, "minus" ones - on the back side. Before soldering, you need to apply flux and solder, then gently solder the silver contacts.
	All solar cells are connected according to this principle.
	The contacts of the extreme 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 drawing the "middle" point, with its help two additional shunt diodes are placed.
	The terminal is also installed on the outside of the frame.
	This is how the elements wiring diagram looks like without the derived midpoint.
	This is what the terminal strip looks like with the "midpoint" displayed. The "middle" point allows for a shunt diode to be placed on each half of the battery, which will prevent the battery from discharging when the lighting is reduced or one half is dimmed.
	The photo shows a bypass diode at the "positive" output, it resists the discharge of batteries through the battery at night and the discharge of other batteries during partial dimming. Most often, Schottke diodes are used as shunt diodes. They give less loss on the total power of the electrical circuit. A silicone-insulated acoustic cable can be used as current-carrying wires. For isolation, you can use dropper tubes. All wires must be firmly fixed with silicone.
	The elements can be connected in series (see photo), and not by means of a common bus, then the 2nd and 4th row must be rotated by 1800 relative to the 1st row.

The main problems of assembling a solar panel are associated with the quality of the soldering of the contacts, therefore, experts suggest testing it before sealing the panel.

Panel test before sealing, 14 volt mains voltage, 65 W peak power

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

Solar Panel Sealing

Self-sealing solar panels is the most controversial issue among experts. On the one hand, panel sealing is necessary to increase durability and 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.

Sylgard 184 High Elasticity Sealant

On the other hand, if you do not want to incur additional costs, it is perfectly possible to use a silicone sealant. However, in this case, you should not completely fill the elements in order to avoid their possible damage during operation. In this case, the elements can be attached to the back panel with 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, there is a very high probability of rupture of contacts and elements.

	Prepare Sylgard 184 before sealing.
	First, the joints of the elements are poured. The mixture must set in order to secure the elements to the glass.
	After fixing the elements, a continuous polymerizing layer of elastic sealant is made; it can be distributed with a brush.
	This is what the surface looks like after applying the sealant. The sealing layer must dry out. 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

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

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

A more cost-effective alternative to a hybrid battery-grid power system would be a battery-free solar system connected to a central grid. The power supply is carried out 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.

Schemes of three types of photovoltaic systems

Consider a typical installation of a battery-grid photovoltaic system. Solar panels act as a generator of electricity, which are connected through a junction box. Next, a solar charge controller is installed in the network to avoid short circuits during peak loads. Electricity is stored in backup batteries-accumulators, and is also supplied through an inverter to consumers: lighting, household appliances, an electric stove and, possibly, is used to heat water. To install a heating system, it is more efficient to use solar collectors, which belong to alternative solar technology.

AC hybrid battery-grid photovoltaic system

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

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 an output of about 5 kWh;
• accumulators 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, an input voltage of 24-48 V;
• solar discharge controller 40-50 A at a voltage of 24 V;
• uninterruptible power supply for short-term charging with current up to 150 A.

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

In the modern world, it is difficult to imagine existence without electrical energy. Lighting, heating, communication and other pleasures of a comfortable life directly depend on it. This forces us to look for alternative and independent sources, one of which is the sun. This area of ​​energy is still underdeveloped and industrial plants are not cheap. The solution will be to make solar panels with your own hands.

What is a solar battery

A solar battery is a panel consisting of interconnected photovoltaic cells. It directly converts solar energy into electrical current. Depending on the design of the system, electrical energy is accumulated or immediately goes to the energy supply of buildings, mechanisms and devices.

A solar cell consists of interconnected photocells

Almost everyone used the simplest photocells. They are built into calculators, flashlights, batteries for recharging electronic gadgets, garden lights. But the use is not limited to this. There are electric vehicles powered by the sun; in space, this is one of the main sources of energy.

In countries with a lot of sunny days, batteries are installed on rooftops and used for heating and water heating. This type is called collectors, they convert the sun's energy into heat.

Often, the power supply of entire cities and villages occurs only due to this type of energy. Power plants operating on solar radiation are being built. They are especially widespread in the USA, Japan and Germany.

Device

The solar battery is based on the phenomenon of the photoelectric effect, discovered in the twentieth century by A. Einstein. It turned out that in some substances, under the influence of sunlight or other substances, the detachment of charged particles occurs. This discovery led to the creation of the first solar module in 1953.

