How to install solar panels on the roof

Sunny power station for a house 200 m2 with your own hands

Often on the network, reports of the struggle for ecology, the development of alternative energy sources. Sometimes they even conduct reports on how a solar power plant was made in an abandoned village so that local residents can use the benefits of civilization not 2-3 hours a day while the generator works, but constantly. But all this is somehow far from our lives, so I decided to show and tell how it works and how the solar power plant for a private house works by my example. I’ll tell you about all the stages: from the idea to the inclusion of all devices, as well as share the experience of operating. The article will turn out rather big, so who does not like many letters can see the video. There I tried to tell the same thing, but it will be seen how I myself collect all this myself.

Starting data: a private house with an area of ​​about 200 m2 connected to electric networks. Three.Phase entry, with a total capacity of 15 kW. The house has a standard set of electrical appliances: refrigerator, TVs, computers, washing and dishwashers and so on. The power grid does not differ in stability: the record I recorded. A shutdown of 6 days in a row for a period of 2 to 8 hours.

What I want to get: forget about the interruptions in electricity and use electricity, no matter what.

What bonuses can be: to maximize the use of the energy of the Sun so that the house priority eats solar energy, and the deficiency is made from the network. As a bonus, after the adoption of the law on the sale of electricity to the network, to start compensating for part of their costs, selling excess production in a common power supply.

Places for installation

When choosing the location of solar panels, it is worth considering several important criteria. Only then can you determine where it is best to arrange the modules on the site so that it is given the best effect. The main recommendations are as follows:

• For the northern hemisphere, it is necessary to orient the solar panels in the south, for the southern. On the contrary. This is an ideal position, but if it is not possible to arrange a slope strictly south, the southeast or southwest will do.
• The slope also needs to be selected depending on the region. The easiest option, which experts advise. The angle of inclination should be approximately equal to the breadth on which the house is located. For example, Moscow is at 55 latitude, but it is not always possible to raise the modules to such a corner, so the maximum possible value is taken.
• You can put solar panels only where there is no shadow. If the surface is shaded, then the efficiency of work will be low. Trees and other plants can be removed, but if the buildings interfere, it will not work to solve the problem.
• Choose an option that is convenient to maintain. The batteries themselves do not need special care, but several times a season you need to wash the surface. From dust and pollution, effectiveness is reduced. It is also necessary to provide access to all connections and modules, they must also be periodically checked.
• Take into account the permissible load on the roof if the system is located there. Most often, there are no problems, since the batteries weigh a little, but if the rafter system is old, and the roof is not very reliable, you need to either redo it or strengthen it.

For maximum effect, it is advisable to change the angle of batteries. Increase 12 degrees for the summer, and reduce the same amount for the winter.

At home or other building. The most common solution that saves space and reduces the likelihood of accidental damage. At the same time, electricity enters the building immediately, which increases the efficiency of the system. For all types of roofs there is a finished fastener, so there will be no problems with the installation of problems.

You can use two installation options, it is not necessary to put all solar panels in one place.

It will be useful to familiarize yourself: we mount 300 solar panels on our own

Place for the inverter

This equipment converts a direct current from solar batteries into alternating, which is used by all household appliances. It should be selected based on their characteristics of the panels. Everything is calculated in the project, so you need to buy an option with the desired characteristics. When choosing a place, you should take into account the following:

• The closer the converter to the current source, the less energy is lost during transmission and the more efficient the system works. Therefore, if possible, it should be placed as close to the connection point as possible.
• When installing panels on the roof or wall of the house without the use of batteries, it is best to put an inverter in the attic. The temperature there is suitable for equipment, it is better to prepare a place in advance, provide good ventilation to exclude overheating in the summer.
• Ensure the convenience of servicing the converter. Do not put it in places with limited access, since from time to time you need to clean the body from dust and check the compounds. In order not to constantly control the readings, it is better to choose models with a wireless module so that the data is transmitted to the Internet and you can watch them through a smartphone or computer.

The main thing is not to put the equipment too far and protect it from adverse effects. Comply with the recommendations of the installation manufacturer in order to exclude any problems.

