More MPPT Confusion and Question
Still trying to understand my MPPT set-up and what would be the effect of changing things a bit. My 230w (30.0 Vmp x 7.7 Imp) poly panel has a Vmp of 30.0v with a measurement tolerance of +/- 3% S...
Forum Discussion
Hi,
For those of us who do not acronym well NOTC = Normal Operating Cell Temperature ratings. NOCT recognizes a bit of reality and assumes the following: 800 watts per square meter of Sunlight Irradiance, an average of 20'C (68'F) Air Temperature, an average wind velocity of 1 meter per second (2.24 miles per hour), with the back side of the solar panel open to that breeze (as opposed to being on a roof where heats builds up under the panels).
Given those conditions, what is the Temperature of the Solar CELL (not the air)? The average was found to be about 48'C (118.4'F). Some panels are a little higher and some a little lower. What you need to know is that ALL solar panels experience a voltage drop as they heat up. Since Volts x Amps = Watts, the power of the solar panel diminishes as they heat up.
For those of us who do not acronym well NOTC = Normal Operating Cell Temperature ratings. NOCT recognizes a bit of reality and assumes the following: 800 watts per square meter of Sunlight Irradiance, an average of 20'C (68'F) Air Temperature, an average wind velocity of 1 meter per second (2.24 miles per hour), with the back side of the solar panel open to that breeze (as opposed to being on a roof where heats builds up under the panels).
Given those conditions, what is the Temperature of the Solar CELL (not the air)? The average was found to be about 48'C (118.4'F). Some panels are a little higher and some a little lower. What you need to know is that ALL solar panels experience a voltage drop as they heat up. Since Volts x Amps = Watts, the power of the solar panel diminishes as they heat up.
