Contents
Today we will talk about how to choose a solar panel for your home and get free solar electricity.
Energy sources
Energy sources taken from the environment are becoming more and more relevant.
Water, wind and sun are almost endless sources that can provide almost inexhaustible energy. It remains only to convert it into electricity.
Moreover, these sources are available not only on an industrial scale, they can also be used by a simple layman.
The most optimal for the owner of a house or cottage is the use of solar energy.
After all, rivers are not everywhere, there are also areas where there is not so much wind, but daylight is able to provide electricity almost anywhere in the world.
Of course, it will not always be possible to fully provide electricity to all appliances in the house at the expense of solar energy, but some of them are quite possible.
The amount of electricity generated depends on many factors: the area of solar panels, the material of their manufacture, features of additional equipment, weather conditions.
Solar panel design
First, let’s deal with the solar panels themselves. These panels are a module that converts solar energy into electrical energy.
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They are made in the form of rectangles with a small thickness. This allows you to mount them on any straight surface – the walls of the house, the roof.
The design of classic modules, which are now the most common, is as follows: there is a module frame made of anodized aluminum profile.
Inside this core are cells with semiconductor wafers, consisting of crystalline silicon. All cells are interconnected by wiring.
From the front side, to prevent damage to the cells, they are covered with tempered glass.
On top of this glass, as well as on the back side, a laminating film is applied, which makes the module hermetic and prevents moisture from penetrating inside.
The electricity generated by each cell is transmitted through wires to a distribution diode box, from which it already goes further.
The module is considered standard with 36 cells, each of which generates 0,5 B. Modules are also available for 72 cells that provide output from the diode box 24 AT.
Types of solar panels
As for the cells, they are of two types – monocrystalline and polycrystalline. They differ in the material of manufacture, shape, efficiency of energy conversion.
In single-crystal cells, silicon crystals of uniform structure are used during creation.
In the second type of cells, silicon crystals with different structures are used.
The structure of the crystals affects the overall energy conversion efficiency.
It is higher for single-crystals, so a module with such cells is able to provide the same amount of energy production as a polycrystalline module, but with a much smaller size of the panel itself. But the cost of monocrystalline panels is higher.
In appearance, these modules are easy to distinguish. Monocrystalline panels have rounded cell corners.
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The cells of the polycrystalline module has a rectangular shape.
Recently, modules have appeared whose cells are made of amorphous or micromorphic silicon.
Such modules do not have a frame, and they are made in the form of a film that is glued to the surface. It should be noted that such modules are the cheapest due to the lower silicon consumption.
Other elements of the system
But panels alone are not enough. The energy generated by them must be properly redistributed. The controller is responsible for this. All the energy generated by the panels goes to it.
It should also be noted that the panels generate low voltage direct current, as already noted, one panel can provide 18 or 24 Q. And most household electrical appliances are mains powered 220 V and AC.
Therefore, in order to be able to use the electricity generated by the panels, an inverter is required, which will convert it.
If solar panels are designed to be used as an autonomous system to provide electricity, then energy storage devices will be required, because the panels will not generate energy at night.
These storage devices are batteries.
Panel selection
Next, consider what you should pay attention to when choosing solar panels and other equipment that is necessary for the entire system to function.
First, you should decide what total power of electricity should be generated by the panels. For this, the average daily energy consumption is calculated.
Then it is determined how much power one panel provides per daylight hours.
Further, it is simply determined how many panels are required to generate the energy that is consumed per day. This is in the case of a complete transition to autonomous power supply.
Based on this, the modules are already selected. If the area for their installation is not so much, then it would be better to purchase single-crystal modules.
Although they are more expensive, the area of uXNUMXbuXNUMXbeach panel is smaller than polycrystalline, and its service life is longer.
It is better to purchase panels from well-known manufacturers, for which they give a long warranty period.
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Controllers
Let’s move on to charge controllers. The generated energy passes through them and is fed to the batteries.
Two types of controllers are currently being produced – pulse-width modulation (PWM controller) and maximum power point tracking (MPPT controller).
PWM controllers more simple and accessible.
However, when using them, up to 30 % generated by the panels.
MPPT controller is capable of producing 100% energy production, but its cost is much higher.
For example, the output power of the panels is 2 kW. When using a PWM controller, due to generation losses, the final power will be 1400-1600 W. But the MPPT controller is able to process everything 2 kW power.
Therefore, it is recommended to use an MPPT controller when installing panels with an output power of more than 1 kW.
As for power indicators, the controller is selected according to the power that it is able to process.
Battery
As for batteries, acid batteries are the most affordable now. The main parameter in the selection is the capacity, the larger the battery, the better.
There are certain formulas for calculating the capacity of a battery, which determine what it should be in order to power all the necessary electrical appliances.
If this system will not be used autonomously, without energy storage and is aimed only at saving, then the installation of a controller and batteries is not needed.
In such a system, the generated energy goes directly to the inverter, and then it is already consumed by consumers.
Инвертор
Inverters are available in three types – autonomous, network and combined.
Autonomous inverters are used in the full transition to the use of solar energy, where energy is stored in the battery and its simultaneous consumption.
The grid inverter is used in systems that do not store energy. It immediately converts the electricity supplied to it from the panels and feeds the consumers. It connects to the general network of the house.
Combined inverters can work both as an autonomous and as a network, and with a choice of the priority of the energy source.
The main parameter of the inverter when choosing is its power.
To correctly determine its power, the power of all electrical appliances that can be turned on at the same time is calculated and added to the total power 20%. This will prevent the inverter from operating at maximum loads.
When using a network inverter, its power is selected according to the output power of the solar panels, since it will interact with them directly.
By following these recommendations, you will be able to choose the right solar panel for your home. And the installation of solar panels is still entrusted to specialists.