How to construct and operate solar panels

Solar energy is becoming more and more popular all over the world. Together with colleagues from the specialized portal Elektrik we understand how to construct a solar panel, what it is and where to get energy. Nowadays almost everyone can gather and get their hands on an independent source of electricity is solar powered (in the scientific literature they are called photovoltaic panels).

Expensive equipment kompensiruet the opportunity to get free electricity. It is important that the solar battery is a clean energy source. In recent years the price of photovoltaic panels fell dozens of times and they continue to fall, which speaks about the great prospects of their use.

In the classic form of this source of electricity will consist of the following parts:

  • directly, the solar panels (DC generator),
  • battery monitor charge
  • inverter, which converts DC to AC.

Solar panels consist of solar cells (photovoltaic converters), which directly convert solar energy into electrical energy.

Most solar cells are made from silicon, which has a fairly high cost. This fact will determine the cost of electrical energy, which is obtained using solar panels.

Common two types of photovoltaic converters: made of monocrystalline and polycrystalline silicon. They differ in production technology. First have an efficiency of 17.5% and the other 15%.

The most important technical parameter of the solar battery, which has a major impact on the efficiency of the entire installation is its useful power. It is determined by the voltage and output current. These parameters depend on the intensity of the sunlight falling on the battery.

Electromotive force of the individual solar cells does not depend on their size and decreases with heating of the battery by the sun, about 0.4% to 1 gr. C. Output current depends on the intensity of solar radiation and the size of the solar cell. The brighter the sunlight, the more current is generated by solar cells. The charging current and output power in cloudy weather sharply reduced. This is due to the decrease output by the battery current.

If sunlit, the battery is shorted to any load with a resistance RL, the circuit appears the electric current I, the magnitude of which is determined by the quality of the photoelectric Converter, light intensity and load resistance. Power PH, which is released in the load is determined by the product PH = IнUн, where u n the voltage at the terminals of the battery.

Most power released in the load at a certain optimal resistance Rопт, which corresponds to the highest coefficient of performance (COP) conversion of light energy into electrical energy. For each Converter has its own value Rопт, which depends on the quality and size of the working surface and the degree of illumination.

Solar battery consists of separate solar cells which are connected in series and in parallel in order to increase the output parameters (current, voltage and power). A series connection of the elements increases the output voltage when the parallel – output current.

In order to increase the current and voltage combine these two connection method. In addition, with this method of connection the failure of one of the solar cells does not result in failure of the entire chain, i.e. increases the reliability of the entire battery.

Thus, the solar battery consists of parallel-series connected solar cells. The magnitude of the maximum possible current given by a battery is directly proportional to the number of parallel-connected, electromotive force, series-connected solar cells. So, combining connection types, assemble the battery with the required parameters.

Solar cells battery continuada diodes. Usually they are 4, one on each quarter of the battery. Diodes protect from failure of the battery, which for some reason was dimmed, i.e. if at some time the light on them misses.

Battery temporarily generates 25% less output power than in the normal light of the sun the entire surface of the battery.

In the absence of these diodes solar cells will overheat and fail, as they are time blackout transformed into consumers of current (the battery via solar cells), and if you use diodes they Sotiroudas and the current through them is not.

Resulting electric energy is stored in batteries and then given to the load. Battery chemical current sources. The battery is recharged when attached to it a potential which is greater than the voltage of the battery.

The number of series and parallel connected solar cells must be such that the operating voltage supplied to the batteries taking into account the voltage drop in the charging circuit is slightly greater than the voltage of the battery, and the load current of the battery provided the required value of the charging current.

For example, for charging a lead battery of 12 V, you must have a solar panel consisting of 36 items.

In low sunlight the battery decreases and the battery gives electrical energy to the power consumers, i.e. the battery constantly working in the mode of discharge and recharging.

This process is controlled by special controller. Under cyclic charge requires constant voltage or constant current charge.

In a good light battery fast charges to 90% of its nominal capacity, and then with a lower charge rate to full capacity. Switching to a lower charge rate is made by the controller of the charger.

The most effective use of special batteries gel (in the battery as the electrolyte is applied sulfuric acid) and svincovye batteries are made in AGM technology. These batteries do not need special conditions to install and does not require maintenance. Passport service life of such batteries is 10 — 12 years if the depth of discharge of 20%. The battery should never be discharged below this value, otherwise their lifespan is reduced dramatically!

The battery connected to the solar battery through the controller, which controls her charge. When the battery is at full capacity by the solar battery is connected the resistor which absorbs the excess power.

In order to convert DC voltage from batteries into AC voltage that can be used to supply the majority of power consumers, together with solar panels you can use a special device – inverter.

Without using the inverter from the solar panels can feed the power consumers operating at a constant voltage, including various portable devices, energy saving lights, for example, the same led bulb.published


P. S. And remember, only by changing their consumption — together we change the world! ©

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