The materials for the manufacture of elements are semiconductors - combined plates of two materials with different conductivity. Most often, for their manufacture, polycrystalline or monocrystalline silicon with various additives is used.

Under the influence of sunlight, an excess of electrons appears in one layer, and a lack of them in the other. "Extra" electrons move into the region with their deficiency, this process is called pn transition.

The solar cell consists of two semiconductor layers with different conductivity

Between the materials that form an excess and a lack of electrons, a barrier layer is placed to prevent the transition. This is necessary so that the current occurs only when there is a source of energy consumption.

The photons of light hitting the surface knock out the electrons and supply them with the necessary energy to overcome the barrier layer. Negative electrons pass from the p-conductor to the n-conductor, and positive electrons make the return journey.

Due to the different conductivity of the semiconductor materials, it is possible to create a directed motion of electrons. Thus, an electric current is generated.

The elements are connected in series with each other, forming a panel of a larger or smaller area, which is called a battery. Such batteries can be directly connected to a consumption source. But since solar activity changes during the day, and at night it stops altogether, they use batteries that accumulate energy during the absence of sunlight.

The necessary component in this case is the controller. It monitors battery charging and disconnects the battery when fully charged.

The current generated by the solar battery is constant and must be converted to alternating current for use. An inverter is used for this.

Since all electrical appliances that consume energy are designed for a certain voltage, a stabilizer is needed in the system to provide the required values.

Additional devices are installed between the solar module and the consumer

Only in the presence of all these components is it possible to obtain a functional system that supplies energy to consumers and does not threaten to disable them.

Element types for modules

There are three main types of solar panels: polycrystalline, monocrystalline and thin-film. Most often, all three types are made from silicon with various additives. Cadmium telluride and copper-cadmium selenide are also used, especially for the production of film panels. These additives increase the efficiency of the cells by 5-10%.

Crystalline

The most popular are monocrystalline. They are made of single crystals and have a uniform structure. Such plates are in the form of a polygon or rectangle with cut corners.

Monocrystalline cell has the shape of a rectangle with beveled corners

The battery, assembled from monocrystalline cells, has a higher performance in comparison with other types, its efficiency is 13%. It is lightweight and compact, is not afraid of slight bending, can be installed on an uneven surface, service life is 30 years.

The disadvantages include a significant decrease in power when it is cloudy, up to the complete cessation of energy production. The same happens when dimming, the battery will not work at night.

The polycrystalline cell is rectangular, which allows the panel to be assembled without gaps

Polycrystalline ones are produced by casting, have a rectangular or square shape and an inhomogeneous structure. Their efficiency is lower than monocrystalline, the efficiency is only 7-9%, but the drop in production during cloudy, dusty or dusk is insignificant.

Therefore, they are used in the device of street lighting, they are also more often used by homemade products. The cost of such plates is lower than monocrystals, the service life is 20 years.

Film

Tocfilm or flexible elements are made of amorphous silicon. The flexibility of the panels makes them mobile, rolled up in a roll they can be taken with you on trips and have an independent source of energy anywhere. The same property allows them to be mounted on curved surfaces.

The film battery is made of amorphous silicon

In terms of efficiency, film panels are two times inferior to crystalline ones; to produce the same amount, double the area of ​​the battery is required. And the durability of the film does not differ - in the first 2 years, their effectiveness drops by 20-40%.

But when it is cloudy or darkened, energy production is reduced by only 10-15%. Their relative cheapness can be considered an undoubted advantage.

What can be used to make a solar panel at home

Despite all the advantages of industrial batteries, their main disadvantage is their high price. This trouble can be avoided by making the simplest panel with your own hands from scrap materials.

Of diodes

A diode is a crystal in a plastic case that acts as a lens. It concentrates the sun's rays on the conductor, resulting in an electric current. By connecting a large number of diodes together, we get a solar battery. You can use cardboard as a board.

The problem is that the power of the received energy is small, it will take a huge number of diodes to generate a sufficient amount. In terms of financial and labor costs, such a battery is much superior to the factory one, and in terms of power it is much inferior to it.

In addition, the output drops sharply with decreasing illumination. And the diodes themselves behave incorrectly - often a spontaneous glow occurs. That is, the diodes themselves consume the generated energy. The conclusion suggests itself: ineffective.

