Solar panels installation and installation. Use of collectors and solar panels in the heating of the house.
It is hardly possible to imagine comfortable living conditions for a modern person without heating and air conditioning systems, household appliances (a refrigerator, a kettle, a microwave oven), a television set and a computer working on electric power.
In a private house, in addition to the devices listed, a person needs pump for water supply , septic tank, burglar alarm, boiler heating system and much more. Electric energy has become an integral part of our life and its meaning can be understood only in the absence of it.
Unfortunately, in our country there are quite a few houses and whole settlements not connected to the electrical networks. And territorially these settlements are not in the taiga or in the tundra, but in the center of the country, in the suburbs. However, there are many houses without electricity in other parts of the country.
To ensure a minimum level of comfort, it is necessary to generate electrical energy independently, using for this purpose generators, solar panels or wind generators.
In the suburbs wind generators are not effective, here is the low average annual wind speed, which makes their installation useless. Preference is given to solar batteries and traditional generators for liquid fuels.
Selection of solar panels
Modern solar panels are effective at any time of the year. A prerequisite for their work is the presence of a clear cloudless sky and direct sun exposure to the surface. In cloudy weather, the generation of electricity also does not stop, but the productivity of solar batteries is sharply reduced.
In order that the obtained electric Energy could be used by the consumer, together with solar batteries, it is necessary to purchase batteries and an inverter. Such a package can be called a solar power plant. With its help you can not only receive electricity, but also accumulate it and use it as needed. The equipment is selected depending on the needs of the consumer and on what kind of electrical devices will continue to work at the expense of the received electrical energy.
It should be noted that at present the cost of a unit of energy produced with the help of solar panels is not cheap, an average of 25 rubles per 1 kW, which is about five times more expensive than electric power in centralized electric networks.
Therefore, to talk about the installation of solar panels in order to save money to pay for energy resources at the moment does not make sense. However, in the future, with a decrease in the cost of equipment, getting electricity with the help of the sun will certainly be much cheaper. But so far this is a matter of the future.
How to choose the equipment?
Selection of equipment for installing solar panels in a private home begins with the definition of a list of electrical appliances, the use of which is planned in the future. This list is then carefully analyzed to find an alternative to each electrical appliance. For example, an electric kettle can be replaced by heating water on a gas burner running on liquefied fuel, water for household needs and a shower heated with solar collectors , and without lighting, security alarm and volatile system of automatic control over the operation of the gas boiler will not be manageable.
Leaving in the list only the necessary minimum, calculate the need for electrical energy and then select solar batteries of appropriate power.
How much does a set of solar panels for the house
- Solar panels
The main element of the solar power plant is the solar module or solar panel. Panels are:
- on the basis of single-crystal silicon elements
- based on polycrystalline silicon elements
The cost of solar panels depends on their size and technical specifications and is in the range from 1500 to 16000 rubles. So, for example, a panel of 1650 x 991 x 40 mm costs more 16 thousand rubles, and with its help you can get 200-260 watts of electricity. To create comfortable conditions in the country there are enough 4 such panels, for a house with a permanent residence they will need twice as much.
The service life of solar panels on the assurances of manufacturers is at least 25 years.
- Inverter
The second inalienable element of the solar power plant is the inverter. The cost of 2-2.5 kW inverters is in the range from 17 to 25 thousand rubles.
- Rechargeable batteries
Batteries can be called a "bottleneck" of a solar power plant. Manufacturers claim the battery life of 10 years, stipulating the number of cycles of the full discharge, after having worked out the battery is unusable much faster.
In fact, in the country house battery battery will have to be changed after 3-4 years of operation. The cost of a battery for a solar power plant is in the interval from 12 to 27 thousand rubles. For a comfortable stay, one battery is not enough. As a rule, batteries are set to 2 or even 3.
As a result, a solar power plant for a summer residence costs an average of 100 thousand rubles, not counting the costs of installation of equipment. With its help, you can get 1 kW of energy per hour and use it at your discretion. This is sufficient for the operation of the refrigerator, TV, lighting with energy-saving lamps and ensuring the uninterrupted operation of the heating boiler.
