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Comment by wkat4242 | Hacker News Reader

Weird, a parabolic dish makes no sense if you point it directly at the sun. Most panels will be pointed at suboptimal angles. A flat plate mounted on the existing az/el tracking of the original dish would be optimal. Stuff that plate full of panels and track the whole contraption to the sun and all panels will be perfectly aligned.

If you replace the panels with mirrors and have an ultra efficient high power panel in the middle the dish form factor would work (and this is how they built them in the 80s though I think they were heating water for steam back then) but that's not what they're doing here.

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> Most panels will be pointed at suboptimal angles.

I do wonder how electricity pricing plays into this: having panels that are optimized for production in mornings and afternoons will produce less overall, but could provide more valuable power overall.

you could just add a triangular shim under each panel that make them flat towards a common level. Each ring would need their own shim height but since you need some mounting hardware anyway this would add only a bit of weight.

Good point! That would work yeah. The placement will have to be modified a bit to avoid shadows but that would work just as well.

With a dish that can be oriented to always face the sun, there should never be any shadows

Mounting hardware like that can easily cost nearly as much as the panels with how cheap panels can be right now, and the cost of the extra labor to install standoffs.

That mounting hardware shouldn't cost any more than standard mounting hardware - it'd be a simple matter of making one pair of standoffs taller than the other. You are going to need standoffs, and the labor to install them anyway.

Yes, but suddenly you need different kinds of standoffs instead of one uniform size. This makes manufacturing a bit more expensive, logistics a bit more challenging, and installation a bit more complicated.

All of this means it's going to be more expensive than standard mounting hardware. Not by a lot, but solar panels have become cheap enough that even small differences matter.

Yes, but on my napkin, all of this will create significantly more power which more than offsets those costs.

The entire thing is on a coaxial mount. If you need less power, just turn it away from the sun, intentionally designing suboptimal features to chase uneven demand loads (between winter and summer) would not be a worthwhile strategy.

You save maybe a few thousand dollars in solar panels by installing the flat plate, but you have to validate the additional structure.

There's something heartwarming about this: Just slapping a bunch of panels on any old abandoned structures and calling it a day seems so fundamentally un-Swiss -- It's like they're starting to become human!

(In humor of course -- Switzerland is impressive, I'm fully aware that there's plenty of rural agriculture and other such "suboptimal imperfection" there etc.)

I assumed this was going to be about repurposing the dish as a solar concentrator, but they're literally just lining the dish with standard solar cells. This makes no sense beyond the PR value -- you could literally just put these panels on a southward-facing slope and get better net efficiency...

Plus they should have removed the collector, as the arms will cause some of the panels to block energy flow in the system.

I’m also not convinced this is the densest layout for the panels. Pretty sure I could get 5-10% more onto this dish, not counting removing the focus.

The antennas/mount are rated for a certain amount of weight and might not support fully packed panels.

With microinverters it doesn't really matter if some panels aren't optimally places.

A flat plate won't have the rigidity of the existing dish, and replacing it probably will cost more than the project is worth.

Yeah the real story here seems to be that solar panels now so cheap that people can waste them on pointless stunts like this.

Put more generously: solar panels are so cheap that other factors (existing scaffold, ease of installation, aesthetics, …) dominate installation decisions.

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