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. walrus01 · 1790110178 · focus · HN ↗

      The cost of building that steel structure that will hold up against maximum in 100 year wind forces isn't cheap. Large PV panels make very good sails. The trusses look basically the same as you'd see in a large agricultural barn, horse riding arena, etc. Putting the PV panels on empty bare land at a height people can walk around and work with would be considerably less costly.

      I would very much like to see a total dollar figure for the example "roof trusses over the canel" structure vs. how many panels it can hold.

      It's already true that the ground mounting costs and labor to assemble the ground mount are a huge part of building a large scale PV system.

      1. asdff · 1790116305 · focus · HN ↗

         You know where the wind blows really damn hard in California? Virtually any open field you can imagine putting these otherwise. Mojave for example is damn windy. That is why they currently host massive wind installations there.

         1. walrus01 · 1790116842 · focus · HN ↗

            I'm well aware of that, thanks. Ground mount PV is still going to be considerably less costly than this. Partly because it's easier to build, partly because it has many competing companies that sell the basic aluminum rail/hot dip galvanized steel mounting pieces, partly because you can use relatively low cost contractors to do work like install its footings and bolt it together.

            Having stuff at ground level that can be reached by people on foot or on a 6 foot step ladder also makes doing the electrical work a lot less costly.

            1. asdff · 1790127662 · focus · HN ↗

               >Having stuff at ground level that can be reached by people on foot or on a 6 foot step ladder also makes doing the electrical work a lot less costly.

               I mean sure, but compared to say having that technician in a dingy boat, its more costly in the sense you need a dingy boat. But this doesn't seem insurmountable. Maybe you don't even need a dingy boat. Maybe just a long 2x12 would be fine or some other scaffold platform you can just drag around. There's also something to be said about this solar array being where the land is already being used, and some greenfield solar array going in, well, greenfield areas that might be ecologically more sensitive.

               1. walrus01 · 1790128420 · focus · HN ↗

                  Tell me you've never built a ground or roof mount PV system without coming right out any saying it... Wow. You took a look at the photos in the original URL and think that a person can stand in a small boat and wire up the backside of the panels? I'd love to obtain some of what you're smoking because it must be some incredible stuff.

                  1. asdff · 1790197104 · focus · HN ↗

                     You tell me one reply up a ground based system can be repaired by a technician with a stepladder and somehow a longer step ladder with a solid platform doesn't work for what is effectively just a slightly taller ground based system? Please explain.

                     1. walrus01 · 1790203651 · focus · HN ↗

                        Have you ever put a stepladder in the center of a dinghy and tried standing on it?
            2. jyounker · 1790181046 · focus · HN ↗

               Part of the point is reducing evaporation.

Unofficial Hacker News client; not affiliated with Y Combinator.