Installation, connecting solar panels and installing them on the roof

A photoelectric converter (solar module, photoelectric module, solar panel) is a kind of square or rectangular tablet consisting of a light frame (for frame performance) and, in fact, a working surface. The dimensions of the converters can be very different, for example: 285 x 425, 455 x 995 560 x 1180, 805 x 1575 and depend on the purpose of use. Their capacities are also diverse: from 30 watts to 165 watts or more.

For private economy, 60 W, 70 W, 80 W, 120 W, with dimensions of 560 x 1180, 805 x 1575, are more popular for private farming, since the process of installing them, for example on a roof, does not require much effort and attracting lifting and transport mechanisms. Due to their technical characteristics, they are optimal in terms of the ratio of the area. Nominal power. This is important for choosing the area of ​​their working placement.

In central Russia, the density of the solar radiation flow on a sunny summer day is from 700 to 800 watts per square meter of area (at 20 ° C). The efficiency of solar modules is 14. 16%, t. E. A 80-wound module with dimensions of 560 x 1180 will provide approximately 80 W electrical power.

The module does not have mechanical mobile nodes, and this favorably affects its practicality in operation. Planning. Preventive maintenance is minimized. The service life reaches 20-30 years.

The traditional execution of modules provides for options: 12 V, 24 V. To obtain other standard voltage levels and the required power, individual modules are accordingly switched to batteries. You can switch them sequentially, in parallel and sequentially. In parallel.

The working position of the modules should be selected so that the sun’s rays are directed to the working surface at an angle close to 90 °. In this case, the effectiveness of the module will be maximum. In cases of private use, it is not advisable to build automatic support devices for the movement of the sun (the principle of sunflower), and in industrial installations, when developing a large amount of energy, this is profitable and gives a tangible positive result.

Connection of solar batteries is not a complicated procedure, but still you should observe a certain connection sequence and not forget the precautionary measures. Firstly, batteries are mounted, as a rule, at a height, most often on the roof. This is in itself a danger. Secondly, remember. Solar panels are source of electric energy and are ready to fulfill their function at any time, regardless of whether you expect it or not.

Connecting solar panels on Earth

The first and unconditional rule, which applies not only to solar panels, but installation work at altitude, in general. All that can be done and prepared below is done below. What you can easily be able to do on Earth is five times more difficult for you to make it at a height.

You should start the connection with the fact that close the working surface of the solar batteries with a dense fabric or paper and secure them on batteries, for example, painting tape. This must be done immediately in order to prevent a random short circuit of the conclusions that you have to draw.

I want to make a reservation right away. Despite the fact that in any installation of electrical circuits, additional contacts should be avoided in order to minimize the probability of failure. Any additional contact weakens sooner or later and if it does not restore it in time, the refusal (breakdown) is inevitable. But in this case, I strongly recommend drawing conclusions from each solar battery exactly such a length that it (length) is enough to get them inside the room and already inside (under the roof) set a set of terminal clamps for switching batteries as required according to the scheme.

I advise you to do this so that at any time, at any weather, you can, if necessary, do a cross. This will also allow, being under the roof of the house, to check the performance of each of the batteries, to make, if necessary, measurements, etc.D.

You can draw conclusions either with a two.Core flexible cable, for example, kg, or a PV3 wire, but be sure to protect against mechanical damage and direct sunlight with a rustle with a resistance to sunlight. The cable, too, if you choose not in the sunscreen, provide for hide from sunlight. This will extend his service life. Do not spare the cross section. Choose at least 4 kV. Mm, better 6 kV. Mm copper.

After you closed the working surface of the solar panels and made the necessary conclusions the necessary length, the time has come to take care of their fasteners on the roof. You can do in different ways, but the three requirements for installation remain unchanged:

The place of placement of solar batteries on the roof should be chosen so that their working surface or part is not shaded throughout the daylight day, t. E. For them, you need to choose a completely open place.

The slope of solar batteries should provide a perpendicular orientation of sunlight to the working surface. In summer it is 30 degrees to the horizon, in winter. 60 degrees. At such angles, the return of solar panels will be maximum.

Understanding that when heated by solar panels, the effectiveness of their work is reduced, there must necessarily provide air gaps between the roof and the back of the batteries, for natural ventilation. This item belongs to those cases when the slope of the roof already provides the angle of orientation of the batteries to the sun and they are attached parallel to the existing roof coating on the very roof itself.

