Monday, June 23, 2008

Solar Oh-no.

Well, I, too, tried and failed at using a home-made solar oven (and a bunch of commas there at the beginning, see that?). I was disappointed. Vastly. Deeply.

I started with plans from Backwoods Home Magazine and from Cooking with Sunshine. I used two boxes, lots of foil, black paint, black cookware, double-strength glass, a car sun reflector, and newspaper and paper grocery bag insulation. But no dice.

It looked good enough:

So, bummer.

My partner helpfully stated that my "engineering" was off. I told him where he could take his engineering.

Then - in a much more helpful vein - he promised to help me try it again. His suggestions: smaller boxes. Maybe it's too big of a set-up? My guess is that the space between the two boxes is too large and that they need to be closer in size, that the insulation wasn't cutting it.

We salvaged a big old mirror that we might be able to rig up to a metal box - this was his other suggestion, to try to find a metal box. So we're still in the market for the home-made job. But who knows, with the rave reviews of the readymade product, we may eventually take that option.

In the end the pot of beans and the cornbread were about half done after sitting out 8 hours! I put them in the oven for a while and we still had dinner - it just wasn't as low-tech as I'd hoped!


Hausfrau said...

Sorry to hear about that! When my Dad finally puts his together I will put up info and pictures! Also, if you plan to give it another go - I've read (never done it myself) that it's really key to seek out the good reflective material, I think it's called Mylar or Monokote. I don't know if that's helpful or just more depressing. Hugs!

Hausfrau said...

I think I prefer the Global Sun Oven over the Tulsi Hybrid SO. But the GSO does not fit full size pizzas :(.

anajz said...

I purchased some mylar (emergency blanket)and plan to use that on my next attempt.
Don't give up on your box. The angle of your reflector seems to be vertical, but I think it needs to be at an angle. I was informed today that when I use the commercial oven that I have on order, I won't have to use the reflector during the summer.
Are your pots sitting directly on the floor of your cooker? I read that it needs to be on a rack to let the air circulate underneath. Is that foil on your pots? If it is, that might reflect instead of conduct.
The few successes I have experienced came when I placed the black granite pot with its cover inside an oven baking bag.
After further research, I found that wind does make a difference in a homemade oven because most are not air tight. This has been a true education, and I soon hope to forge forward in my own solar cooking efforts.
We need to all meet at Frau's for some hands-on

Lewru said...

Awesome help! I knew the angle looked funny but wasn't sure what to do about it - I will try to move it around a bit. And mylar. And black covers instead of foil. Check, check, and check! Thank you!

anajz said...

After rereading my post from yesterday, I hope I did not come across as a "know-it-all"..because I am certainly NOT. I am still struggling, and have learn from a few "what-NOT-to-do" accidents.
My new parobolic cooker has arrived and I am anxious to try it out.

anajz said...

Well, gee, two things I forgot to mention before I hit publish. I LOVE the new look of your blog! It is so bright and cheerful!
Also, if you ever get a chance..there is a YouTube user called solarcookingnut. She has several videos about using homemade solar cookers, some of which are from unlikely sources.
We are going to conquer this..I just know it!

Lewru said...

You're right, anajz! We will do it together. It takes a village, even if it's a cyber one! :)
(And thanks for the compliments about the page - those pics are from atop a mountain in Salt Lake City. It's so beautiful there!)

tsponheim said...

Your cooker didn't work because you wrapped the food in alumunum foil. This bounced the light away from the food. Try cooking in dark colored pots with lids.

Tom Sponheim
The Solar Cooking Archive Wiki
Solar Cookers International

Lewru said...

I had the food in black metalware but I didn't have tops for them. I guess it would be better to do it open air?

Frank said...

Question about preparing food..
On low sun days when the sun is in
the southern hemisphere, would it
be a good idea to preheat the food in a microwave before placing it in the sun oven? I am new to this
sun cooking and I have heard that
a preheated oven will lose some heat when food is placed into it.
It seems to me a few minutes in the
microwave to preheat the food would
cut down on the heat loss and also
speed up the cooking process.

Lewru said...

I will refer you to Peak Oil Hausfrau with that question (notice her comment on this page). She is the QUEEN of solar cooking!