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am i stupid or are solar panel's efficiency independent on latitude
(discuss.tchncs.de)
Consider the following drawing:
I take it that solar panel's generated electricity would be the same whether it's installed in scandinavia or africa, as long as it faces in the same direction? or am i stupid
i'm asking this because everywhere i hear how "solar panels have higher efficiency near the equator", but that's just not true. Maps such as these are common on the internet:
And they suggest that solar energy around the equator would be twice as available as on northern latitudes, but actually that's just the solar irradiation if the panels weren't inclined, but in practice, they were likely will be. So they receive similar amounts of power.
edit: so, it's the cloud cover. got it; thanks :D
isn't the atmosphere transparent for most of the light, though? (except UV, but that gets filtered out even at the equator, so it's the same everywhere again)
The atmosphere is mostly transparent; see the table near the bottom of this Wikipedia page for some numbers. At an angle of 45 degrees from vertical you're getting 91% of the energy, and at 60 degrees you're getting 81%. A bigger problem is seasonal variation: during the winter at high latitudes you get very little energy. My city, at around 47 degrees latitude, sees the Sun peak at less than 30 degrees with under 10 hours of daylight for a quarter of the year. A solar array isn't as useful if it produces almost no power for much of the year, especially when people need a lot to keep warm.
It isn't perfectly transparent. It has dust, moisture, and other particles in the air that block or deflect a portion of the light.