5 ms·

Solar panels wear out pretty quickly, actually - within decades. UV light's nasty stuff.

FreeFull 8y ago
How quickly would a protective coating on the glass wear out? Or the green/brown colouring that gets added to beer bottle glass.
- Pharmakon 8y ago
  How much would such a coating reduce the efficiency of the panel though? I’m seriously asking btw, I don’t know the answer or very much about PV panels.
  - 14 8y ago
    That seems to be the fantastic part of this motor. Even if you traded off almost all efficiency in order for protectiveness of the material instead, this machine runs on such a low power you could make those trade offs. What you could use this motor for I am unsure.
    - Pharmakon 8y ago
      Too cool. Hey, could these bearings be used in something like a water wheel or windmill? I realize the technology isn’t there yet, but if it could then really you’d could have lowered maintenance costs, slightly increased efficiency, and probably a lot less noise.
      - MrEldritch 8y ago
        >technology isn't there yet In what sense? >lowered maintenance costs Not really, actually - hydrodynamic bearings already work on the "zero wear due to zero surface contact" principle. The reason this is using magnetic bearings is just because it needs super-super low friction, under super-tiny loads, in order to work. >Probably a lot less noise Bearings aren't generally noisy. If they were, they wouldn't be very good bearings!
        Pharmakon 8y ago
        I stand massively corrected on all fronts, thanks!
    - jaytaylor 8y ago
      The energy required is so small, I wonder if you could use a thermoelectric generator utilizing some tinfoil half in the sun and half in the shade. Maybe such a design could last longer than a solar panel based one.
  - jws 8y ago
    Only about 5% of the Sun's energy, as filtered by Earth's atmosphere, is ultraviolet. You can block it all with negligible efficiency loss at your solar panel. I'm not sure about UV filters that will be stable for 1000 years. Regular glass blocks most UV, but lets through about 25% of the frequencies close to blue. For museum and artwork protection time frames acrylic is popular. It blocks almost all UV and is still stable after 25 years. I don't know how that extrapolates to 1000 years.
- Retra 8y ago
  The glass isn't the thing that wears out, the PV cells are. And if you're keeping light from reaching those, then you're really defeating the purpose of the whole thing.
  - _Microft 8y ago
    It's using so little power that this should not be a problem. In the accompanying video it is stated that ...the most surprising thing probably is that it was being powered off a small solar cell under this dark blue plastic box. Any more power than that and the motor would spin up, lose control and fly out of stability. , https://youtu.be/wNcgnooayDc?t=129 https://youtu.be/wNcgnooayDc?t=129
- logfromblammo 8y ago
  Mineral coloration has literally a dozen different explanations. Most of them do not "wear out", but some of them change colors under irradiation. Green glass is green because of iron (II) oxide (FeO), which is usually a naturally occurring contaminant of the sand used for glassmaking. Amber glass is amber because of FeS2. Neither change color under normal weathering conditions. The duration of a protective coating depends on the coating, and its thickness. If you layer a glass pane under a synthetic sapphire pane, that would probably be better than a protective coating. The sapphire would protect the glass, and the glass would block UV-A.
frickinLasers 8y ago
At 8:15 in the video, he mentions a solar cell used while prototyping is under a "dark blue plastic box" to keep the thing from spinning out of control. There's probably not too much UV getting in there. You could probably hide the cell under the base and it would go until the printed parts crumble.
driverdan 8y ago
Their output decreases but they don't "wear out." This motor requires such little power a small solar panel would work for a very long time.
walrus01 8y ago
Modern high quality monocrystalline silicon PV cells, 156mm size, are commonly warranted for 80% or up to 84% of their original STC rating, after 25 years. PV cells definitely do degrade, but in terms of spinning a nearly frictionless thing in a vacuum, if a 5W rated single cell degrades to 2.5W over 75 years of being exposed to direct sunlight inside a glass vacuum jar, it's still way more than the required energy to keep the thing spinning. Here's an example of a 30 year warranty for a fully assembled module (60 or 72 cells encapsulated in glass and back film), at >80% after 30 years. http://www.jasolar.com/uploadfile/2018/0518/20180518093724135.pdf http://www.jasolar.com/uploadfile/2018/0518/2018051809372413...

