alt Hacker News> 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…
> I'm not aware of any desert in Denmark…
Right! A lack of places with such super free land that also have horrible sun angles.
> But you say the design is driven by lack of space, then why do they use the same design in deserts?!
The desert builds don't have to deal with the same horrible sun angles.
But whatever, I might be wrong on what they would do with free land. That was a guess, I admit it. That guess was to illustrate my point about angles. It's not a critical part of my argument.
It's a fact that solar panels on a roof avoid the shading problem, while a normal commercial layout does not. Pure mathematics.
> Only the vertical angle, not the horizontal one…
The horizontal angle doesn't change very much. If you point flat 50-60 degrees south (the year-round optimal angle for Denmark) you will get a significant amount of sun no matter the season if you avoid shade. Winter sun is less than average but it's close to 50%, not 5%.
> 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…
That's so close to understanding my argument!
Commercial plants don't bother. They're not optimal for winter. But if you build on a slanted roof you get that optimization for free. So a home install actually becomes better than a commercial install for this specific use case.
But it's not 2 hours of significant light, it's more than that. Clouds don't make the sun useless.
> where the sun often don't show up once
Nah.