RedditorsArGrb t1_iu6wtv8 wrote
Reply to comment by aecarol1 in Low-cost 'transparent' solar cells reach new efficiency record, electricity-generating windows incoming? by VeterinarianProper42
>You can combine multiple windows to a shared inverter, but if one window is shaded (even a bit), then all the windows must turn off.
what is your basis for this (ridiculous) statement?
aecarol1 t1_iu6xm1e wrote
Because that's how solar panels work. There are technologies to mitigate this, but they require more complex wiring and more sophisticated electronics.
If all the panels share one inverter (least expensive option), and if one panel has shade (even partial shade) then the entire array shuts down. If it doesn't the shaded sections actually consume power and will become very hot. Bypass diodes will help, but not always.
If you have micro inverters (each panel gets its own inverter) then one shaded window only reduces the power by that specific window, all is good. But now you need an expensive inverter box for each window. This is not cheap,
There are lots of schemes and systems to work around this and they work to varying degrees, but the thing in common is that they require more electronics to make that work and the entire point of this is to be "cheap".
https://www.solaredge.com/sites/default/files//se_technical_bypass_diode_effect_in_shading.pdf
If that's not enough, I can provide endless cites for the solar panel shading problem and the current solutions.
RedditorsArGrb t1_iu6yv95 wrote
yeah, I know what bypass diodes are. since you know what they are too it's kind of strange that you wrote a comment pretending they don't exist.
aecarol1 t1_iu6zf7v wrote
My point is that this can be fixed, but requires a lot more than the dead-simple shared inverter. That goes against the central point that this is supposed to be "cheap" and easy to deploy.
Low windows are often shaded by parked vehicles, trees, and shrubs. Tall buildings are often in dense places with other tall buildings that cast shadows.
This can work, but not for most places.
Either way, they have only shown this lasts 500 hours and they've only tested something slightly bigger than one-square inch. This is no better than the endless updates we get on "breakthrough batteries" every week that almost never end up working as well as hoped and almost never ship.
When they actually get this to last years, and they get it to work on full sized windows, and they get it uniform to not look splotchy and they keep their efficiency, and they solve the shading problem. Then we'll have something exciting. Right now it's a press release and nothing more.
RedditorsArGrb t1_iu72aup wrote
are bypass diodes "a lot more"? or are they a cheap and common element of most existing PV systems?
and yes, those major technical challenges mean this is very far from the market, if it ever makes it there, and all the articles deliberately do a poor job of explaining that.
but you can do better than being one of the many "helpfully" chiming in to let us know windows need to let some sunlight through as if that dooms the economic prospects out of the gate. It doesn't - these technologies are cheap to fabricate and new buildings are going to need glass somethings in the window frame. "It will always be better to build a normal building but then also pay a crew to go mount and install conventional solar panels in a field" is very much not a certainty, and private building developers probably don't care very much even if it's true.
aecarol1 t1_iu77mzp wrote
I'm "one of those guys" because the crowd that loves this idea heavily overlaps the "put solar panels on the roads" people. There is so much wrong with that idea it boggles the mind people don't think about it and rush to support a really crappy idea.
People like simple solutions to complex problems, especially those that show we "are doing something" especially with "out of the box thinking" technology.
This idea is certainly better than solar roads, but even with their "breakthrough" this isn't really ready for prime time. Even if this was "built into the windows" it still has to be wired into the building and all the support electronics such as inverters, controllers, etc, has to be wired and installed.
It's a lot easier to have a crew on a single flat roof, free to run conduit without cosmetic concerns, than it is to have electricians run extra wiring through walls and install extra electronics in every windowed room on every floor.
If all the ducks line up just right, this idea might well have a net positive, but it's far from clear and the history of this kind of announcement indicates it's not likely to.
We need to look at this holistically. After the easy fix of solar on the roof, is the money better spent on solar windows or on more efficient lighting or air conditioning?
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