After 3-4 years of operation, the batteries will have to be replaced. This period may be shorter or longer, it all depends on the cycles of the complete discharge of the batteries.
What is more profitable - a generator or solar panels
The cost of a solar power plant exceeds the cost of an equal in capacity to a liquid-fuel generator. But to get electricity with solar panels no additional costs other than the cost of purchasing equipment, it is not necessary.
For the generator to work, you need fuel, the cost of which can not be called low. With an approximate calculation, the cost of one Watt of electricity received by the sun is 1.8 times lower than the cost of a unit of electrical energy obtained by burning liquid fuel.
When and where should I use the batteries?
Installation of solar panels is necessary where there is no possibility of connection to electric networks. Choosing between a generator and a solar power plant, preference should be given to the latter.
The installation of a solar power plant will not solve all the issues of electricity supply. So, for example, it is unlikely that anyone will afford to heat a house with the help of the received electricity, but it is available for everyone to ensure the uninterrupted operation of the gas boiler on LPG.
To date, the installation of solar panels in a private house is not a way to save or save energy, but the opportunity to live in comfort in the absence of a centralized supply of electricity.
Once the reasoning that electricity would be free seemed to be fantastic inventions. But the time passed and the development of new technologies in the electric power industry led to the fact that this became a reality.
Alternative sources of energy are winning more and more supporters around the world.
Among them, solar batteries are very popular, widely used both in production and in everyday life.
Application area
Solar panels, or as they are sometimes called solar panels can be used to provide cottage villages, summer cottages, industrial enterprises.
They are very effective for sanatorium complexes, hotels, hospitals, buildings located far from the main power lines.
We can say that they are needed where there is a need for one more source of energy and where there is an opportunity to establish them. At the moment, solar panels are equipped with roofs of buildings, houses, install them in deserts and on trains. Existing even completely autonomous houses on solar batteries.
The production of solar batteries is going at a huge pace and the leaders in this industry are the PRC, the USA. Germany, the countries of the Persian Gulf, Western Europe and Scandinavia.
What is a solar battery?
This is a complex of photoelectric converters combined into a system. Transformers convert the energy of the Sun into electricity. The latest solar cells are able to work with a 40% return. To achieve this, it is necessary to observe certain parameters.
Battery complexes are most advantageous to mount in those points on the planet where the number of sunny and clear days is predominant, in Russia these are the southern regions of Krasnodar Territory, Sochi and others.
It is necessary to take into account the geographical breadth on which the buildings are located. Approaching the poles, solar energy is losing some of the power and efficiency of solar cells will be inadequate.
If in winter, where battery systems are installed, there are enough cloudless days, they can significantly reduce the load on the municipal utilities and provide some of the buildings with free energy.
Types of solar cells
Types of solar cells
Now they are classified into 3 categories:
- Thin-film
- Monocrystalline.
- Polycrystalline.
Thin-film batteries
This battery complex is made of thin stretched films. They are easily mounted in almost all available locations.
Protected against sand and dust and able to function in a variety of adverse conditions. In the presence of clouds, their efficiency is reduced by about twenty percent. Their cost is small, but they require a considerable space for their placement.
Monocrystalline batteries
These batteries create a multitude of cells, which are then filled with silicone. Because of the good battery data are applied even on ships.
They can be placed on buildings. If there is no possibility to install them on the sunny side of the roof, where, of course, the return from them will be higher, it can also be installed on the shady side. It must also be taken into account that the scattered sunlight will be less effective.
Monocrystalline batteries are small in weight, compact. They are flexible enough, reliable in operation and serve for a long time. Installation of such batteries does not cause difficulties.
But they have a drawback. In the absence of sunlight and clouds, they cease to produce electrical energy.
Polycrystalline solar cells
In the cells of these solar batteries are located crystals, directed in all different directions.
