It is obvious to think that solar panels perform well under sunny and hot climate as all this is related to sunlight.
But the answer is bit twisted.
Let's understand the basics first;
Our sun emits electromagnetic radiations that provide us light and heat for sustaining various life-forms on the earth's surface.
The visible light help solar panels to produce current
the solar cells do not like the heating effect that solar radiations produce.
The internal resistance of the solar cells increases when they get hot and they become sluggish and inefficient in producing current with every degree rise in the temperature.
In fact, the solar panels perform well and produce more current at lower temperatures.
Therefore, people living in hotter regions need to look at something special in solar panels that can fight the heating effect of sunlight.
Manufacturers are trying to minimize this effect by designing panels that have lower temperature coefficient of power.
"The temperature coefficient of power is a metrics that measures the reduction in power output with every degree rise in the cell temperature beyond 25°C
Remember: The cell temperature mentioned above is different from the ambient air temperature.
When air temperature is 25°C, the cells of the solar panel might be operating under 45°C to 50°C.
This science is similar to the case when you feel the car's window panes are hotter than the surrounding air.
In this post, I'll help you in picking the best solar panels for hot climate.
What are the best solar panels under hot climate?
The best solar panels are arranged on the basis of their power degradation rates.
The one whose power output degrades the least with every degree rise in the temperature is considered the best panel for hot climate.
Here is the list:
You can see that the Panasonic HIT+ model is on the top of the list with Temperature Coefficient of Power as -0.258 %/°C.
It means that whenever the cell temperature goes beyond 25°C, it will start losing 0.258 % of its Pmax with every degree rise.
Let me make it more clear with the help of an example:
Assuming you've 340 watts of Panasonic HIT+ model installed at your rooftop
its solar cell are operating at 45 °C.
In that case, the power loss can be calculated as follows:
45°C - 25°C = 20°C (The cells are operating at 20°C higher)
The power loss would be:
Temperature coefficient of power x temperature difference
= - 0.258%/°C x 20°C
= - 5.16% (The solar panel will lose 5.16% of its Pmax)
That is in absolute terms, it would be:
-5.16% x 340 watts = 17.54 watts
It means that Panasonic HIT+ 340 watts solar panel will lose 17.54 watts when it is operating at 45°C.
It is not that one panel is inferior to other but it all depends on the suitability and the climatic conditions.
In mild climate, each panel is equally good.
1) The Power Temperature Coefficient of - 0.4 %/°C is normal in most of the solar panels, it means that the panel will lose 4% with every 10°C rise in the temperature.
This loss can be as high as 25% - 30% at the higher temperatures.
If you're living in hotter climate then you should look for panels having less power degradation rate.
2) In hot regions, sunlight is good but due to heat, the temperature within the solar panel can reach as high as 90°C
it becomes difficult for the panel to operate unless it has a high operating range.
Therefore, you should look for the panels having high operating range.
3) The high temperature leads to Potential Induced Degradation (PID) losses in the solar panels, resulting in more leakage current that further deteriorates the power output.
Look for panels that are free of PID losses.
4) The panels should be installed in a way that there is always a gap in between the roof and the rear side of it. When wind passes through this gap, it cools down the solar panel.
5) Avoid installing solar panels near to dark colored objects as the dark color objects absorb more heat, resulting rise in temperature the surroundings.
When consider the above points while purchasing solar panels for hot climate,
I'm sure you're going to get smooth electricity for decades and that is profitable too.