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Comment by sandworm101 | Hacker News Reader

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 worth the extra complexity of moving parts. I'm thinking of rigs like this: http://www.builditsolar.com/Experimental/Reflectors/Reflecto...

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I've had a rooftop solar system on my home for about ten years ago. I would have never considered an active tracking system, as the wind would have wrecked it long ago. The only maintenance I have to do is, at most, to hose the panels off about once a year.

If you're trying to build out solar in a location where space is at a premium, you're doing it wrong.

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.

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.

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 summer and winter.

> 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.

The efficiency benefit is great, but the extra cost of a rotating frame in 2015, after years of panel price reductions, may end up being more money than just adding extra panels.

Cool link! But would you add a motor and microprocessor to assist with the monthly angle adjustment, please? :p

Seriously, this is a new idea to me. It looks like the chief weakness is it doesn't really help in the winter, which is exactly when you need the most efficiency.

Yes, you must size your panels for the worst case, not the best case.

When it's overcast, the best position is pointing straight up, eg fixed at the correct angle for that latitude.

To put it another way, a tracker optimises your panel in sunny conditions, which is not worth doing. That's when you have a surplus of charge.

That's a good point. For a given deployment site, it might still be worth optimizing for sunny conditions though - depending on the number of sunny days and their distribution across the seasons, the availability/cost of storage from one sunny winter day to the following overcast day, and whether or not you care at all about peak output.

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.

So your rig will generate absolute zero in the middle of the day when the sun is above your head.

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