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Non-toxic, easy to make, affordable solar oven?  RSS feed

 
master steward
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Anyone know of any easy to make, affordable, non-toxic solar ovens? The one my son wanted to make was easy and affordable, but certianly NOT non-toxic!

A bit of history: Two days back my 5 year old asked me a question about how the sun can cook things. So, we watched a video about how to build a box-style solar oven (https://www.youtube.com/watch?v=v5CdNH3sQT0). And, then, of course, he wanted to make one just like in the video.

We already had the styrofoam from my husband's fishkeeping, as well as aluminum foil, plexiglass (also from said fishkeeping), and cardboard boxes. We bought some metal tape yesterday, and made a solar oven.



He loves his solar oven!



And, of course, he wanted to cook an egg in it, just like in the video. We got the oven up to 190 degress F today, and cooked an egg!



The problem is, of course, the egg tasted like aluminum tape and styrofoam. Pretty sure we DON'T want to be ingesting any more of that, though a few bites made for a good secience eperiement.

Long story short, do you know of any really easy, affordable, reasonably-effective and non-toxic solar ovens that my son and I could make?

Thanks!!!

 
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In the short term perhaps you can cook in it with lidded cast iron to keep contaminants (most of them at least) out of the food?

I wonder if a clay box (possibly darkened with a bit of charcoal) would work well for the oven itself (considering it's mostly a dry season tool in our region) and the reflectors could be mounted outside only? Might increase cook times but it's only a planning cost rather than an energy cost.
 
pollinator
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That tape and styrofoam is noxious stuff when warmed! Dont ask how i know, i dont want to think about it!

I have seen straw used, wool could work, sawdust. Plain steel coated with lamp black is a good servicable box as is wood, tempered glass (think old thrown out stereo cabinet glass) is tastier and dont do meat kebabs without a pink filter. Reportedly meat usually tastes terrible when cooked in direct rays.

You could look up african seminars on the topic for great use of natural materials. Mirrored lexan is a great reflector and no need to make the inside reflective with good insulation and reflector design.

Home power magazine has had hreat articles on high tech and safe solar ovens.

There is an evacuated tube oven that i have seen on permies and around the web.

Id go wood, straw metal and glass and detail it like siding on a house so it can be outside.

Im with you, i do not have one because paint, polyisocyanurate foam, teflon, plastic.... the usual suspects.

We have a wood framed concentrator from a projection screen tv that i use to make coffee sometimes. I built a small stand for the cup, made from a chromed shoe display shelf and some wood. The concentrator (magnifying lens) has a stand that is almost finished. I have been just propping it up for now. The sun is focused on the mirror from the same television, (they are extremely high quality mirrors) and then up onto the bottom of my campfire blackened stainelss, oversized backpacking mug. Works like a champ, never fried anything though.

I wouldnt focus to a fine point on the surface of the mirror as it could cook the reflective backing off or even break the glass.

Saw this on greenpowerscience youtube channel. He used livestock wire fencing built as a tabletop to hold a pan and the rest is the same.
 
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For insulation, Stuff between the boxes with crumpled newspaper or straw.

Use flour and water paste or white glue to secure the foil.

recycle old window glass for cover.

Best,
Lil
Reed Urban Homestead
 
pollinator
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Nicole, use that or another cooking pot as the heater. Glass should sit on the rim. Any insulation/tape/ickiness will be on the outside away from food.

Once you grasp that concept it's easy. You could set that pot in another pot, insulate between with anything(hay, dried grass).  Easy to assemble or dissassemble.
 
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We built them at school with foil instead of aluminum tape, and we used duct tape to hold things in place. I'm not sure how much less toxic it was, but no one tasted aluminum in their food.

The boxes were not well-insulated but did get warm enough to melt cheese. One family told me they put their box in the car on the front dash the next time they tried it. That definitely got the temp up and they had good luck cooking

I tried one from a styro box. I cut an opening in the top and covered it with glass. I also taped a piece of glass to the inside so the opening was double-paned. I don't remember what I used on the inside - it may have been lined with foil on the sides and a piece of black construction paper on the bottom. Or I may just have used the paper on the bottom and left the sides as they were.
 
pollinator
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Try cooking inside a canning jar placed in that oven. It will kick the temps up a notch as well as prevent the toxic goop from ruining the food. Keeps the bugs out too. Works good.
 
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Probably not so easy to do, because it would need to be fired, but I would think the best type would be of clay. Make the inside shiny with a glaze, and the outside rough like bricks. Ever felt a red brick wall that has been in the sun? They get super hot. So that would certainly warm up your clay oven. I'm not sure how you would manage the reflective part on the top, but perhaps that could be made with just a metal sheet, or foil on card, without any styrofoam.
 
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Awe, that's so cute.

Hey I remember watching a youtube video a while back, something to the effect of "six cool things you can do with a used satellite dish".

One of those things, the satellite dish which is curved to catch radio waves, is also a good curve to catch sun light. This guy tinfoiled over a satellite dish, and cooked something (I'd have to say it probably was an egg but I don't recall).

I see those things thrown aside all over the place.
 
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Nichole: Don't know if you have built a new cooker yet. I was looking up to show you how to build the type I like, and hit this link:  The 4 Types of Solar Cookers looked at it, and said wow, that is probably the best write up of types I have ever seen. There are links at the bottom for videos of making them. I'd suggest look at it, see which type you have stuff around for, and then look for the right video for it. What I have underfoot to build with is different than what you do, and what your kids can handle is different than what I can on a child free property. LOTS of cool info on that page! There's bound to be one you get along with easily.

Be sure to use sunglasses near solar cookers, they can be really damaging to the eyes.

Michael Sohocki wrote: Hey I remember watching a youtube video a while back, something to the effect of "six cool things you can do with a used satellite dish".

One of those things, the satellite dish which is curved to catch radio waves, is also a good curve to catch sun light. This guy tinfoiled over a satellite dish, and cooked something (I'd have to say it probably was an egg but I don't recall).

I see those things thrown aside all over the place.


Satellite dishes, with a good deep curve, like an umbrella. Not shallow curved dishes like Dish TV. Those don't work for solar, they have no useful focal point. Real satellite dishes are getting harder to find, I'd like a few, but have not seen any around. They do work nicely. They are on that link too. I have used them as cookers before, but the ones I used were not mine.

A few years ago I moved out of the desert. Out there, solar cooking is SO EASY. 8 months out of the year I rarely used the stove at all. I have used all kinds of cookers, and plan to do a built in type here. I'm a big fan of thermal mass in mine, but I'm not a casual user who is playing with a kid who will probably lose interest soon. And I have different needs, skills, supplies, and safety needs.
That IS a cool link.
 
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