Thanks to this, the panels can catch scattered light, and much less depend on direct sunlight.
They are familiar to very many thanks to illustrations in magazines and on the Internet. Companies produce such batteries in the form of blue panels, which look very impressive and stylish after installation. They cost a little cheaper and can be installed in many places. They can illuminate the streets of cities, homes, institutions. 
Why choose solar panels?
There may be a question - why solar cells, and not any other sources of energy?
- While the sun is shining, solar panels will also generate electricity.
- Such batteries are autonomous. They do not need centralized power systems for connection. Therefore, you can sharply on the maintenance of infrastructure in cities, enterprises and housing stock. The power of local energy companies is reduced to almost zero. Energy independence is acquired.
- In remote areas and towns laying the cable will cost a lot of money. It will be much more profitable to install solar panels. The costs will be minimal and there is no need to pay for the services of a whole team of installers - electricians.
- Ecological compatibility. The main advantage of these batteries. There is no need to use expensive, and, moreover, irrecoverable fossil resources. Photocells do not emit carcinogens, and do not increase the amount of carbon dioxide in the planet's atmosphere. There is no need to cut down huge areas of forests and so affected by human activities.
- Lack of licensing. The regulations requiring licensing of receiving electricity through such batteries have not yet been put into effect. Therefore, this factor should be used until another duty is introduced.
Can I use solar panels in the private sector?
Solar cells have long been used successfully by corporations and companies, as well as by owners of their homes. Prices for such products in Russia are still lower than those of Western models. As for quality, this is another question. Nevertheless, the cost of products with the introduction of new technologies is gradually decreasing and solar batteries are becoming available to an ever wider category of consumers. Manufacturers of solar panels for the home offer their customers with a lifespan of at least 25 years.
How beneficial is it to install solar panels by yourself for a private house?
Installation diagram
It is necessary to calculate how many sunny days usually there where the consumer lives. After that it will be necessary to divide the cost of the equipment by 25 years and the counted sunny days in a year.
Then it will be possible to calculate whether it is worthwhile to install solar panels for the house. You will also need to calculate the area needed to get 1 kW of electricity in your region of residence.
All these data are provided by the manager who sells solar panels. In addition, the period of the greatest solar activity should be taken into account.
Receiving hot water with batteries
The next question that needs to be solved, and for what purpose, you need electricity from solar panels. Usually it is necessary for:
- Lighting.
- Getting hot water and heating.
- Work of household appliances.
To supply hot water, you can install a solar collector.
It is inexpensive, and you can make it yourself. It can function in autumn and winter. In their homes have long been used to heat water tanks, functioning from the energy of the sun
Lighting the house with solar panels is also a challenge at the moment.
Accumulators in the back room of the house
It is important to take into account such an important point as the replacement of battery batteries. Knowing how much ordinary batteries for cars cost, it will be possible to calculate the cost of maintenance of batteries for solar batteries. In addition, it is necessary to regularly clean the surfaces of the batteries from dust. How much solar cells are needed for a home, it is necessary to decide on the basis of the area of the house and the purposes of using batteries.
Thus, a set of solar panels for a house can cost as fairly inexpensive, and cost a round sum.
But the technology is developing faster and solar batteries for the home will be cheaper, and will be available to very many consumers.
Installing solar panels yourself is easy, you just need to attach batteries to the controller, which will transfer the charge to the batteries and use the inverter to transfer electricity to your home. Successful electricity!
Looking at the ocean of energy pouring from heaven to earth, we remain dependent on the electricity.
If in the city the supply of current is more or less stable, then outside the city the residents regularly become participants in the "end of the world".
How to provide your home with a reliable source of electricity and not deprive yourself of comfort, impossible without "directed movement of electrons"? The answer is fairly simple in theory, but almost unfamiliar to many in practice.
These are solar panels for a private home they are the main condition for an autonomous existence.
What are these devices, their types, characteristics and efficiency of application we will consider in this article.
