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Comment by 0xbadcafebee | Hacker News Reader

DIY grid-tied residential solar+inverter+battery. Trying to design the solar arrays' tilt mechanism now for lifting/lowering 5 panels at a time in winter (60-degree winter angle, 35-degree spring/summer/fall; ~24" difference). Thinking either two linear actuators, or a single hydraulic jack connected to multiple support beams. The weight isn't much, but I want a way to lift entire top edge at once to prevent twisting. Linear actuators are slightly more money and easier to build, but require power and weather-proofing. Jack is cheaper, but more complex to distribute force. Wondering if there's other options. (winch would require more robust/taller rear posts, seems more complex, might shade rear array)

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Tilting them vertical or nearly so is very useful if there could be any hail, that might be a good idea to support.

What about compressed air? It might not be too hard to find a small brushless low power air pump that could drive pistons directly.

You could mount the pump controller onto the back of the panels and use an accelerometer to measure angle, and run the pump until it's where you want it.

You'd probably need to do some testing and make sure it couldn't get jammed, then build up pressure, then suddenly unstick and move unsafely.

Nice, I started with 5 panels (450W each) and a simple design of interchangeable long and short rear legs to adjust the angle of each panel. Base of leg sits in a bracket on a steel frame, and pivots on an M8 bolt. Top of the leg attaches to some angled 'meccano' steel I affixed to the rear of the panels. It worked great, but I slightly over optimized by sharing legs, which made the twice a year switchover a bit tricky, since I could only manage to lift a single panel at a time.

Last year the 550W panels here dropped to 90eur, and so I just added some more panels to remove the need for the switchover. I saw last week 600W panels going for 80eur but no space left, but tempting. Good luck! It's a nice feeling to have energy independence.

"Projects With Everyday Dave" has done quite a few tests, and may be worth a look:

https://www.youtube.com/watch?v=I-Fz5T5c0OQ

Best of luck =3

Thanks! And I've seen Dave's tests. Since I don't need a fixed angle, do need to maximize production (due to a limited sun horizon), and only have 10 panels, the best option is adjusting angle during winter. The N-S orientation is a really poor performer. (Notice that his test is 30-degree tilt vs N-S; 60-degree tilt will provide 20-25% more power than 30-degree at my latitude, without even considering bifacials w/snow. The only thing that would produce more is an active tracker, but I've got other things to do, and a December deadline...)

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