Despite the fact that you closed the working surface of the solar modules, insulate the ends of the conclusions with insulating tape. God saves man, who save himself.

On this, preparatory work on connecting solar batteries is completed and you can move to the roof.

Installation of solar batteries on the roof

What fasteners will be needed

The mount depends on the type of roof and roofing material. It is not difficult to choose fasteners if you understand its features. There are few options, everyone has their own nuances:

• Installation of the panels themselves is carried out on special guides, which are usually suitable for all types of fasteners. That is, this part of the structure is always the same and does not depend on the type of roof and roofing material. To simplify the work and reduce the load on the roof, the guides are made of aluminum or alloys based on it.
• Clips fixing panels are also always the same. They are attached in the guide and at the expense of the legs of a special shape press the body to the surface. They can be divided into one.Sided, which are placed at the edges and bilateral, used between panels.
• For reliable docking of the guides, special connectors are made. Also in the design there are always ground terminals that combine the entire frame into the overall contour and ground it.

Do not use homemade mounts. If they spoil the panels, you will have to change them at your own expense.

Energy export to power grid

Finally, we approached the issue of energy export into the mains. Everything is just from a technical point of view, but everything is complicated with the economic. Technically, we simply add a new source of energy to our household. Which will be spent by connected devices, and excess through an electric meter (this is important) will go to the city network. The counter is important here because it will depend on it how the exported energy will be calculated.

• The old disk counter during the reversal of tension is likely not to turn the disk (it has a special stopper in it), t.E. The electricity we have developed will be given to the network for free, Indications on the counter will not change.
• The old disk counter without a stopper will twist the disk in the opposite direction, t.E. The counter readings will be decrease, which, of course, is beneficial to the owner of the solar panels. But such counters are not available now and have become a museum rarity.
• A digital counter that does not know how to count the export of electricity will consider it “according to the module” regardless of the direction, t.E. For every Distributed The city of the city of the solar panels will be to pay as for consumed.
• A modern digital counter, which can count both export and electricity import, will show separate values ​​in all respects. In total, there are 4 replacement options on such a meter of each other’s option: daytime import, nightly, export of daytime, export night.

Of course, for a 100-200W balcony station, this is not so critical, most electricity will most likely be consumed inside the apartment by a refrigerator and other devices. So even if someone does not have a modern electric meter, it is easier to consider this only as a charity contribution to the ecology-even if you “give” the city a few kWh per month and pay for them, let’s say 50, it is unlikely that the owner will impoverish from this. It is easier to believe that this money will go to the development of electric networks Of course, if there are really many panels, it is advisable to put a special Grid-Tie inverter with the so-called limiter-the current sensor, which is placed immediately after the electric meter and limits the production of the inverter so that nothing is given out to the outside.

In my case, the modern counter was already installed for free by the municipality, so on a sunny day on the screen you can really see the negative values ​​of the electricity consumed:

By the way, the question of how much can be “earned” on the electricity generated and sold to the state, economically very difficult. In Germany, for example, special preferential tariffs for the given electricity were introduced at first, which additionally motivated the owners to put solar panels. But then the benefits began to be canceled, and now, it seems that it is no longer so profitable. A similar law on the Green Tariff with really high for generation was adopted in Ukraine, and this led to a significant increase in the number of solar stations, but how long it will last for a long time is unknown. It is clear that in Ukraine they want to get maximum energy dependence from neighbors, so the of buying electricity are still high. In Russia, on the contrary, the generated electricity will be purchased cheaper than the consumed. Energy resources in and so in abundance, and the government has no desire to motivate people to install solar panels. But in any case, we are talking about Excess. The electricity that is consumed inside the house is direct and clean savings, reducing payments at the usual tariff, but only surplus are sold to the state. In theory, the purpose of installing solar panels for the homeowner is to reduce the consumption of electricity from the external network to zero, and the ability to sell surplus to the city is only a pleasant bonus, but not an end in itself.

By the way, if we talk about payback at the present time, judging by the German online calculator, the payback for panels on the roof of 31m2 is about 9 years for Germany:

Characteristics of the solar panels affecting their installation

It is for the process of fixing to the roof that the type and technology of photographic elements. Mono, poly, thin film. Are insignificant. But power and effectiveness can still affect the installation of solar panels. For example, if the house has a north of a roof with a limited surface, then more effective products can be put there, the rest. On the southern part, better warmed by the sun.

