This shows you the differences between two versions of the page.
Both sides previous revision Previous revision Next revision | Previous revision | ||
opinion:frater_secessus:solar_harvest [2023/02/17 15:07] frater_secessus [ununsual scenarios] |
opinion:frater_secessus:solar_harvest [2023/02/17 15:20] (current) frater_secessus [correlation with available direct light] |
||
---|---|---|---|
Line 36: | Line 36: | ||
* exceptionally low yield - less than 5% of rated | * exceptionally low yield - less than 5% of rated | ||
* thunderstorms, | * thunderstorms, | ||
+ | |||
+ | ===== correlation with available direct light ===== | ||
+ | |||
+ | This is harder to grasp and compute, but increases accuracy by factoring in location, time, etc.((It cannot account for // | ||
+ | |||
+ | - find solar zenith angle with app or calculator | ||
+ | - derive cosine of the above; this is the percentage of direct sunlight landing on a flat surface | ||
+ | - multiply this value by panel wattage | ||
+ | - the result is the theoretical direct light available at that time/place under clear skies.((since MPPT-based system losses typically are -15% and indirect lighting is +15%, an MPPT-based system might make this direct-light power level under clear skies.)) | ||
+ | |||
+ | I have observed the following cosine-based direct light percentages: | ||
+ | |||
+ | * clear skies: | ||
+ | * bright overcast skies (shadows thrown): | ||
+ | * overcast: 58% of theoretical direct sun | ||
+ | |||
+ | |||
+ | |||
+ | |||
+ | |||
+ | |||
+ | |||