Solar Power IN The rain
One common misconception people have with solar panels is that here in Florida, during our rainy days the panels will not provide much electricity. I always tell my customers that if you can see outside, the panels are producing plenty of electricity. As a rule of thumb, if there is enough sun light to get a sunburn there is enough to produce energy. On a bright sunny day, they will always produce more power, but even on a rainy day you will have energy production. When the sun comes out, it releases photons to the earth, and those photons are captured inside those photovoltaic cells, the cells get super excited and bounce around, which is what creates electricity. It’s all about the relationship of the sun to the earth. The sun gives us enough light in one day to provide the entire world its energy needs for an entire year!!
So How Much Energy is lost in the rain?
That entirely depends on the cloud cover and the amount of light that makes it onto the panels. Cloud cover is the real enemy of solar panels as it stop the photovoltaic cells from capturing protons and generating energy. On the contrary, rain water can actually help the panels as it cleans the surfaces and allows more light to hit the cells. When sizing systems for my customers I always reference pvwatts.gov to check annual solar radiation figures and accurately determine the correct system size to fit my customers needs. PV Watts uses typical year weather data that represents multiple years over the Orlando Area and will properly account for these rainy and cloudy days so there is no guess work in my system sizing recommendations. Additionally I can adjust parameters like roof tilt, panel efficiency and panel azimuth to ensure I am offering the correct system every-time.
So in conclusion, while rain is a factor when measuring a solar system output, a properly sized system will use historic data to ensure the energy output is adequate for the customers annual needs. Never worry about a raining day here and there, its all part of the plan and a great way to get a free solar panel cleaning. 😀