Is there a source that I can use that will tell me what the expected cloud cover will be?
The national weather service in the USA is terrible for this even for basics. Today for instance was going to be cloudy when it actually turned out to be sunniest day we had in a long time and was able to fully charge my battery. Even when it is "cloudy" there are obviously different levels of cloudiness that may allow a significant percent of charge. Surely the big PV farms have this type of info, where are they getting it from?
The national weather service in the USA is terrible for this even for basics. Today for instance was going to be cloudy when it actually turned out to be sunniest day we had in a long time and was able to fully charge my battery. Even when it is "cloudy" there are obviously different levels of cloudiness that may allow a significant percent of charge. Surely the big PV farms have this type of info, where are they getting it from?