As we mentioned in a previous article, temperature can have a large impact on the power production of your solar panels. The colder a solar panel is, the more efficient it produces power. The warmer a solar panel is, the less efficient it produces power.
But, how do you calculate how much more or less power you are producing because of the temperature? This is where the temperature coefficient come into the picture.
To calculate temperature coefficient, there are several details you need to know. First of all, you need to know the Temperature Coefficient of the Maximum Output Power (Pmax ). This information can be found in the solar panel specs, which can typically be located on the manufacturer’s website. The graphic above has the temperature coefficient information circled in blue. As you can see, the temperature coefficient of the Mission Solar Mono 72 cell 340W solar panels is -0.419%/°C.
Next, you will need to know the temperature of the solar panels. It is important to remember that the temperature of the solar panels might not be the same as the temperature of the air. For our examples, we will use a low temperature of -10°F(-23°C) and a high temperature of 100°F(38°C).
At this point, it is important to know that solar panels are tested at a steady temperature of 77°F(25°C). Therefore, we must subtract this amount from each of the temperatures.
(-23°C) – (25°C) = -48°C
(38°C) – (25°C) = 13°C
From here, we will take the adjusted temperatures and multiply it by the temperature coefficient
(-48°C) * (-0.419%) = 20.11%
(38°C) * (-0.419%) = -37.58%
As you can see, at these temperatures, the cold day will be a 20% increase in power production efficiency, while the hot day will see a 38% decrease in power production efficiency.
Given that the Mission Solar panels produces 340W of power, we can now calculate the total power gain or loss due to temperature, as well as the maximum power output.
(340W) * (20.11%) = 68.37W power loss : (340W) + (68.37W) = 408.37W max power output
(340W) * (-37.58%) = -127.77W power loss : (340W) – (127.77W) = 212.23W max power output
As you can see, temperature can have a huge impact on the power production of solar panels. Therefore, it is important to factor this into calculations when estimating the power production of a solar installation, as well as deciding how well solar power will work for you.
If you have any questions about solar power, contact Tick Tock Energy here.
