DIY tracking solar accumulating barbecue is within reach!

Paraffin wax may be a good way of storing heat because you get the latent heat of melting (solidifying). Otherwise if your main requirement is domestic heating: water has the highest specific heat capacity of any substance.

I don't suppose you have a web reference that validates the suitability of materials for the purpose of heat storage. I am hoping to find a material that is suitable for storing a lack of heat - some kind of eutectic fluid perhaps - that will maintain a low temperature for long periods.

Was looking to maintain a temperature of +4^oC so I guess water would be the obvious solution

Not sure why people wandered off into the woods to check out cold stuff. Just a little irrelevent to the thread, i think. Anyway, a guy in the USA offered to do a nice diagram of the low tech dripper tracker and it is at http://solarcooking.wikia.com/wiki/Tracking My ugly drawing of the clock based tracker is lower down on that page too. Either tracker is probably relevent to solar panels as well as to solar cookers. From what I read, tracking improves the output of solar panels by at least 25% BUT tracking is usually too expensive to be worth it. These trackers are really cheap. My biggest failure in making the accumulator was the reflector. I didn't make the kitchen foil smooth enough. Anyone know if mylar is stretchable? Brian

The tracking solar accumulator was an attempt to design a fairly simple mount for a parabolic dish solar concentrator. So that it could track the sun and keep the concentrated light on one spot.

I tried out the first model a few years ago, and it had several issues but just making it helped a lot. Over a season, the adjustment brought the center of gravity more and more out of whack and made it much harder to turn the thing. Then, late last year or early this year, I thought of 2 parabolic dishes on equatorial mount. The seasonal movement of one would counterbalance the seasonal movement of the other so that the thing would be easily turned throughout the year.

I put models on the web but nobody really was interested. I really thought that someone would make one. Anyway, they didn't so here are links to my first demo model of this year. It is only half built so far and I hope to complete it this month.

It will have one dish and 1 or 2 counterweights

http://www.youtube.com/watch?v=5OqG2LesnSo is video and http://www.facebook.com/album.php?aid=278164&id=736625766&l=8b34cdb5e0 is a photo album about it. (It gets updated as I built it)

gaiatechnician, have you thought about using a small photo voltaic panel placed in the shade behind the reflector. When the sun hits the panel it drives a motor which is geared down by a lot and used to turn the whole assembly, so that, the panel again returns to the shade.

Seen from above:-

clearly the pivot point needs to be under the centre of gravity of the reflector and oven assembly.