Thread

1. nbf_1995 · 1790086541 · focus · HN ↗

   It seems like it would be more effective to simply put all the solar panels in a field, and construct a cheap shade over the entire canal no? The supports in the picture are massive and don't look cheap. Also I would imagine the solar array uses more copper than a similar capacity array just built in a field. You can't daisy chain multiple miles of solar panels together, so you need an extra power line to run alongside the whole thing.

   Put the solar panels in a field: The solar array uses less copper. The shade supports don't have to hold up solar panels: Shade supports cost less.

   The best reasoning they give is that California has insane permitting requirements, and it takes 1/6 the time to build on developed land compared to undeveloped land.

   1. sophacles · 1790110708 · focus · HN ↗

      Power lines are made of aluminum and steel.

      I seriously doubt that you can chain even 1/4 mile of panels together without destroying things. Thats already puting thousands of volts and hundreds or thousands of amps through the silicon. If you are making it all parallel you still need wiring between panels that can handle that. The cabling doesn't go away, it just moves.

      Wouldn't there still be supports in a feild of solar panels? Are you sure that those supports + the supports for the shade material are going to be less material than the supports for this?

      Most shade material wears out pretty quickly. Will their replacement result in more expense, more waste, etc than just putting the solar panels?

      Shade material is generally pretty heavy, is it really going to need significantly less robust support? Weight aside, how much of the load those supports are rated for is due to the actual weight of the panels, and how much is for forces from things like wind?

      1. lightedman · 1790110964 · focus · HN ↗

         "Thats already puting thousands of volts and hundreds or thousands of amps through the silicon."

         In a typical string of solar panels design, you'll get tons of volts but not a lot in amps - current cell maximums top out at ~11A and the connective MC4 wiring can't handle too much more current than that, so what you end up with is like a 1,000V 10A string on one MPPT connection into the inverter.

         1. sophacles · 1790112210 · focus · HN ↗

            A solar panel is 4 feet or so on the long side. Theres 250+ of them in a string 1/4 mile long.... at 48 V/panel, you get to 12KV. even if it's topped out at 10A thats still 120KW... you need a hefty cable to carry that panel to panel. Which is the core of the point I was making.

            1. lightedman · 1790176963 · focus · HN ↗

               "Theres 250+ of them in a string 1/4 mile long.... at 48 V/panel, you get to 12KV. "

               And they're never installed in config chains that high voltage - cell spacing between cells is typically very low and only capable of withstanding ~5kV before internal arcing occurs.

               Also, your typical 72-cell solar panel is only 32V.

Unofficial Hacker News client; not affiliated with Y Combinator.