If for some reason the user considers it appropriate to combine products of different companies or types of panels, then this is also possible with suitable parameters for the selected architecture of the system.

Roofing roofs from solar batteries should always take into account roofing. For example, if the frame consists of OSB plates, this gives wider possibilities for placing fasteners.

On sale there are standard unified sets for fixing solar panels with all the necessary elements. From manufacturers you can also order the right amount and set parameters for individual needs.

After you deal with the installation, we recommend that you find out: how to connect the solar panels to the battery and the consumption source.

Sunny batteries on the roof of the Autodoma. Autonomous Energy

During long travel and parking, the camp with electric energy is quite acute. Someone travels without a refrigerator at all and uses only lighting of the salon. Our main consumer of energy is my laptop, since I am engaged in the processing and installation of the video on trips, and MacBuk about at high load eats as not in itself. That is why, in addition to the standard starter battery, I installed three more AGM batteries in the salon with a total capacity of 285Ah.

During the evening and night during the parking, we usually spend 30-40% of the capacity of the batteries, for them it is just the most gentle mode of operation. But at such a pace “to zero” they will be discharged in a day and a half, so they have to be recharged. I do not want to start a diesel engine for an hour and a half to two hours, and prolonged work at idle does not benefit any motor.

So solar panels come to the rescue. Perhaps one of the most necessary things for autonomous travels on Kemper.

The total length of the van is 7 meters, and the plane of the roof has dimensions 430×150 centimeters. It would be strange not to use such a huge space, so from the factory we equipped the machine with rods for installing the rails that will be used to attach the marquise (side canopy) and solar panels. By the way, pay attention to the round plastic cork behind the rear view camera-fortunately, Mercedes-Benz engineers have provided that someone may feel sorry for the roof to extend the wiring.

The main criterion was the size (and there are only a few possible options), they had to occupy the maximum possible space on the roof, and at the same time there should have been a place to place the marquise.

I came to the conclusion that the installation of two batteries in size 200x100cm one after another will be ideal for me. And then in terms of the ratio of “price/power” stopped at the domestic manufacturer Sunways. Of the “pluses”. Everything is available, I bought the whole set in one place (made a discount) and the manufacturer’s guarantee for the lack of factory marriage.

And here are the “batteries” themselves. Live turned out to be larger and harder than I represented. By the time of the purchase, the bed frame was already ready and the rear seats were installed, so they fit into the salon only diagonally.

Next is the “brain” of the entire system. Epslar Tracer charge controller, made using MPPT technology.

Solar panels (they are 12 and 24 volts) cannot be connected directly to the terminals of the batteries. The reason is quite simple: the panel does not “know” the level of its charge, and in sunny weather it will try to download energy into an already fully charged battery, which leads to its rapid aging. So it is necessary to use the controller.

There are two types of controllers. The first is PWM, or ShIM controller (it uses the technology of wide-pulse modulation). They are simpler and cheaper in production. Briefly-a 12-volt panel in sunny weather issues an operating voltage of 14-15 volts, the controller partially uses it to charge the battery, and partially disperses the “extra” energy into heat. Once on Defender, he used the STECA SHIM controller, it heated significantly when the battery was almost charged.

In addition to the above, this technology has a significant drawback. In cloudy weather, the panel may not issue an operating voltage of 14-15 volts, which leads to the cessation of charging batteries, since “simple” shim controllers do not know how to increase the voltage obtained from the panels (only lower, partially scattering into heat).

MPPT controller is more complicated, more expensive, but more effective (it has a higher efficiency). But the most important thing: it allows you to connect the panels sequentially, thus raising their operating voltage from 12 to 24/36/48 volts, which leads to a more efficient charge of batteries in cloudy weather, since the voltage from the panels from the panels will always be higher 12 volts. And, if I am not mistaken, increase low voltage with sufficient current strength, he also knows how.

How to choose the controller model you need for performance?

I have two panels with a rated capacity of 400 watts each, total 800 watts in total. Charge voltage for 12-volt batteries-14.8 volts. Divide 800 watts by 14.8 volts, we get the maximum current strength of 54 amperes (the current that should “digest” the controller when the panels operate at full power). So in this case we need a 60 ampere controller model (with a small margin, although in reality I will most likely never see such numbers, I will tell you a little later why).