Of transistors

As in diodes, the main element of a transistor is a crystal. But it is enclosed in a metal case that does not allow sunlight to pass through. To make a battery, the case cover is cut off with a hacksaw for metal.

A low-power battery can be assembled from transistors

Then the elements are attached to a plate made of PCB or other material suitable for the role of a board, and connected to each other. In this way, you can assemble a battery, the energy of which is enough to operate a flashlight or radio receiver, but you should not expect high power from such a device.

But as a travel energy source of low power is quite suitable. Especially if you are carried away by the process of creation itself and the practical benefits of the result are not very important.

Craftsmen suggest using CDs and even copper plates as photocells. A portable phone charger is easy to make from photocells from garden lights.

The best solution would be to buy ready-made plates. Some online sites sell modules with a small manufacturing defect at an affordable price, they are quite suitable for use.

Rational battery placement

How much power the system will produce depends to a large extent on the placement of the modules. The more rays hit the photocells, the more energy they will produce. For optimal placement, the following conditions must be met:

Important! The battery current is set by the capacity of the weakest cell. Even a small shadow on one module can reduce system performance by 10 to 50%.

How to calculate the required power

Before proceeding with the assembly of the battery, it is necessary to determine the required power. The number of cells purchased and the total area of ​​finished batteries depends on this.

The system can be both autonomous (independently providing electricity to the house), and combined, combining the energy of the sun and a traditional source.

The calculation consists of three steps:

1. Find out the total power consumption.
2. Determine sufficient battery capacity and inverter capacity.
3. Calculate the required number of cells based on the insolation data in your area.

Power consumption

For an autonomous system, you can determine it by your electricity meter. Divide the total monthly energy consumption by the number of days to obtain the average daily consumption.

If only part of the devices will be powered by the battery, find out their capacity according to the passport or marking on the device. Multiply the obtained values ​​by the number of hours of work per day. Adding the obtained values ​​for all devices, you get the average consumption per day.

AB capacity (storage battery) and inverter power

AB for solar systems must withstand a large number of discharge and discharge cycles, have a low self-discharge, withstand a large charging current, operate at high and low temperatures, while requiring minimal maintenance. These parameters are optimal for lead-acid batteries.

Another important indicator is the capacity, the maximum charge that the battery can accept and store. Insufficient capacity is increased by connecting the battery in parallel, in series, or by combining both connections.

Calculation will help to find out the required amount of AB. Consider it for concentrating the energy reserve for 1 day in an AB with a capacity of 200 A.h and a voltage of 12 V.

Suppose the daily demand is 4800 V. hour, the output voltage of the system is 24 V. Considering that the losses on the inverter are 20%, we introduce a correction factor of 1.2.

4800: 24x1.2 = 240 A.h

The depth of discharge of AB should not exceed 30-40%, let's take this into account.

240x0.4 = 600 A.h

The resulting value is three times the capacity of the battery, therefore, to supply the required amount, 3 ABs connected in parallel are required. But at the same time, the voltage of the battery is 12 V, in order to double it, you will need 3 more batteries connected in series.

To obtain a voltage of 48 V, connect two parallel chains of 4 AB in parallel

The inverter is used to convert DC to AC. They choose it according to the peak, maximum load. On some consuming devices, the starting current is much higher than the rated one. It is this indicator that is taken into account. In other cases, the nominal values ​​are taken into account.

The shape of the voltage is also important. The best option is a pure sine wave. For devices that are insensitive to voltage drops, a square shape is suitable. You should also take into account the possibility of switching the device from AB directly to solar panels.

Required number of cells

Insolation indicators differ greatly in different areas. For a correct calculation, you need to know these numbers for your area, the data is easy to find on the Internet or at a weather station.

Insolation table by months for different regions

Insolation depends not only on the season, but also on the angle of inclination of the battery

When calculating, be guided by the indicators of the lowest insolation during the year, otherwise the battery will not generate enough energy during this period.

Suppose the minimum is in January, 0.69, and the maximum is in July, 5.09.

The correction factor for winter time is 0.7, for summer time - 0.5.

The required amount of energy is 4800 Wh.

One panel has a power of 260 W and a voltage of 24 V.

Losses on AB and inverter are 20%.

We calculate the consumption taking into account losses: 4800 × 1.2 = 5760 Wh = 5.76 kWh.

We determine the performance of one panel.

Summer: 0.5 x 260 x 5.09 = 661.7 Wh.

