Cold Weather’s Impact on Solar PV Systems

It’s a common misconception that a solar PV system relies on the heat from the sun to generate electricity. In fact, the cooler the climate, the better. Let’s look at how varying ambient temperatures affect your solar system. 

Contrary to what you might think, the reason that many so-called solar farms are positioned in desert areas around the world is not because of the average daytime ambient temperatures that these regions experience, but rather the amount of uninterrupted sunlight that they are exposed to on any given 24-hour period. Indeed, a modern solar PV panel, including the items attached to your home’s roof, rely less on the outside temperature and more on unfiltered (undiffused cloud cover) access to the sun’s abundant light. 

As a reminder, a solar photovoltaic (PV) panel houses rows of electrons that lay “at rest” when not exposed to the sun’s rays, however, under normal condition exposure, these rays activate the electrons. The resultant frantic activity generates the electricity that is then fed into your home’s solar inverter, for household consumption. T the more dramatic this reaction to sunlight (not heat), the more energy is created. This means that a solar PV panel is more efficient on cooler winter days than in the middle of summer, with the difference between the “at rest” and “active” phases being more significant in the first scenario. 

Studies have shown that the only disadvantage that homes in the Northern Hemisphere have when it comes to the generation of electricity via a solar PV system is the significantly shortened periods of daylight hours experienced through winter months when compared with other parts of the world. Here, the installation of appropriate solar battery storage solutions help to keep the lights on past sunset. 

Though their efficiency is reduced on cloudy or even rainy winter days, a solar PV system is still able to generate energy from any prevailing sunlight. 

Too much heat, on the other hand, can also stifle the efficiency of a solar PV system. According to the Standard Test Condition (STC), the industry-wide standard by which the performance of a PV panel is measured, every solar panel has its own heat tolerance value, known as a maximum power point (Pmax). This coefficient reflects how much your panel’s efficiency will drop with each increase of 1 degree Celsius, above 25 degrees Celsius. 

The optimal conditions under which your solar PV system will generate the most energy is a crisp, bright, and cloudless day.