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This article is dedicated to explain how to match the solar panels with the batteries. The proper functioning of the photovoltaic installation depends on the wise selection of solar panels. Therefore, such activity is left to qualified specialists. However, it is worth knowing some of the most important parameters of solar panel selection, so that you can sometimes do it on your own. Panels should not be too small or too large, as this leads to inadequate battery charging force generation.

How to choose a photovoltaic panel for the battery?

Not knowing   how to choose a solar panel for a battery  , it is worth relying on the knowledge and skills of professionals. People with extensive experience in the photovoltaic industry will have no problem with it. The selection of photovoltaic panels  can be made to depend, among others  , on their correct size. Large panels lead to significantly higher costs and at the same time charge batteries too quickly. On the other hand, panels that are too small mean that the power flow is limited. Incorrect selection may cause damage to the controller used.

How to choose the power from solar panel to battery?

Selecting a battery for solar panels  can be done in several different ways. One of the most important parameters in this case is the power of the solar panel. Traditional solutions will be 100W panels. However, this value can change due to:

  • temperature changes,
  • the degree of sunlight.

As a result, the actual value can decrease by up to 10%, so the total must be multiplied by 0.9. Going to the heart of the matter, charging a 100 Ah battery with 100 W solar panels is about 13.5 hours. Of course, it depends on the prevailing weather conditions, so it would be good to know it and know how  the selection of photovoltaic panels for the battery is carried out  .

How to connect a solar panel to a battery?

Another issue when choosing solar panels for batteries is their correct connection. Sometimes this can be an activity that average users will not be able to “skip” and will need specialist support. The key is to follow all the manufacturers’ recommendations.

If those interested do not know   how to connect a solar panel to a battery  , they should be fully aware that the used solar battery must be connected to the charge controller from the very beginning. Then such a regulator must be connected to the previously purchased battery. As you can see, it is not a very complicated process, so most people can handle it without any problem. However, some technical skills are needed. 

There must be a properly selected fuse between the regulator and the battery. If users neglect it, it can have very unpleasant consequences. A short circuit of the cables can cause, among others,  to trip.

Selection of solar panels for batteries: what about the charging time?

Anyone who chooses solar panels for batteries must know   how to calculate solar time  . It is important to analyze the charging time of the battery. Manufacturers recommend using batteries that can be recharged within 10 hours of connection to charging.

Having no idea   which photovoltaic panel for a 100Ah battery  will work best, remember that a 100Ah battery must be charged with a current of 10A. Thanks to this, the charging time will not exceed the aforementioned 10 hours. The same principle is used by people who do not know   which photovoltaic panel for a 200 Ah battery to  choose in the stores of their choice. For 200 Ah batteries, controllers with a current rating of 20A should be selected. 
The minimum battery charging time should not be less than 5 hours. This will prevent unpleasant events. The key element, however, is to pay attention to changes related to the decrease in the nominal capacity of the battery (the life of the battery and its charging time decrease over time).

Solar panels and batteries – a brief overview

The entire article deserves a short summary. As you can see, solar panels for batteries are selected based on several important parameters. Those interested should take into account, among others:

  • solar  time (battery charging time),
  • regulator power (according to the manufacturer’s instructions),
  • correct connection of the solar battery to the battery,
  • correct selection of fuses.

Fortunately,   calculating solar time  shouldn’t be the hardest part. You can always request the support of qualified professionals.

Selected panels cannot be too small or too large (to generate the correct voltage). In addition, users can choose between two basic types of regulators: PWM (for small photovoltaic installations, for panels with a maximum power of 175W – they are characterized by a fairly low price) and MPPT (possibility of working in the shade, increasing efficiency ). up to 30%). The right panels and regulators will make the photovoltaic installation more durable and dynamic, and at the same time resistant to breakdowns.

PWM solar regulators MPPT solar regulators