In winter: 0.7 × 260 × 0.69 = 125.5 Wh.

We calculate the required number of batteries by dividing the consumed energy by the performance of the panels.

In summer: 5760 / 661.7 = 8.7 pcs.

In winter: 5760 / 125.5 = 45.8 pcs.

It turns out that for full provision, in winter, five times more modules will be needed than in summer. Therefore, it is worthwhile to immediately install more batteries or provide for a hybrid power supply system for the winter.

How to assemble a solar panel with your own hands

The assembly consists of several stages: manufacturing the case, soldering the elements, assembling the system and installing it. Before starting work, stock up on everything you need.

The battery consists of several layers

Materials and tools

• photocells;
• flat conductors;
• alcohol rosin flux;
• soldering iron;
• aluminum profile;
• aluminum corners;
• hardware;
• silicone sealant;
• hacksaw for metal;
• screwdriver;
• glass, plexiglass or plexiglass;
• diodes;
• measuring instruments.

It is better to order photocells complete with conductors, they are specially designed for this purpose. Other conductors are more fragile, which can be problematic when soldering and assembling. There are cells with wires already soldered. They are more expensive, but significantly save time and labor costs.

Purchase plates with conductors, this will shorten the running time

The frame of the case is usually made of an aluminum corner, but it is possible to use wooden slats or 2x2 square bars. This option is less preferable because it does not provide sufficient weather protection.

For a transparent panel, choose a material with the lowest refractive index of light. Any obstacle in the path of the rays increases the energy loss. It is desirable that the material transmits as little infrared radiation as possible.

Important! The more the panel is heated, the less it generates energy.

Frame calculation

The dimensions of the frame are calculated based on the size of the cells. It is important to provide a small distance of 3-5 mm between adjacent elements and take into account the width of the frame so that it does not overlap the edges of the elements.

The cells are available in various standard sizes, consider the option of 36 plates, 81x150 mm in size. We arrange the elements in 4 rows, 9 pieces in one. Based on these data, the dimensions of the frame are 835x690 mm.

Box making

Soldering of elements and assembly of modules

If the elements are purchased without contacts, they must first be soldered to each plate. To do this, cut the conductor into equal lengths.

1. Cut a rectangle of the correct size out of cardboard and wrap a conductor around it, then cut on both sides.
2. Apply flux to each conductor, attach the strip to the element.
3. Solder the conductor carefully along the entire length of the cell.

   Solder conductors to each plate

4. Place the cells in a row one after the other with a gap of 3-5 mm and sequentially solder together.

   During installation, periodically check the functionality of the modules

5. Transfer the finished rows of 9 cells into the body and align with each other and the frame outline.
6. Solder in parallel using wider rails and observing polarity.

   Lay the rows of elements on a transparent backing and solder together

7. Print the contacts "+" and "-".
8. Apply 4 drops of sealant to each element and place a second glass on top.
9. Let the glue dry.
10. Fill with sealant around the perimeter so that moisture does not get inside.
11. Fasten the panel in the case using the corners, screwing them into the sides of the aluminum profile.
12. Install a Schottke blocking diode with a sealant to prevent the battery from discharging through the module.
13. Provide the output wire with a two-pin connector, then connect the controller to it.
14. Screw the brackets to the frame for attaching the battery to the support.

Video: soldering and assembling the solar module

The battery is ready, it remains to install it. For more efficient work, you can make a tracker.

Rotary mechanism manufacturing

The simplest rotary mechanism is easy to make yourself. Its principle of operation is based on a counterbalance system.

1. From wooden blocks or aluminum profiles, assemble a support for the battery in the form of a ladder.
2. Using two bearings and a metal rod or pipe, place the battery on top so that it is anchored in the center of the larger side.
3. Orient the structure from east to west and wait for the sun to be at its zenith.
4. Rotate the panel so that the rays fall on it vertically.
5. Attach a container of water at one end, balance it at the other end with a weight.
6. Make a hole in the container so that the water flows out a little.

As the water flows out, the weight of the vessel will decrease and the edge of the panel will rise upward, turning the battery to follow the sun. The size of the hole will have to be determined empirically.

The simplest solar tracker is made according to the principle of a water clock.

All you need is to pour water into a container in the morning. Such a structure cannot be installed on the roof, but it is quite suitable for a garden plot or a lawn in front of the house. There are other, more complex tracker designs, but these are expensive.

