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Gravity-Powered Solar Tracker

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21–30 of 33 posts

Re: Gravity-Powered Solar Tracker

#21
post #19

Earlier quoted context omitted.

This system doesn't seem very expensive or difficult to repair. And in any case, the worst-case scenario is that the solar panel becomes static.

The worse case scenario is that the panel breaks. Is the framework actually designed to handle the weight of the water?

I would presume so, as that is what it has been designed to do.

Re: Gravity-Powered Solar Tracker

#22

Anything that moves will one day break. I hesitate to move away from the reliability of a static panel. Adjusting the drip rate in this scheme would also be constant battle of weather, temperature and season. You'd never get it perfect. Compared to a simple solar setup it may be more efficient, but compared to more complex, yet still static, combinations of a panels and a reflectors I don't think the improvements are…

If you can afford to get more panels than strictly necessary, this solution isn't very good. But I guess for households in poor countries it could really help.

Re: Gravity-Powered Solar Tracker

#23

Anything that moves will one day break. I hesitate to move away from the reliability of a static panel. Adjusting the drip rate in this scheme would also be constant battle of weather, temperature and season. You'd never get it perfect. Compared to a simple solar setup it may be more efficient, but compared to more complex, yet still static, combinations of a panels and a reflectors I don't think the improvements are…

Yes, tracking has got to be super-simple. Flowers do it; maybe one day we'll use them somehow. Flower power. But the efficiency difference is dramatic, especially for monocrystalline. I got full power in the middle of winter near sunet (4pm) by tilting the panel almost vertically. Consider the effect of solar ray incidence on Earth: it's why the tropics are hot and the poles are cold. It's the difference between summ…

> Yes, tracking has got to be super-simple. Flowers do it; maybe one day we'll use them somehow. Flower power.

Flowers are not simple. They're insanely complex devices built entirely by and from nanomachines. We're barely beginning to understand what's going on. For instance, we found solar tracking to be a set of clever photochemical reactions that respond to particular wavelengths and disrupt the natural growth of the plant in such a way that it follows the sun. Mind you, that we know about those reactions does not mean that we actually understand them in perfect detail.

Nature only looks simple. In fact, the levels of its complexity are so great that for the most of mankind's history we didn't even suspect what's going on.

Re: Gravity-Powered Solar Tracker

#24
Ah, before I read the article, from the image I thought maybe it was bottles on both sides, and using the sun to evaporate the water in the lower bottle until it reaches the higher bottle, causing it to tip. Thought that was pretty clever! But probably not accurate. Would be beautiful to design a closed system that works well like that however.

Re: Gravity-Powered Solar Tracker

#25
post #18
post #3

Earlier quoted context omitted.

Another mechanical approach that is relatively cheap and doesn't require refilling bottles is to use a closed system of a hydraulic cylinder and two exposed freon tanks, one facing east and one facing west: http://www.motherearthnews.com/diy/solar-tracker-zmaz77ndzgo... These mechanical approaches are generally awesome because they hold up well in bad weather. If you wanted to go all out I don't see why you couldn't…

What about an array of photodiodes like this: o o o o X o o o o This is in an enclosed box with a hole over the center. Here, "o" represents a photodiode and "X" represents the center of the hole. When the solar panel is pointed directly at the sun, the sun is at position X and no photodiode is lit up. As the sun changes position, eventually it will light up one of the photodiodes. That completes a circuit which uses…

Good ideas!

I had in mind a purely mechanical mechanism that takes the linear motion of the hydraulic piston or the water clock and turns it into a parabolic movement. I'm a software guy and could not find such a mechanism easily on Google, though.

Re: Gravity-Powered Solar Tracker

#26

Anything that moves will one day break. I hesitate to move away from the reliability of a static panel. Adjusting the drip rate in this scheme would also be constant battle of weather, temperature and season. You'd never get it perfect. Compared to a simple solar setup it may be more efficient, but compared to more complex, yet still static, combinations of a panels and a reflectors I don't think the improvements are…

I worked about a year in a project to design a solar tracker and we pretty much came to the same conclusion.

We hit several obstacles but in my opinion the two main reasons for the failure of the project were:

1. Safety: We underestimated how a lack of regulations left us in a legal limbo

2. Reliability: We underestimated how quickly outages and repair cost eat the profit

I don't say it's impossible, other companies (like Solon for example) sold single and dual axis trackers back then and they are still selling them today. Our design was much simpler than the existing solutions and we still ran into the reliability trap.

Re: Gravity-Powered Solar Tracker

#27
Actually there is a simple mechanical gear that can translate constant speed rotation into a perfect two axis sun tracker. If you'd combine this with the contraption from the article you'd get a gravity-powered two axis tracker.

Re: Gravity-Powered Solar Tracker

#28
Actually there is a simple mechanical gear that can translate constant speed rotation into a perfect two axis sun tracker. If you'd combine this with the contraption from the article you'd get a gravity-powered two axis tracker.

Re: Gravity-Powered Solar Tracker

#30
post #2

A human has to refill the bottles.

i think analogous from your observation could be: fill water bottles once in the morning or additionally use mind, motor skills, and body, lose the free use of a hand, resources to wave a fan in front of your face all day;

Or, humans use electronics and motors because it actually is more efficient than getting a human to do the work.
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