I have worked on the design for a low tech solar concentrator for a couple of years.
Basically it is time based, turning at 15 degrees per hour with the axis of rotation coresponding to your latitude and pointing at the nearest pole. ( Very similar to how telescopes are moved to track the sun or stars). Something like that needs to be very robust or a sudden gust of wind will grind your gears to a pulp.
So I made things called dripper trackers that are immune to wind damage. The latest version of dripper tracker is called the liquid piston tracker. There are lots of ways of making the timer for it but electronics are beyond my skill levels. The mount will work with solar panels (No concentration so easiest to set up) or as a solar cooker or stirling motor mount, Concentration of light IS involved with these so my design shows 2 half dishes which solves a difficult moving center of gravity issue caused by the seasons.
In the video, I show a model of the mount set up for solar concentration and also show how the liquid piston idea works.
http://www.youtube.com/watch?v=0-bj0guW0k0 There are other videos too but this one shows the liquid piston idea best.
The link below is a diagram of the liquid piston tracker idea. (There are many ways of doing this but this diagram shows it most simply, I think. Feel free to do the timing any way you want )
http://solardesign.ning.com/photo/liquid-piston-tracker
I made some dripper trackers in the past (almost the same thing but less accurate). They were much more stable in wind than I expected.
(All my stuff in patent free) and if you wish to share your results, you can add it to the solarcooking wiki on their tracking page.
Brian
Thanks - that looks like some pretty cool stuff you’re doing. The liquid piston idea is interesting, although a geared motor is probably more practical for most applications. A satellite dish positioning motor is good for large dishes.
Ironically, I’ve just come down from our roof where a friend and I have been installing a new evacuated tube water heater. These units are so efficient that they can get hot enough to boil water in summer, but it sure will be good to have free hot water all year…
Thanks MichaeIN. I do not think the geared motor is more practical. What happens when it gets a big gust of wind? I think the gears will get mangled. And it has to be geared down so much! The thing is hardly moving. With the liquid piston, there is nothing to mangle. And the viscosity of the water or fluid very quickly damps down any movement you get. Next morning, all you need is a 12 volt bilge pump and you send the water back to the top container in 4 or 5 minutes. My bilge pump cost 20 dollars. I do not know the best way to do the timing or valve controller, there are dozens of choices there! But that might be a 20 dollar deal too.
I hope it brings out your inner Mcguyver! I am sure it can be done and I am pretty sure nobody has done it this way before.
Why not be the first person in the world to do it?
Nobody will care right now, but in 20 years you might be famous for doing it.
Brian
MichaelN:
Thanks - that looks like some pretty cool stuff you’re doing. The liquid piston idea is interesting, although a geared motor is probably more practical for most applications. A satellite dish positioning motor is good for large dishes.
Ironically, I’ve just come down from our roof where a friend and I have been installing a new evacuated tube water heater. These units are so efficient that they can get hot enough to boil water in summer, but it sure will be good to have free hot water all year…