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Dylan16807last Tuesday at 6:51 PM1 replyview on HN

They don't build them in deserts that far north, do they?

I got this "fixation" by doing the math to figure out why panels do so badly when there's still seven and a half hours of daylight.

The insolation per square meter of ground is very low when the sun is near the horizon. But the insolation of a flat surface at 60 degrees of tilt is still pretty good. If you avoid shade.

Please tell me you have no disagreements with that. It's basic math.

So as you said with basic panels "one cell being shaded criples the output of the entire row". Normal commercial installs don't try to capture the morning sun. But in the middle of winter in Denmark the "morning" sun is basically all you have access to.

You said "They don't care about shade when the sun is low because when the sun is low the incidence angle is terrible in the first place."

If you tilt really far and avoid shade, you counteract the bad incidence angle. A single square meter of panel can absorb the light that would have hit 6 square meters of ground.


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littlestymaarlast Tuesday at 7:44 PM

> They don't build them in deserts that far north, do they?

I'm not aware of any desert in Denmark…

But you say the design is driven by lack of space, then why do they use the same design in deserts?! That's my question. Denmark doesn't have much free space, but Sweden do, land is cheap in many places there, yet the Swede don't design their plant differently.

> Normal commercial installs don't try to capture the morning sun. But in the middle of winter in Denmark the "morning" sun is basically all you have access to.

And yet you insist commercial plants don't do that? Why? Are they stupid?

> If you tilt really far and avoid shade, you counteract the bad incidence angle.

Only the vertical angle, not the horizontal one… And again it makes no sense to optimize for winter morning sun when there's only 2 hours of sunlight per day in average during winter…

You could set up a football field of our perfectly optimized morning sun solar panels, plus the same for evening sun, and you'd still have failed to power a house for the full month between January and February where the sun often don't show up once, and in that time span you've already exceeded the 10% non-solar budget in that mental exercise…

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