Video: how to make your own electronic solar tracker

Installing Batteries

Now you can test and use free electricity.

Service modules

Solar panels do not require any special maintenance, as they have no moving parts. For their normal functioning, it is enough from time to time to clean the surface from dirt, dust and bird droppings.

Use the garden hose to clean the batteries; with good water pressure, you don't even need to climb onto the roof. Check the serviceability of additional equipment.

How soon the costs will pay off

You should not expect immediate benefits from the solar power supply system. Its average payback is approximately 10 years for an autonomous home system.

The more energy you consume, the faster your investment will pay off. Indeed, for both small and large consumption, the purchase of additional equipment is required: a battery, an inverter, a controller, and they leave a small part of the cost.

Consider also the service life of the equipment, and the panels themselves, so that you do not have to change them before they pay off.

Despite all the costs and disadvantages, solar is the future. The sun is a renewable energy source and it will last at least another 5 thousand years. And science is not standing still, new materials for photocells appear, with much higher efficiency. This means that soon they will be more affordable. But you can use the energy of the sun now.

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

However, many do not dare to install a solar system because of the high cost of arranging the complex. You can reduce the cost of production if you start creating it yourself. Doubt about your own abilities?

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

According to statistics, an adult uses about a dozen different network-powered devices every day. Although electricity is considered a relatively green energy source, it is an illusion because it uses resources that pollute the environment.

What components are needed and where to buy them

The main detail is a solar panel. Typically, silicon wafers are bought over the Internet with delivery from China or the United States. This is due to the high price of domestically produced components.

The cost price of domestic plates turns out to be so high that it is more profitable to order on Ebay. With regard to rejects, only 2-4 plates out of 100 are unusable. If you order Chinese plates, then the risks are higher, because the quality is poor. The only advantage is the price.

The finished panel is much more convenient to use, but also three times more expensive, so it's better to be puzzled by the search for components and assemble the device with your own hands.

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

Image gallery

Alternative energy is now being dealt with not only by specialists. Options for autonomous power supplies are also of interest to amateurs who are friends with electrical and radio engineering. With regard to solar panels, the main difficulty in the implementation of the project is their high price. And if we consider that several panels are needed for a private house, then some skepticism in terms of their use in everyday life becomes clear.

Although there is a good solution for those who are used to doing everything with their own hands - to assemble a solar panel from separate panels. For example, Chinese, which are relatively inexpensive.

From the experience of their practical application, we can conclude that they fully meet the expectations of the master. And if you focus on a class B kit (cheaper products), then the savings when assembling the power source yourself are significant.

To obtain a sample of 145 W with a total voltage of 18 V, you will have to pay for Chinese panels (36 pieces) about 3,100 rubles (if purchased via the Internet, for example, on Alibaba, Ebay) versus 6,180 (the cost of a ready-made analogue of industrial production). It turns out that it makes sense to spend time and make such a battery.

Not only Chinese, but all solar panels are divided into mono- (more expensive) and polycrystalline (amorphous). What is the difference? Without going into the manufacturing technology, it is enough to point out that the former are characterized by a homogeneous structure. Therefore, their efficiency is higher than that of amorphous analogs (about 25% versus 18%) and they are more expensive.

Visually, they can be distinguished by their shape (shown in the figure) and shade of blue. Monocrystalline panels are slightly darker. But whether there is any sense in saving on power, you will have to decide on your own. In addition, it should be borne in mind that the production of inexpensive polycrystalline panels in China is mainly carried out by small firms, saving on literally everything, including starting materials. This directly affects not only the cost price, but also the quality of the product.

All photocells are connected in a single energy chain by conductors. Depending on the type of panels, they may be already fixed in place or missing. This means that you will have to solder them with your own hands. All crystalline samples are fragile and must be handled with extreme care.

If you do not have the proper skills to work with a soldering iron, then it is better to purchase panels of class A (more expensive). When buying cheap analogs (B), it is advisable to take at least one in stock. The practice of assembling solar panels shows that damage cannot be avoided for sure, so an extra panel will definitely be needed.

When determining the required number of photocells, you can focus on such data. 1 m² of panels gives approximately 0.12 kWh of electricity. Energy consumption statistics show that for a small family (4 people), about 280 - 320 kW is enough per month.

