alt Hacker News> These are equivalent unless you over-panel.
I don't think so? If your Nevada desert load factor is 25%, then we're talking about it dropping to 12% or something. Unless I'm not understanding the way you're using those numbers.
> unless you over-panel
Some amount of over-paneling would be perfectly fine here. Not 10x, agreed.
> Those are commercial solar farms, optimally angled under the constraint that the cost must be reasonable.
They're optimized mostly for total power output, which affects things. And they don't have a free house to be mounted on.
They're also not trying very hard to avoid shade. The commercial plant has to buy land for every panel, while a house has much more land than panels. That's a massive difference. When the sun is near the horizon, you want your rows of panels to be very far apart or at different heights. Which means:
A commercial solar plant like one pictured in the article will have each panel shade most of the next row's panel when the sun is very low. To stop this effect, you need to put the rows super far apart, or put them at different heights (like on a roof). This means a home install could have 4x as much light hit each panel in the depths of winter.
> Do you have an idea of how much it would cost?!
It's a thought experiment. Don't worry about the cost of tracking. Because it turns out, a 60 degree angle that completely avoids shade is just as good. The key is avoiding shade. Commercial plants do not avoid shade. Rooftop installs do avoid shade (they won't be quite as tilted, but they'll still have a huge advantage). If you have a nice big yard you can also avoid shade.
> The 10% load factor happening right now is because it's cloudy (light clouds, no rain, but still). It peaked at 40% in recent days with proper sun, but it happened only a handful of times in the entire winter.
I think you didn't go through the full implications of this.
It's mid-april. If it's cloudy this far from the depths of winter, that means needing more panels is much more of a year-round thing. Which means a household array needs to be bigger as a baseline. Which means it can tolerate more losses in the winter.
The thing that would make 90% unreasonable is the difference between winter and non-winter power output. If spring and/or fall also require lots of panels, then 90% gets more realistic because expanding the system saves money for more months of the year.
> And they don't have a free house to be mounted on.
Rooftop solar is more expensive than solar farms. There's nothing free in putting a solar panel on a roof. (Which is a pity because it means that if your country doesn't have a desert, the economically optimal way of installing solar panels is deforestation, but that's the world we live in…).
> Because it turns out, a 60 degree angle that completely avoids shade is just as good
Not at all…
The sun isn't just going up and down you know, it also circles from east to West…
> They're also not trying very hard to avoid shade. […] When the sun is near the horizon, you want your rows of panels to be very far apart or at different heights.
> A commercial solar plant like one pictured in the article will have each panel shade most of the next row's panel when the sun is very low.
I'm sorry but this is utter bullshit. The commercial plants do avoid shade as much as possible because shade destroy efficiency (one cell being shaded criples the output of the entire row…).
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. You want your average panel directed south (or north in the southern hemisphere), when the sun is low, it's going to be completely in the East or completely in the West, and you care about the cosine of your incidence angle, which means the output is going to be near zero even without any shade whatsoever.
> It's mid-april. If it's cloudy this far from the depths of winter, that means needing more panels is much more of a year-round thing.
Of course clouds are a year-round thing, what do you think… But sunny days are still much more frequent in summer.
> Which means a household array needs to be bigger as a baseline
Yes, but that's over-paneling…
> The thing that would make 90% unreasonable is the difference between winter and non-winter power output. If spring and/or fall also require lots of panels, then 90% gets more realistic because expanding the system saves money for more months of the year.
Sigh… Over-paneling 10x isn't going to be more worth it just because in spring and winter you need 5x. That's a nonsensical argument…
I'm sorry but you obviously have no idea about any of these things, I can only invite you to document yourself better at this point, because you're just pilling up crazy takes on top of crazy takes here.