Types of solar cells
From the school course of physics we are familiar with the photoelectric effect. It occurs in semiconductors under the action of light. All solar panels work on this principle.
We will not go into the theory of the process, but only the most important practical points:
- There are three types of solar cells: monocrystalline and polycrystalline and amorphous silicon panels (flexible).
- All of them produce a direct current (voltage 12 or 24 V).
- The service life of these devices is more than 20 years.
- A powerful battery can not work effectively without additional equipment (controller, battery, inverter).
Now go through the details for each item. A single crystal panel, compared to a polycrystalline panel, produces a higher power per unit of surface. At the same time, the price is much higher.
The performance of a polycrystalline cell is 15-20% smaller, but it does not significantly decrease with cloudy weather. In a monocrystal, on the other hand, in the case of diffuse illumination, the production of electricity sharply decreases. The solar battery of amorphous silicon is cheaper than polycrystalline silicon, but its service life is 2-3 times less. Based on these facts, it is more profitable to buy polycrystalline panels.
A set of equipment for a solar station
A powerful solar battery for a summer residence - the device is not self-sufficient. The received energy needs somewhere to be stored up, that in the evening and in cloudy weather it is high-grade to use household electric appliances.
Therefore, a capacious and durable battery is in any case required. In his choice there is one important nuance: do not try to save by buying a starter car battery. It is poorly suited for cyclic energy storage and does not tolerate a deep discharge. Its main purpose is to give a powerful but short-time current for starting the engine.
To store and slowly consume energy you need batteries of a different type: AGM or gel. The first are cheaper, but have a short service life (up to 5 years). Gel batteries are more expensive, but they work much longer (8-10 years).
The controller is another important element of an autonomous solar power plant. It performs several tasks:
- Disconnects the battery from the battery at the time of full charge and turns it on for a new power download.
- Selects the optimal charging mode, increasing the amount of energy stored.
- Provides maximum battery life.
There are several types of controllers used in solar stations:
- ON / OFF "on / off";
- MPPT.
The cheapest device simply turns off the solar panel from the battery when the voltage at its terminals rises to the maximum level. Is not the best option, because at this point the battery is not yet fully charged.
A more expensive PWM controller acts smarter. After dialing the maximum voltage, it lowers it to the specified level and holds a couple of hours. This achieves a more complete level of energy storage.
Finally, the most intelligent MPPT-type controller maximizes the power of the solar panel in all modes of its operation. This allows you to store additional 10 to 30% of electricity in the battery.
Regardless of the type of semiconductor materials used (polycrystals, single crystals, amorphous silicon), the solar array device is a chain of serially connected cell modules. Each of them generates a small voltage (within 0.5 volts) and a weak current (tenths of an ampere). Working together, they "drain" the accumulated energy into a common channel and at the output of the battery we get a current of great power and constant voltage (12 or 24 volts).
Standard household electrical appliances are rated at 220 volts, so they will not work from the "constant". Conversion of DC to AC performs a separate inverter device. They complete the chain of equipment necessary for a solar battery.
Despite the relatively high starting cost of the components of the solar station, its operation is beneficial due to the large "life" resource of the main elements: the photocrystalline panel and the battery.
How much solar cells do I need for a house and a summer residence?
Here everything is simple. The buyer does not need to deal with the complex calculation of the power of the solar station and select batteries for it. This work has already been done by specialists of companies that manufacture and sell this equipment.
The consumer can only choose from the proposed series a complete set, based on their needs. As an example, consider several standard options that are presented on the sites of sellers (actual for 2016).
The solar station, built on one panel with a capacity of 250 watts, is designed for power supply to consumers listed in Table 1.
Table number 1 A set of consumers for a solar station with a capacity of 250 watts
Its approximate price consists of the cost of the devices specified in Table 2.
Table number 2 The cost of equipment for a 250-watt station
A solar station with a capacity of 500 watts is capable of providing electricity to a set of household appliances, indicated in Table 3.
Table №3 The energy potential of a 500 Watt heliostation
Its estimated cost (broken down by types and models of equipment) you will find in Table 4.