Solar panels are sold in two options - wax coated (to protect against damage during transit) and without it. If the panels have a protective layer, then they will have to be prepared for assembly.

What needs to be done?

• Unpack the product.
• Immerse the kit in hot water. The approximate temperature is 90 ± 5 ° C. The main thing is that it is not boiling water, otherwise the panels will be partially deformed.
• Disconnect samples. Signs that the wax has melted are visible visually.
• Treat each panel. The technology is simple - they are alternately immersed in hot soapy water, then clean. The “ablution” procedure continues until there are no traces of wax on the surface.
• Dry. The panels should be laid out on a soft cloth. For example, on a terry tablecloth.

Assembly order

Specificity of frame manufacturing

In fact, this is a traditional simple frame, the material for which is selected depending on the location of the battery. Usually on thematic sites, an aluminum corner or wood is indicated. The expediency of using the latter (with all due respect to the authors of the articles) raises certain doubts. The main reason is in the peculiarities of any tree. It consists in the moisture content, regardless of the degree of drying.

No matter how much it may be, twisting or even cracking of the tree cannot be avoided. Given the fragility of the panels - not an option, definitely. For a long time, even when attached to a window inside a building, it will not serve.

Battery installation

The dimensions of the frame are selected based on the linear parameters of the panels. Horizontal or vertical orientation - it depends on the specifics of the battery installation, and does not matter in principle.

A sheet of glass or polycarbonate is attached to the frame (only not cellular, but monolithic). It performs a protective function, protecting the photocells from mechanical damage.

On it, from the inside of the frame, drops of silicone sealant are applied (in the center of the panels), or it is smeared with a thinnest layer. Recommendations for the use of resin (epoxy) hardly deserve attention, since in this case there is no need to talk about the maintainability of the battery.

The estimated number of panels fits into the frame (assembly is done in advance). One gives a voltage of about 0.5 V (a small deviation in the nominal value does not count). Here it is important not to confuse where the front side of the products is and where the back is.

The back is covered with a soft removable mat. To make it with your own hands, you can take foam rubber (4 cm, at least) and polyethylene film. Its edges are connected with tape or soldered (if there is a special machine).

The work doesn't end there. Air bubbles will remain between the glass (polycarbonate) and the panels, which will reduce the efficiency of the solar panel. They need to be removed. For this, a dense material is laid on the mat. For example, a fragment of thick (multi-layer) plywood, matched to the dimensions of the frame.

Above - a weight, the weight of which is sufficient to slightly press down the panels. In this position, the battery is left for half a day, no less. Here you should focus on its dimensions and uniformity of load distribution.

After this time, bends, plywood and mat are dismantled. It is impossible to immediately fix the battery at the installation site. It will take some more time for the sealant to dry completely.

Instead of a mat, you can also use another soft backing. For example, sawdust, shavings.

The final stage is the manufacture of the back wall and its setting in place. For this, chipboard, fiberboard, plywood are taken, but always with the same substrate to protect the panels from deformation.

Circuit assembly features

The bonding of plates is a complex process that requires painstaking and attentiveness. It is better to work with a low-power soldering iron (24 - 36 W). If used in everyday life at 65, then it should be turned on through a limiting resistance. The simplest option is to connect a hundred-watt light bulb in series.

But that's not all. It is necessary to exclude self-discharge of the battery (at night, in inclement weather). This is ensured by the inclusion of p / p diodes in the circuit. It is advisable to use an acoustic cable as a conductor (for conclusions), which is also fixed on the panel with a sealant.

The option of a film solar battery (there is one) is not considered. Despite some advantages, it has a number of significant disadvantages - low efficiency and the need for laying over large areas. For a private house, the solution is unacceptable.

Modern realities are such that alternative food sources are by no means a cheap pleasure. Not everyone has the opportunity to order the installation of solar panels from a supplier, so a do-it-yourself solar battery is becoming popular.

It is not difficult to make a solar panel. To do this, you will need: solar cells, flux (a pencil that is easy to apply, but it is quite normal to use rosin), alcohol, a 40-watt soldering iron, cotton swabs, a wide bus (up to 2 meters) and a narrow bus (1.6 mm) ). The narrow bus is a tinned wire (copper flat, which is covered with tin). When the sun is shining, the temperature of the solar battery rises tremendously, causing expansion; at night, the opposite process occurs - contraction. You can, of course, take a wider tire - 2 mm, but practice shows that the optimal width is still 1.6 mm.

