DIY Solar Oven

Quick update,

We baked large potatoes today.

If you can cook well, large potatoes, it means your solar oven has enough energy to cook just about anything.

This little solar oven, made from a common cardboard box, insulated by straw and a few old clothes and using common car sunshade reflectors can do amazing things, and anybody can put one together at a small cost.



Kostas

Continuing to test this little cardboard box solar oven...today we cooked chicken.

Here are the results



Kostas

Hello to All !!!

I realize that there are some people that might have a hard time getting straw and/or many old clothes, so I tried using pine needles for insulation...for some folks they might be more readily available.

They worked just fine.

We baked bread and a good size meal of goat meat and a few potatoes.

It seems remarkably easy to do solar cooking...I don't know what took so long to get here.

If anyone tries this I would like your experience with this and suggestions.




Kostas

This is relevant....

Nytimes....pellets

Burning our own home...

Kostas

Hello, everyone!

Regrettably, the weather hasn't been cooperating for solar cooking recently.

During a leisurely walk in my neighborhood, I couldn't help but notice the discarded items we often overlook.

It struck me that from these very materials, we could fashion approximately seven or eight solar ovens.

Utilizing old clothes, pine needles, or straw as insulation, we can create these solar ovens with ease.

It's a simple yet effective solution.

Kostas

Very solar warm stuff there :-)      I run a solar cooking group on MeWe  we have lots of great ideas there as  well.


Other things you can consider is using objects like trash cans to block the wind to help hold the heat,  I have found making barriers to stop the wind most helpful.


Painting jars flat black with a strip of masking tape on them then removing the tape afterward makes a good cooking vessel as you can see where you removed the tape how well the food is cooking.


Great job using the sun!

Mart,

This is a good opportunity to sort of summarize the objectives of this solar oven design.


Cost-effectiveness: The solar oven should be designed to be low-cost, ensuring affordability for people with limited financial resources.

Ease of assembly: The solar oven should be simple to assemble and require no specialized skills such as carpentry or welding. It should be easily put together by individuals with no prior experience or technical knowledge.

Utilization of local and inexpensive materials: Whenever possible, the solar oven should utilize materials readily available in the local surroundings, minimizing the need for expensive or hard-to-find components. For instance, instead of constructing a wooden box, a cardboard box obtained from recycling can be used. Insulation can be achieved using old clothes, pine needles, or straw.

Household items for cooking: The solar oven should be compatible with common household items that can serve as cooking vessels, such as a metal pan, reducing the need for additional specialized equipment.

Locally sourced and cut glass: The solar oven should utilize a piece of glass that can be purchased locally and cut by a nearby glass shop, ensuring accessibility and convenience.

Alternative reflectors: To avoid the expense of using glass as reflectors, the design should incorporate affordable alternatives, such as reflective material commonly found used in cars to keep the sun out; they are not expensive.

Minimal user intervention: The solar oven should require minimal user intervention during the cooking process. The cook should be able to set up the oven and leave it unattended for the next three to four hours. Constant adjustment of the reflectors should not be necessary, allowing the cook to engage in other activities while the food is being prepared.

Capacity for cooking whole meals: A crucial objective is to ensure that the solar oven has the capacity to cook complete meals for an entire family. It should be capable of baking whole loaves of bread, rather than only small pieces, enabling the preparation of substantial portions of food.

The individuals who are expected to benefit the most from this solar design are those belonging to the Third World, who currently rely on wood for cooking and lack the financial means to buy solar ovens available in the market.

There is an added important benefit. The carbon footprint of this design is small compared to a factory produced solar oven that needs to be manufactured and shipped from far away places.

Kostas

Yep that is the goals of most solar enthusiasts....  

Let me give you links to two excellent solar web sites.        Sharing ideas in an open source manner is awesome.


Solar cookers from around the world ->

https://solarcooking.fandom.com/wiki/Solar_Cooking_Wiki_(Home)


This site shows solar projects that people who love to play do.        

https://www.builditsolar.com



These two sites have really helped me to see new ideas of how others use solar to cook, heat water, and make electricity.

Both are excellent sites Mart.

Thanks

I’ve made one before at a workshop we did locally.  Don’t have pictures, unfortunately, because someone threw it away by mistake.  Easiest and most economical way is to get two cardboard boxes with lids, should be sturdy.  One needs to nest inside the other so 2 inches of insulation can be put on all sides except top.  Straw works well, or crumpled paper.  Cut off lid on bottom box.  Add insulation material to bottom and pack it fairly tightly, inserting inside box afterward, then packing insulation evenly around sides.   Line lids of top box with aluminum foil or some reflective material and arrange so it is at an angle to the sun for best reflection back into the inside.  You will have to tape it to hold it in place.  You may want to use larger pieces of cardboard instead of the lids off the box, to get a larger reflective surface, or use galvanized sheet metal.  Inside dimensions should be large enough you can put a covered dark colored pan inside to cook in.  Cast iron works well because it has thermal mass and can retain more heat.  Use a clear lid on top of pan.  Or use Corning ware.  Works best if pot is dark or black as it will absorb more heat.   On top of the box,  use a plexiglass cover or glass cover just large enough to fit snugly over the top and the lids still be in a position to reflect sun back into the pot.  Recycled window pane works well.  The foil or galvanized metal or tin should extend down into the inside box to reflect heat back onto the cooking pot.  Gets hot enough to cook meat or veggies, rice, etc., but may take several hours on a sunny day.   Check with thermometer before actually using for cooking, and you may want to keep a thermometer inside on top of your cooking pot to monitor it.   May not get hot enough to cook pork.  

I think someone who is creative could build a permanent stationary one perhaps out of bricks or something similar, line with the insulation, inner wall of perhaps a recycled stainless steel box or sink, and do a glass, or plexiglass top and maybe large galvanized metal reflectors.  

Very interesting Faye...
It's a good description, but it would help if have photos and a vid.
Kostas

they are excellent sites

i agree

kostas

Someday when I get around to it I'm going to build a modified version of this solar oven. I think it is a great design. I'll just extend the collector a bit lower so I can make the oven a bit more rectangular.

Here is a sol oven from a discarded plastic crate, straw, some old clothes etc.

Kostas

Mr. Karoubas,
Thank you for your descriptions and videos . I could replicate a solar oven made out of cardboard box, old clothes and aluminium foil. I used a stainless steel pot with a glass lid as my container. I could succesfully cook potatoes. I also tried bread, but on this day i was late to start, so only the outer crust cooked. If i had started early in the morning, i am sure the bread would cook well, too. I am in Izmir, Turkey, so the climatic conditions were very similar to yours. Next time, i will increase the surface area of the reflectors. On my first trial i only used the lids of the box.