A 1000 Watt solar power station is capable of powering not only economical LED light bulbs, a TV, a laptop and a satellite dish. Simultaneously with them, it "pulls" a microwave, a water pump or a powerful electric stove (table number 5).
The basis of this heliostation is 4 solar panels with a capacity of 250 watts each. For the entire set of equipment (without the cost of installation, couplings and cable), you need to pay the amount indicated in table number 6
Table №6 Approximate cost of solar power plant equipment with a capacity of 1 kW
Studying the presented sets of equipment, it is easy to see that the cost of the inverter is comparable to the price of a solar battery. Therefore, some owners of solar stations prefer to do without an inverter converter. They buy household appliances for their home that are powered by a 12-volt DC. In addition to the high price, the inverter consumes about 10% of the energy received from the solar battery. Therefore, his exclusion from the chain of equipment gives a good economy.
Mounting Features
Installation of solar panels is a technically simple process, but very responsible. The area and weight of the powerful panels are large enough, so they need a reliable fastening with the help of guiding and special fasteners. In addition, the roof should provide for easy access to batteries for cleaning from dust and snow.
From the magnitude of the angle at which the sun's rays fall on the photocells, the energy production directly depends. Therefore, solar panels are not fixed in one position, but mounted on rotary devices.
There are two main positions of heliopanel: summer and winter. Changing the angle of inclination, from the solar station receive the maximum efficiency.
Characteristic feedback
They can be divided into two groups: reviews of those who already use these devices and the opinions of all those who are only studying the issue of autonomous power supply.
Most owners of solar stations are happy with their choice. Having equipped them with vacation home, they note the reliability, all-season effectiveness and efficiency of heliopanels. Reflecting on the purchase, they express doubts about economic feasibility, fearing long term recoupment of equipment.
We will express our thoughts on this topic. Taking into account the stable increase in the cost of electricity received from external networks, the use of heliostation can not be called unprofitable. If it is a question of areas where the power supply is completely absent or characterized by frequent outages, then the heliostation is not an option.
Self-assembly
To try their hand at solar power engineering of domestic craftsmen are prompted by two factors: the desire to reduce the cost of heliophenels and the novelty of this work.
The savings from self-assembly are impressive. The do-it-yourself kit, consisting of photocells and an assembly conductive tape, is almost 50% cheaper than the battery assembled at the factory. Buy it can be on the Russian trading Internet sites or order direct delivery from the country of origin.
Answers to the question of how to make a solar battery for the home with their own hands in the worldwide network can be found very much. In addition to the oral description of the process, here you can find intelligent videos that clearly demonstrate its main stages.
The practical advice contained in such manuals is based on an invaluable experience of trial and error. They help beginners without serious financial losses to successfully carry out this work.
The assembly of the solar battery includes the following steps:
- sequential soldering of photocells into a single energy chain with the help of conductive tape;
- making a frame with glass.
The most important moment is the filling of the photocells with a transparent sealant and their integration with the glazed frame. Here there is a proven technology, the basis of which is a thick sheet of foam rubber, which protects fragile photocells from destruction.
The main elements solar battery for private house is a photovoltaic panel (not to be confused with a panel of solar water heating) and an inverter. The photovoltaic panel converts the energy of solar radiation into direct current electrical energy.
The inverter converts the direct current electricity generated by the solar battery into AC power 230V, 50Hz. They are placed on the roof of the building, on the roof slopes directed to the south and connected in a row in such a way as to obtain a greater voltage. The inverter is best placed in a room in which the main switchboard is installed with automatic switches, can also be in another room or on the outside wall of the building.
The amount of electricity generated solar batteries depends on the intensity of the solar radiation incident on them, the time of lighting the battery by the sun and the correct installation of the panels.
What you need to know before deciding to install a solar battery in a private house?
You should make sure that the plane of the roof on which we want to install the system is directed to the south, and also that it is not in the zone of the shadow cast by other structures, chimneys, with trees.
