Solar panels are considered a very efficient and environmentally friendly source of electricity. In recent decades, this technology has been gaining popularity around the world, motivating many people to switch to cheap renewable energy. The task of this device is to convert the energy of light rays into electric current, which can be used to power a variety of household and industrial devices.
The governments of many countries are allocating enormous amounts of budgetary funds, sponsoring projects that are aimed at developing solar power plants. Some cities make full use of electricity obtained from the sun. It is worth noting that the principle of operation of solar panels for homes is quite complex. Next, let’s consider in detail how solar panels for the house work.
Principle of operation
As mentioned before, the principle of operation is the effect of semiconductors. Silicon is one of the most efficient semiconductors known to mankind at the moment. When the photocell (the upper silicon plate of the transducer block) is heated, electrons are released from the silicon atoms, after which they are captured by the atoms of the lower plate. According to the laws of physics, the electrons tend to return to their original position. Accordingly, from the bottom plate, the electrons move along the conductors (connecting wires), giving their energy to charge the batteries and return to the top plate.
The design of a solar panel is very simple.
The basis of the construction of the device consists of:
- the body of the panel;
- conversion units;
- additional devices.
The casing has only the function of holding the structure together, with no other practical use. The main elements are the converter blocks. This is the photovoltaic cell, which consists of a semiconductor material, which is silicon. We can say that solar cells, whose design and principle of operation are always the same, consist of a framework and two thin layers of silicon, which can be applied to the surface, both monocrystalline and polycrystalline.
The method of silicon deposition determines the cost of the battery as well as its efficiency. If the silicon is applied in a monocrystalline way, the efficiency of the battery will be as high as the cost.
If we talk about how a solar battery works, we should not forget about the batteries. As a rule of thumb, two batteries are used. One is the main one, the second one is a backup. The main one stores electricity, immediately directing it to the electric grid. The second accumulates excess electricity, then sends it to the grid when the voltage drops.
Additional devices include controllers, which are responsible for the distribution of electricity in the network and between the batteries. As a rule, they work on the principle of a simple rheostat.
Very important elements of solar are diodes. This element is installed on every fourth part of the inverter unit, protecting the structure from overheating due to excessive voltage. If diodes are not installed, there is a good chance that after the first rain the system will fail.
How to connect
As mentioned earlier, the design of a solar panel is quite complex. The right solar panel circuit will help to achieve maximum efficiency. It is necessary to connect the inverter units using a parallel-serial method, which will provide optimal power and the most efficient voltage in the electrical grid
How to maximize efficiency
When buying solar panels for your home, it is very important to choose a design that can provide your home with electricity of sufficient power. It is believed that the efficiency of solar panels in cloudy weather is approximately 40 watts per 1 square meter per hour. In fact, in cloudy weather the power of light at ground level is about 200 watts per square meter, but 40% of sunlight is infrared radiation, to which solar panels are not susceptible. It is also worth bearing in mind that the efficiency of the battery rarely exceeds 25%.
Sometimes the energy from intense sunlight can reach 500 watts per square meter, but when calculating, it is worth considering the minimum values, which will make the autonomous power supply system uninterrupted.
Every day the sun shines for an average of 9 hours, taking the annual average. In one day, a square meter of the surface of the converter is able to generate 1 kilowatt of electricity. If about 20 kilowatts of electricity are consumed per day by the inhabitants of the house, the minimum area of the solar panels must be about 40 square meters.
However, such a figure of electricity consumption in practice is rare. As a rule, tenants will use up to 10 kW per day.
If we talk about whether solar panels work in the winter, it is worth remembering that this time of year greatly reduces the length of daylight hours, but if you provide a system of powerful batteries, the energy received for the day should be enough, taking into account the presence of the battery backup.
When selecting a solar panel, it is very important to pay attention to the capacity of the batteries. If you need solar panels working at night, the capacity of the backup battery plays a key role. Also, the device should be resistant to frequent recharging.