The first step is to sort the solar cells. Each of them produces 0.26-0.35 volts. They need to be sorted in order to choose approximately the same at face value. Their number should be 36. If there is at least one element with a low index in the battery, it will be resistance, which is undesirable.

We cut the tire (there should be 72 strips), determining its length by the width of two elements located at a distance of five to ten millimeters from each other.

Video: The complete process of making a solar panel with your own hands

Video: Homemade solar battery with your own hands from two glasses

Video: DIY solar panel assembly of the panel

Video: Building a Solar Battery with your own hands

We wipe well the places of future soldering on the elements with alcohol in order to degrease them. To begin with, it is enough to take three elements. Then, we draw on them with a pencil (the tire does not need to be degreased, because it is tinned). We solder the tire, which lays down easily, so there is no need to apply strong efforts to it. Having installed the soldering iron in one place, wait until the tire begins to melt, and after that, slowly lead the soldering iron along the entire tire.

Photo: Soldering a solar battery with your own hands

Then carefully remove the remaining flux with alcohol and a cotton swab. In this way, all other elements are prepared. Now you can solder from the back side, also wiping with alcohol and applying flux, already connecting the elements into a socket (9x4 cells).

Be sure to remove excess flux. The reverse side will have positive potential at any point.

Now the structure needs to be transferred to the front surface - in our case it is cast acrylic of the Altuglas company with a thickness of 5 mm. You can, of course, directly on the front side and solder the photocells (this will even be more convenient).

We lay the ribbons with solar cells in such a way that on the first ribbon the first bus goes from the bottom, the second from the top. On the second, in the reverse order: the first is on top, the second is on the bottom, etc. This will provide a serial connection.

We solder these outlets of the narrow bus to the wide bus, removing the remains with the help of nippers. Before rolling the film, measurements must be taken to make sure everything is done correctly.

You also need to check if there are very hot panels (with your hand). If there are any, we will replace them. If not, roll on the film 751 oracal, which is intended for gluing applications on cars. The warranty period for its operation is seven years. But, from experience, this period is much longer. We do this very carefully so that there are no distortions, because it is no longer possible to peel it off. In extreme cases, if this happens, the film must be carefully cut and glued. Do not press the film against the elements. From the center it is leveled to the edges, pressing only in places where there are no elements. Do not pay attention to small bubbles - they will go away when rolling. Separate the film from the base by a centimeter, no more. We again check the parameters (volts and short-circuit current). A current of four amperes indicates that everything is correct with us.

It remains to place the structure in the frame.

Solar cell frame

Plexiglass is suitable as a transparent layer, but over time it warps and turns yellow, which affects the performance of the battery. You can use ordinary glass, which allows you to reduce the heating of solar cells, due to the fact that it does not transmit the infrared spectrum. Finally, there is acrylic glass, which neither degrades transparency over time nor warps.

Aluminum corners, chipboard, plywood and other materials are most often used as the body.

The last step is sealing

Compounds are used for sealing (mainly abroad). But they cost decently, so our craftsmen use either silicone sealant, or a protective film (as described above), or mixed with sealants, acrylic varnish.

Soldering photocells

On sale you can find photocells with soldered conductors, but more often you have to do it yourself. What do you need to know? The first is that you need to work very carefully with photocells - they are fragile and expensive.

Where to buy photocells?

The easiest way is to type a query in the browser - there will be enough results, including private entrepreneurs who offer the elements necessary to create a solar battery. True, they are quite expensive - much cheaper can be found on Ebay. You can, of course, buy items that were rejected in production for various reasons: they will cost much cheaper, but there is a risk that they will turn out to be unsuitable for use by folk craftsmen. Plus, shipping can cost up to thirty dollars.

How to choose photocells

Typically, you can find monocrystalline and polycrystalline photovoltaic converters. The former have a longer service life - up to thirty years, but they are sensitive to weather changes. The latter, on the contrary, do not reduce the power too much when it is cloudy, but differ in a shorter service life. In addition, compared to monocrystalline ones with an efficiency of 13%, they have it from seven to nine percent.

In order to use the solar battery more efficiently, it is necessary to provide for a change in the angle of inclination.

Conclusion

Making a solar panel with your own hands turned out to be not so difficult. And much cheaper than ordering it from a supplier!