Avoid shading of photovoltaic panels. Check that the roof has a large enough area on which you can mount solar panels. So for a power of 1 kW, 8-10 m2 of free surface is required.
The most frequently asked questions about the installation of solar panels for a private house:
What factors affect the efficiency of solar cells?
Orientation of the roof - under optimal conditions, the modules should be oriented to the south. If this is impossible by 100%, then the principle operates: the closer to the southern direction, the higher the productivity of the photovoltaic system;
- roof slope - the generation of electricity by the battery will be greatest when the sun falls on the solar cells at a right angle. Optimum angle of inclination for photovoltaic panels for temperate latitudes is in the range 30-40 °;
- shading - architectural and natural factors leading to the formation of shadows falling on a solar battery, lead to a reduction in the amount of electricity produced, and you should avoid them;
- installation execution - an incorrectly designed or manufactured installation, may be the cause of performance degradation or irreversible damage.
Where is the solar battery connection point for a private house, for electricity meter or in front of it?
We connect the output from the inverter behind the meter, at any point in the internal wiring in the house, or even better - immediately after the electricity meter, so that the generated electrical energy will also feed the electric receivers in the household buildings.
Solar panels produce power in a single-phase or three-phase version?
The recommended power produced by photovoltaic installations designed to supply a private house should not exceed 5 kW, so this equipment is single-phase. For power over 5 kW, installations with a three-phase system are used.
In the event of a power failure in the supply network, can the solar battery represent a backup power source of the building?
No. With the disappearance of the voltage in the network that feeds the building, solar installation is turned off. The reclosing occurs automatically when the mains voltage appears. There is, of course, the possibility of expanding its functions by installing a battery. Then, in the event of a voltage failure in the mains, a switchover to a backup power source takes place, which can be used until the battery is discharged. This solution is, however, associated with a significant increase in the cost of the installation.
When does a photovoltaic solar cell not produce electricity?
At night, very strong clouds and fog, completely covered with snow photovoltaic panels, with no voltage in the building network.
Do snowfalls disrupt the installation?
The passage of current through solar panels during operation causes heating of their surface, as a result of which melting of snow on the panels occurs and restoration of normal conditions for the operation of the plant.
How does the outdoor temperature affect the operation of the unit?
Photovoltaic panels have a negative temperature coefficient. This means that the lower the ambient temperature, the greater the output voltage and the higher output power.
What is the durability of the photovoltaic system?
Unlike other generating sources of electricity, solar cells do not have moving elements, which is the decisive factor for their durability. Manufacturers of photovoltaic panels guarantee a decrease in their productivity after 25 years of operation, no more than 15%.
What should be guided when buying your own photovoltaic system?
The decisive condition for the purchase of the installation is the right choice of the company that offers the sale and installation of the installation. It should not be forgotten that about 70% of the products come from China. Companies that declare the production of panels in Europe, miss the fact that in most cases, the installation is performed using imported silicon elements from China. The most important element of the battery is the inverter, which is mainly manufactured in Germany. It is also important to design, carefully and correctly select the remaining components of the installation, since it is supposed to work for at least 25 years.
How long does it take to install and incorporate solar panels in a private house?
Complete installation of the system for a private house and its loading usually take 2-3 days. It is necessary to prepare the corresponding installation project in advance and sometimes wait several days for the delivery of the relevant components.
What happens to the excess of electricity produced?
The electric energy generated by solar batteries should be used first of all in the house. In case of surplus produced energy, it must be used for own needs, and not to sell (the cost of one kWh is very high and no one will buy it). This energy is directed to additional consumers, such as an electric boiler for heating water, air conditioning or other devices. So, for example, in a house with solar panels on a nice sunny winter day, surplus electricity is able to heat about 150 liters of water from 10 ° C to 60 ° C.
Can the photovoltaic system replace the installation of solar water heating?
Yes, of course, there are many arguments in favor of such a decision, and especially if we are planning to build a new house, cottage or villa. Do not install equipment with outdated and less efficient technology. The main argument here is a great profit and economic feasibility.