So, the Epslar Tracer 6420an model. It is able to charge the batteries with an current of up to 60 amperes, automatically determines the voltage of the onboard network of the machine (12/24V), has a “tropical” performance (the fee is varnished and is not afraid of humidity). The maximum power of the connected solar batteries is visible on the label.

The controller has a small screen for displaying and setting up parameters. On the left below there is a fuse. Terminals are designed for wires with a cross section of up to 35kV.Mm, just such I paved from the battery under the passenger seat in the back of the cabin. The air temperature sensor is located to the bottom right, above it. Two RJ45 ports for connecting additional accessories, and several more conclusions, one of which is controlled using a relay according to the specified conditions. For example, on the street it got dark, the panels stopped giving voltage, you can automatically turn on the light in the cabin. Or vice versa, the sun has risen. You can turn on the electric heating of water in the tank.

Since this block will be installed without the possibility of accessing it, it additionally acquired an external screen for it (in the photo below on the right, black), which displays more statistics and allows you to configure all parameters.

Types of solar panels

Important: it will be about the panels that produce electricity. Solar panels are also called water heating elements operating from solar heat. These are completely different technologies, although the panels look like.

Regardless of the type of solar panel, the system is equipped with the following elements:

• Solar battery controller: an electronic device that controls the operating modes responsible for connecting security. Without it, the system will not work.
• The battery (or a whole battery of batteries): is a kind of buffer that ensures the continuity of electricity supply, for example, at night. You can use a solar power plant without it.
• DC converter into alternating current, simultaneously increasing the voltage to the required 220 volts. If you do not have alternating current consumers, you can do without this device.

Having decided on the composition of the home power plant, we choose which panel to use. With the exception of innovative models that are under development, three types are available for the consumer:

• Monocrystalline. The plates are “sawed” from a single silicon crystal. Have a high efficiency (up to 22 %), and a long service life. The warranty of most manufacturers is at least 25 years. Practically does not change the characteristics during the entire service life. Relatively high cost in comparison with analogues. Due to the high efficiency, the smaller coverage area is required: the installation is simplified accordingly. A characteristic shape of cells is a square with beveled angles.
• Polycrystalline. Crystals are randomly located, but the cultivation process is significantly cheaper. The efficiency is lower than that of single.Crystals: about 18 %. They work worse with weak light (cloudy weather). Have high strength, are not affected by temperature differences. Production is inexpensive, which favorably affects the final cost. To obtain similar power, you will need a large area of ​​batteries, in comparison with single.Zeroles. Plates occupy the entire surface area, without bevels and gaps.Mono and polycrystalline panels are installed only in ready.Made protective blocks. As a rule, the assembly is carried out at the factory.
• Amonia thin.Film panels have been developed relatively recently. These are artificially grown flexible constructions that have practically no restrictions on the installation method. The main advantage of this type is flexibility and the ability to integrate into the finishing elements of buildings. Outwardly the panels resemble tinted glass, they can be installed as decor elements.The efficiency is quite low, up to 12 %, but the amonia panels work even with weak illumination. The cost is the same as that of crystals, but for similar power it will require a large coating area. Strength does not depend on temperature, do not lose efficiency when heated.

Installation nuances

With any of the selected types of installation, it is necessary to monitor the angle of inclination. In the case of the farm, you can set any degree of inclination, as well as orientation to the north or south.

With installation on the roof, these regulatory functions disappear, you will not rebuild the roof to comply with the desired angle of inclination.

Be sure to consider the moment of shading of the batteries to each other. If on the roof you put them on one plane, then on farms some use several levels.

In this case, the distance should be taken into account to exclude shading. This distance is 1.7 from the height of the farm.

Expert Council: For more efficient use of existing space, it is recommended to combine the types of arrangement of solar panels. Fasten the panels on the roof of the house and on special ground farms.

The result of the work done will be the fact of the appearance of a solar battery in your area, depending on the material and area of ​​which you can receive a different amount of electricity.

Having installed on your own for the first time at home, in the future you can offer this service to others, and taking into account the fact that the growth of sales of solar panels is currently noticed, this can bring an additional “penny” to your

Watch a video in which the stages of installation of solar panels are shown in detail: