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In comparison to keeping the panels clean and cooled in the middle of a desert?

dymk 4y ago
Serious answer? Yes. Brooms and mounting panels a foot off the ground works fine. Heat reduces efficiently but by a very, very small amount. Not long ago there was a company posted to HN which puts panels basically flat on the ground, and has a little robot run up and down sweeping them off in Texas. Much simpler and cheaper and less error prone than a floating array of panels exposed to salt water and waves.
- jnsaff2 4y ago
  Heat reduces power of PV Panels by up to 10%. Looking at a random spec sheet it's -0.35%/C so from 45C to 75C the difference is roughly 10%. I would not call it "very very small". Also increase in temperature reduces the lifetime of the panels. That said I too think that taking that hit will never be offset by all the faff of dealing with ocean water, waves etc. Moreover the big installations in Morocco have not been PV but concentrated mirrors in which case any increase in heat is improvement and brooms are more important.
- jimmydorry 4y ago
  Brooms cause abrasions, especially when they are moving sand along glass or composite plastics. Non lubricated wipers are fine (but not ideal) for dirt / dust, but not at all comparable for sand.
  - dymk 4y ago
    solar panels have been being swept with brooms for decades, it works fine
    - jimmydorry 4y ago
      Yeah, and as far as I am aware, they are all kept clean with water. I'm not aware of a single installation that isn't hooked up to water facilities, let alone plonked down in the middle of a desert.
      - dymk 4y ago
        I'm really not sure why you think washing them with water is vital to make a solar installation worthwhile. Panels have been getting / are dirt cheap, efficiencies have been going up, and that trend will continue for a long time. If $ cost to wash is more than $ increase from cleaner panels, we won't wash them.
donny2018 4y ago
Would panels be even efficient for such a project though? I think concentrated solar is better in this case, as it generates power at night, more stable during weather changes, and not subject to heating issues.

dymk 4y ago

Serious answer? Yes. Brooms and mounting panels a foot off the ground works fine. Heat reduces efficiently but by a very, very small amount. Not long ago there was a company posted to HN which puts panels basically flat on the ground, and has a little robot run up and down sweeping them off in Texas. Much simpler and cheaper and less error prone than a floating array of panels exposed to salt water and waves.

jnsaff2 4y ago
Heat reduces power of PV Panels by up to 10%. Looking at a random spec sheet it's -0.35%/C so from 45C to 75C the difference is roughly 10%. I would not call it "very very small". Also increase in temperature reduces the lifetime of the panels. That said I too think that taking that hit will never be offset by all the faff of dealing with ocean water, waves etc. Moreover the big installations in Morocco have not been PV but concentrated mirrors in which case any increase in heat is improvement and brooms are more important.
jimmydorry 4y ago
Brooms cause abrasions, especially when they are moving sand along glass or composite plastics. Non lubricated wipers are fine (but not ideal) for dirt / dust, but not at all comparable for sand.
- dymk 4y ago
  solar panels have been being swept with brooms for decades, it works fine
  - jimmydorry 4y ago
    Yeah, and as far as I am aware, they are all kept clean with water. I'm not aware of a single installation that isn't hooked up to water facilities, let alone plonked down in the middle of a desert.
    - dymk 4y ago
      I'm really not sure why you think washing them with water is vital to make a solar installation worthwhile. Panels have been getting / are dirt cheap, efficiencies have been going up, and that trend will continue for a long time. If $ cost to wash is more than $ increase from cleaner panels, we won't wash them.

donny2018 4y ago

Would panels be even efficient for such a project though? I think concentrated solar is better in this case, as it generates power at night, more stable during weather changes, and not subject to heating issues.