With the same financial costs for installation, we get about 50% more energy, and this is electrical energy, which we can use in any form, including for heating domestic water or powering the air conditioner in the summer.
The second undeniable argument of such a decision is the negative temperature coefficient expressing physical properties a photocell of silicon, which leads to the fact that the productivity of the photovoltaic system is greater the lower the ambient temperature, this gives a certain advantage in the winter period over the installation of solar water heating.
How do solar panels work for a private house in case of using additional water heating for domestic needs?
Renewable energy sources (RES) are unpredictable and depend on natural changes, therefore they can not be considered as the main source of nutrition. Therefore, solar batteries should be considered as an auxiliary source for the preparation of hot water for household purposes. Water will be heated in the case when the energy produced by the plant meets the demand of all domestic receivers included (this is a priority) and there is an excess of energy. If this surplus of electricity is not used, then it will go to the grid of the power supply company (note that your electricity meter will not spin in reverse side since it is equipped with a brake).
Thanks to the use of a special filter, this excess can be sent to an electric water heater or other receiver. A properly designed and manufactured solar battery for a private house is able to provide up to 50% of the energy consumed.
The use of a special energy filter to use its excess and direction for heating water, space heating, air conditioning, allows using up to 80% of the generated energy.
The main advantages of using solar panels in a private house:
Reduction of the payment for electricity;
- battery operation even in cloudy conditions, using scattered sunlight;
- the greatest production of energy occurs at the same time that the peaks of electricity demand in the economy (the zone with the greatest cost of kWh of electricity) and here there is the possibility of additional savings;
- the modular nature of the installation allows it to increase its capacity and at the same time regulate the size of the investment;
- protection of the environment and the surrounding environment, since solar panels in a private house do not emit CO2 and noise at all, they do not have moving parts;
no need for maintenance - the unit is designed for automatic work for at least 25 years;
- Reliability - 5 years of equipment warranty and 25 years of performance guarantee ensure peace of mind and confidence in the correctness and appropriateness of financial investments.
Over the past 10 years, houses with solar panels on the roofs have gone from curiosity to the usual phenomenon.
This technology has been available for decades - cosmonauts have been using solar-powered satellites since 1960, and in the second world, passive solar heating systems (which convert solar energy into heat instead of electricity) have been used in US homes.
True, the introduction of active solar systems as a commodity of wide consumption proved to be a problem. Active solar energy uses panels of photovoltaic cells to convert sunlight into electricity, and this has traditionally been an exorbitantly expensive technology.
Advantages of apartment houses on solar energy are obvious:
- the energy of the sun is infinite (at least for the next 5 billion years, plus or minus),
- provides clean energy,
- without emissions of greenhouse gases, and this can save people's money on their electrical bills.
In this article, we will look at the six most important issues that need to be addressed when you are thinking about investing in installing solar panels. The use of photovoltaic energy is a very green solution and a potentially useful step, but it's not quite as simple as getting your energy from a regular electrical grid.
The first factor is the one you probably did not think about:
1. Service
The inclusion of your home in the use of solar energy requires more care than using a conventional old electrical network. But not much.
Solar panels do not have moving parts. They are part of the full stationary system. Therefore, once they are installed, there are not so many reasons that can go wrong. Almost the only thing a homeowner must do is keep clean panels. This is an important task, because - too much snow, dust and bird droppings on the panels can reduce the amount of sunlight. The accumulation of dust on the screen can reduce the amount of electricity produced by the system by as much as 7 percent. 
This type of service does not need to be done once a week, however. It is enough to water the panels from the hose one to four times a year. For this, you do not need to climb the roof. A hose with a nozzle from the ground works perfectly. If there is construction in your area, it is necessary to clean the panels more often to avoid additional accumulation of building residue dust.
In addition, from time to time, check that all parts are in working order. In addition, you need to replace the batteries, but this once in a decade.
