The DC voltage of the electricity generated by the photovoltaic panel is 48v

Open circuit 20.88V voltage is the voltage that comes directly from the 36-cell solar panel. When we are asking how many volts do solar panels produce, we usually have this voltage in mind. For maximum power voltage (Vmp), you can read a good explanation of what it is on the PV Education website.

The solar panel voltage output comes from the photovoltaic effect. This is when sunlight hits certain materials, like silicon, in the solar cells. These solar cells are part of a solar panel. These materials can make an electric current with light, called the photovoltaic effect. Sunlight, or photons, shines on the solar cells.

As we can see, solar panels produce a significantly higher voltage (VOC) than the nominal voltage. The actually solar panel output voltage also changes with the sunlight the solar panels are exposed to.

How do different solar panel technologies affect voltage? What is the typical lifespan and degradation rate of solar panels? A single solar cell can produce an open-circuit voltage of 0.5 to 0.6 volts, while a typical solar panel can generate up to 600 volts of DC electricity.

Voltage output directly from solar panels can be significantly higher than the voltage from the controller to the battery. Maximum Power Voltage (Vmp). The is the voltage when the solar panel produces its maximum power output; we have the maximum power voltage and current here. Here is the setup of a solar panel:

Three primary terms commonly used to describe solar panel voltage characteristics are Voc (open-circuit voltage), Vmp (voltage at maximum power), and Imp (current at maximum power). Voc represents the maximum voltage output of a solar panel when no load is connected, i.e., under open-circuit conditions.