Differences in solar cooking, different results/issues

[MrZync]

You are quite correct. This is a great example of basic thermodynamics. Heat is always transferred from a hot area to a cold area. So by having the pot on a rack, the net result is less heat transfer into the bottom surface of the oven. Conventional ovens use racks for the same reason. We do not place our baking dishes on the floor of a conventional oven. Of course the heating element would be in the way as well. Excellent observation!

[bg0821]

A rack is a good thing. With the heavens flame oven I built I use a rack and when the oven is tilted to the sun I counter tilt the rack to level the liquid in the pot. I would say always use a rack your food heats up quicker in the pot and would be just that much quicker to get done. I once placed a tile in the oven like you stated but went on to lining the oven with sheet metal painted black which retains heat well. at first the walls had aluminum tape on them until I went to black instead.

[solarcookingnut]

When I got ahold of some tiles from a friend who works construction, I couldn't wait to paint them and put them in the oven to see how it went. The temps held longer, and even an hour after the sun was gone, when I went out to check the oven, the tiles were STILL radiating heat out. Really surprised me. Racks are essential for the average solar cookers success, I know from my own experience and others. thanks for the comment!

[99cachorro]

you are right. Heat cannot be allowed to dissipate into the bottom of the oven. All energy that comes into the oven minus the heat dissipation is the temperature you will have in your oven. This means a non-conductive spacer in the bottom with a black metal piece to transfer all the heat to your cookpot. Also 2 layers of glass is a must to retain heat from any breeze that can suck heat from your oven. GOOD JOB SOLARCOOKING NUT!

[solarcookingnut]

I use several layers of plastic for my nesco cookers window. I don't have problem with any wind or breezes much, only when the seasons change or a storm is coming through, its pretty still here. Thanks for the comment!

[thejesters1975]

Thanks for the info.I didnt know humidity was a factor,but I guess that makes sense.