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> 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.

> 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.

Dylan16807 6mo ago
> Not at all… > The sun isn't just going up and down you know it also circles from east to West… Over a narrow range in winter. You get good coverage from pointing very south and avoiding shade. > I'm sorry but this is utter bullshit. The commercial plants do avoid shade as much as possible because shade destroy efficiency They do not avoid it "as much as possible". The panels are shading each other in that very photo, and that photo wasn't taken at the crack of dawn. It's basic trigonometry. Narrow spacing needs the sun to get pretty high before shading stops. A roof install never shades itself. The difference matters. > 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. Wrong answer. Those panels are plenty tilted for low incidence sunlight. The ones in front will make plenty of power in the winter. But the ones behind them won't. The limiter is the price of land. If land was free I guarantee they would spread them out more. And a home install doesn't have this specific issue. > Yes, but that's over-paneling… No it's not! If you need it for most of the year it's not "over"! > 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… If you need 5x or more for half the year, you calculated "x" wrong. Your math is what's nonsense here.
- littlestymaar 6mo ago
  > They do not avoid it "as much as possible". The panels are shading each other in that very photo You haven't linked the photo… > It's basic trigonometry. Narrow spacing needs the sun to get pretty high before shading stops. Of course it's “basic trigonometry”… It doesn't matter if the panels are shaded when the incidence angle is high anyway! > The limiter is the price of land. If land was free I guarantee they would spread them out more. They wouldn't, they'd just put more panels on a bigger surface. And again, industrial actors are maximizing the economic output they can make. Whatever decision you take at your level, it's going to be more expensive than what they are doing, and more efficient. > No it's not! If you need it for most of the year it's not "over" Yes it is… By definition you are over-paneling if your peak production is higher than what you use. This threshold is important because cost calculations only works when you haven't reached that yet! > If you need 5x or more for half the year, you calculated "x" wrong. Your math is what's nonsense here. X is the value for which the cost/MWh makes sense. The further you got from there, the bigger fraction of the power is unexploited and the higher the cost per unit of useful electricity rises. I didn't invent these concepts or these calculations, those are standards when talking about solar.
  - Dylan16807 6mo ago
    > You haven't linked the photo… The one at the top of the article. > They wouldn't, they'd just put more panels on a bigger surface. Given a specific budget they can only buy so many panels. Free land would change the tradeoffs. > And again, industrial actors are maximizing the economic output they can make. Based on current costs. Change the costs and the methods change too. > Whatever decision you take at your level, it's going to be more expensive than what they are doing, and more efficient. No. I already have the land and the house. That means most efficient for me is different. I don't want to waste any more of our time arguing about how to define X so I'll skip the rest.
    - littlestymaar 6mo ago
      This makes no sense: solar plants in the deserts have the same shape yet even though the land is pretty much worseless. Where did you get your morning shade fixation from?

Dylan16807 6mo ago

> Not at all… > The sun isn't just going up and down you know it also circles from east to West… Over a narrow range in winter. You get good coverage from pointing very south and avoiding shade. > I'm sorry but this is utter bullshit. The commercial plants do avoid shade as much as possible because shade destroy efficiency They do not avoid it "as much as possible". The panels are shading each other in that very photo, and that photo wasn't taken at the crack of dawn. It's basic trigonometry. Narrow spacing needs the sun to get pretty high before shading stops. A roof install never shades itself. The difference matters. > 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. Wrong answer. Those panels are plenty tilted for low incidence sunlight. The ones in front will make plenty of power in the winter. But the ones behind them won't. The limiter is the price of land. If land was free I guarantee they would spread them out more. And a home install doesn't have this specific issue. > Yes, but that's over-paneling… No it's not! If you need it for most of the year it's not "over"! > 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… If you need 5x or more for half the year, you calculated "x" wrong. Your math is what's nonsense here.

littlestymaar 6mo ago
> They do not avoid it "as much as possible". The panels are shading each other in that very photo You haven't linked the photo… > It's basic trigonometry. Narrow spacing needs the sun to get pretty high before shading stops. Of course it's “basic trigonometry”… It doesn't matter if the panels are shaded when the incidence angle is high anyway! > The limiter is the price of land. If land was free I guarantee they would spread them out more. They wouldn't, they'd just put more panels on a bigger surface. And again, industrial actors are maximizing the economic output they can make. Whatever decision you take at your level, it's going to be more expensive than what they are doing, and more efficient. > No it's not! If you need it for most of the year it's not "over" Yes it is… By definition you are over-paneling if your peak production is higher than what you use. This threshold is important because cost calculations only works when you haven't reached that yet! > If you need 5x or more for half the year, you calculated "x" wrong. Your math is what's nonsense here. X is the value for which the cost/MWh makes sense. The further you got from there, the bigger fraction of the power is unexploited and the higher the cost per unit of useful electricity rises. I didn't invent these concepts or these calculations, those are standards when talking about solar.
- Dylan16807 6mo ago
  > You haven't linked the photo… The one at the top of the article. > They wouldn't, they'd just put more panels on a bigger surface. Given a specific budget they can only buy so many panels. Free land would change the tradeoffs. > And again, industrial actors are maximizing the economic output they can make. Based on current costs. Change the costs and the methods change too. > Whatever decision you take at your level, it's going to be more expensive than what they are doing, and more efficient. No. I already have the land and the house. That means most efficient for me is different. I don't want to waste any more of our time arguing about how to define X so I'll skip the rest.
  - littlestymaar 6mo ago
    This makes no sense: solar plants in the deserts have the same shape yet even though the land is pretty much worseless. Where did you get your morning shade fixation from?