How quickly would a protective coating on the glass wear out? Or the green/brown colouring that gets added to beer bottle glass.

Pharmakon 8y ago
How much would such a coating reduce the efficiency of the panel though? I’m seriously asking btw, I don’t know the answer or very much about PV panels.
- 14 8y ago
  That seems to be the fantastic part of this motor. Even if you traded off almost all efficiency in order for protectiveness of the material instead, this machine runs on such a low power you could make those trade offs. What you could use this motor for I am unsure.
  - Pharmakon 8y ago
    Too cool. Hey, could these bearings be used in something like a water wheel or windmill? I realize the technology isn’t there yet, but if it could then really you’d could have lowered maintenance costs, slightly increased efficiency, and probably a lot less noise.
    - MrEldritch 8y ago
      >technology isn't there yet In what sense? >lowered maintenance costs Not really, actually - hydrodynamic bearings already work on the "zero wear due to zero surface contact" principle. The reason this is using magnetic bearings is just because it needs super-super low friction, under super-tiny loads, in order to work. >Probably a lot less noise Bearings aren't generally noisy. If they were, they wouldn't be very good bearings!
      - Pharmakon 8y ago
        I stand massively corrected on all fronts, thanks!
  - jaytaylor 8y ago
    The energy required is so small, I wonder if you could use a thermoelectric generator utilizing some tinfoil half in the sun and half in the shade. Maybe such a design could last longer than a solar panel based one.
- jws 8y ago
  Only about 5% of the Sun's energy, as filtered by Earth's atmosphere, is ultraviolet. You can block it all with negligible efficiency loss at your solar panel. I'm not sure about UV filters that will be stable for 1000 years. Regular glass blocks most UV, but lets through about 25% of the frequencies close to blue. For museum and artwork protection time frames acrylic is popular. It blocks almost all UV and is still stable after 25 years. I don't know how that extrapolates to 1000 years.
Retra 8y ago
The glass isn't the thing that wears out, the PV cells are. And if you're keeping light from reaching those, then you're really defeating the purpose of the whole thing.
- _Microft 8y ago
  It's using so little power that this should not be a problem. In the accompanying video it is stated that ...the most surprising thing probably is that it was being powered off a small solar cell under this dark blue plastic box. Any more power than that and the motor would spin up, lose control and fly out of stability. , https://youtu.be/wNcgnooayDc?t=129 https://youtu.be/wNcgnooayDc?t=129
logfromblammo 8y ago
Mineral coloration has literally a dozen different explanations. Most of them do not "wear out", but some of them change colors under irradiation. Green glass is green because of iron (II) oxide (FeO), which is usually a naturally occurring contaminant of the sand used for glassmaking. Amber glass is amber because of FeS2. Neither change color under normal weathering conditions. The duration of a protective coating depends on the coating, and its thickness. If you layer a glass pane under a synthetic sapphire pane, that would probably be better than a protective coating. The sapphire would protect the glass, and the glass would block UV-A.

frickinLasers 8y ago

At 8:15 in the video, he mentions a solar cell used while prototyping is under a "dark blue plastic box" to keep the thing from spinning out of control. There's probably not too much UV getting in there. You could probably hide the cell under the base and it would go until the printed parts crumble.

driverdan 8y ago

Their output decreases but they don't "wear out." This motor requires such little power a small solar panel would work for a very long time.

walrus01 8y ago

Modern high quality monocrystalline silicon PV cells, 156mm size, are commonly warranted for 80% or up to 84% of their original STC rating, after 25 years. PV cells definitely do degrade, but in terms of spinning a nearly frictionless thing in a vacuum, if a 5W rated single cell degrades to 2.5W over 75 years of being exposed to direct sunlight inside a glass vacuum jar, it's still way more than the required energy to keep the thing spinning. Here's an example of a 30 year warranty for a fully assembled module (60 or 72 cells encapsulated in glass and back film), at >80% after 30 years. http://www.jasolar.com/uploadfile/2018/0518/20180518093724135.pdf http://www.jasolar.com/uploadfile/2018/0518/2018051809372413...