2. Neighborhoods
The location of your home has a big impact on your solar energy efficiency. This is an obvious problem: If your electric power depends on sunlight, things like shadows of tall trees and tall buildings will be a problem.
This is a bigger problem than some people understand. Different types of panels-react differently to the shadow. While polycrystalline panels can significantly reduce the power output, any part of the shading of the mono-crystalline panel will stop the production of electricity completely. 
So, to build on solar panels, you need to make sure that there is no shadow on the panel over the roof area during sunny hours per day (usually from 10 am to 2 pm) and preferably during all sunny hours. The more hours the panels are exposed to full sunlight, the more efficient the production of electricity.
Achieving the greatest efficiency can mean cutting or complete removal of trees on your site. If your house is surrounded by tall buildings that block the sun from the roof, this is a much bigger problem.
3. Insolation
Sunlight obviously plays a key role when it comes to solar energy, and not all regions have equal conditions in this regard. It is important to know how much sunlight reaches the ground in the area where your potential solar home is located.
What we are talking about here is called insolation - a measure of how much solar radiation will fall on the earth in a particular area in a certain period of time. This is usually measured in kW / m2 / day, and it will show you how much sunlight will be available for your solar cells to turn into electricity. The higher the insolation value in your region, the more electricity each of your panels can generate. A high insolation value means that you can get more energy from smaller panels. A low insolation value means that you could end up spending more to achieve the same output power. 
So you must build your solar-powered house in the south-west, not in the north-west?
Not at all. This simply means that you will probably need more panels to achieve the same output power.
4. Coverage area
Contrary to what most people think, the size of a solar power plant has nothing to do with the size of the house.
Instead, only two parameters should be considered:
- insolation, which we have just discussed,
- how much energy you need.
The average house uses about 900 kWh per month, or about 30 kWh per day. Multiply that by 0.25. We get 7.5, so we need 7.5 kW of system.
A typical solar panel generates up to 120 watts, or 0.12 kW per day. To provide 7.5 kW, you need about 62 panels. One panel can be approximately 142 by 64 centimeters, so the 62-panel will occupy about 65 square meters.
You should also take into account the insolation and how many hours the peak of sunlight you get per day, and also make adjustments if you use batteries with panels. Therefore, it is best to contact the pros.
5. Costs
In 1956, solar panels cost about $ 300 per watt. A system of 7.5 kW could only afford very rich.Today, prices have fallen significantly. In most areas, solar panels operate about $ 3-5 per watt. You will pay closer to $ 3 if you install it yourself, and closer to $ 5, if you have professionals to do this. For 7.5-kW or 7500-watt panels, you could pay $ 22,500 to $ 37,500.
If you need less electricity, of course, the number becomes lower. If you only consume 600 kWh per month, or 20 kW / day, you could install a system with a capacity of up to 5 kW. Which will cost closer to $ 15,000.
Of course, it is partly to partially provide the house with solar energy. If you want to invest in solar panels $ 10,000, you can supplement the electricity from the grid with a 1.5-kW solar system.
Nevertheless, tens of thousands of dollars for solar panels are still quite exorbitant costs - especially since it can take decades until this money breaks back.
Although in the west they already practice renting solar batteries. There are no down payments. Homeowners pay a monthly rent for the use of panels, and the rental company owns them and supports them.
6. Disposal
The service life of solar panels 40-50 years, controller and inverter 15-20 years, batteries, depending on the type and nature of use - 4-10 years.
Although the issue of recycling solar panels remains open, only 30% of all manufacturers take them back for recycling.
But nevertheless, the demand for used solar panels grows every year. Since the mining of rare metals is becoming an increasingly expensive pleasure and the panels will lead to their reuse.
In addition: there is a secondary market for photovoltaic and wind power plants, on which already used equipment can find further use.
In countries with transitional economies, the already used solar modules can be used. Due to more intense solar radiation, these modules can generate more electricity.
An example of trade can serve as SecondSol - an online platform for the sale and purchase of used modules.
