I am experimenting with use of the hot California summer sun to cook and to treat water. I am trying to create a solar cooker that deserves a spot in my BOB and one that merits inclusion in my car kit.

Some resources:

Using the sun for emergency preparedness
http://www.earthtoys.com/emagazine.php?issue_number=03.04.01&article=solarcooking

Solar cooking for campers
http://midtown.net/dragonwing/col9907.htm

Improvised solar cooker ideas:

http://www.energyquest.ca.gov/projects/solardogs.html

http://www.hunkinsexperiments.com/pages/potatoes.htm

http://www.reachoutmichigan.org/funexperiments/agesubject/lessons/handouts/solarbake.html

Great idea - use the power that's available.

TRO

My favorite idea for a solar cooker that's easy to transport and set up is the "Sunbrella". Essentially it's an umbrella with a highly reflective underside that, when open, creates a parabolic reflector. It's light and it's compact when folded.

Unfortunately, the weak link in that idea so far is the reflective surface. Highly reflective surfaces tend to crinkle and in other ways become less reflective as they are continually folded and deployed.

Solar cooking is slow, does the solar cookers you are looking at get water hot enough to boil in a realistic timeframe, if at all?

I like playing with solar stuff, but I would think a wood fired water boiler would work better, be more reliable, work all times of the day or night, be easier to pack (less space) and without question get the water hot enough.


Solar is fun to play with, but when it hits the fan, I want my Thermette for water boiling.

BobS, I want your Thermette, too. I think it may be a great companion to a solar oven for the reasons you cite: when you are in a hurry, at night, and when there is little sun.

A thermette is pretty bulky, too. Folding solar could give it a run for its money.

Almost all solar ovens can at least pasturize water [?160 degrees?]; better ones - and that's my goal - can get well over 250 degrees.

Plus, unlike a Thermette, solar ovens can do their thing unattended for hours; do not require finding, igniting, or expending fuel - ever; and do not advertze your presence like a fire either while in use or after you have moved on; and can be built from found materials. They probably could make a mean signal mirror.

All of those virtues convince me solar is worth experimenting and investigating as another layer of redundancy and self-sufficiency.

I was not dissing solar fired cooking. I have little experience with it for cooking. We did it some years ago when I was in boy scouts. But from what I remember it was a very slow process. We used it for cakes and the like (no meat or bacteria critical things) and I remember the cakes were not always cooked well despite being in the sun a long time. Being growing boys, this did not stop us from eating it.


It’s hard to know when water reaches 160 degs when out in the wild, boiling on the other hand is very easy to see.

I have all the material for a small (2 ft by 4 ft) solar water heater that I plan on building this summer to play with. But I don’t plan on cooking with it, just heating shower and clean-up water while camping.


If you are interested, here are a few solar cooking sites I have bookmarked with lots of ideas & plans.

http://solarcooking.org/default.htm

http://www.cookwiththesun.com/solar.htm

http://www.knowledgehound.com/topics/solarcoo.htm

Solar has potential to emerge as a major water purification technology and the industry has developed a reusable indicator that turns color when pasteurization temperature is reached. It is described in this article, among other things:

http://solarcooking.org/sunandwater.htm

Also in solar cooking’s favor over a Thermette: little danger of starting a fire; no fire permits to get or pay for, use almost anywhere – even where fire would not be permitted or welcome; no embers to extinguish or worry about failing to extinguish; and baking capability. Like most new ovens, you have to learn how long to do what for best results.

“Solar baking tip: A conventional oven cooks from the bottom up. A sun oven cooks from the top down. To make sure that your bread, muffins, or pizza isn't too moist on the bottom, preheat a heat sink in your solar cooker, for an hour or so, before you plan to bake. A heat sink is a brick, a tile, or a flat rock that is painted black. The heat sink gets hot in the cooker so you have a hot surface to later place your baking.” http://www.solarhaven.org/SolarCooking2.htm

Thanks for the recipe sites.

Here’s an interesting site on solar food dehydrating:

http://www.geopathfinder.com/9473.html

Solar cooking can be very efficient. I saw one once which used an array of mirrors focused at the bottom of a cast iron frying pan. Could over fry an egg to a crispy state in under 60 seconds.

It was by no means portable however...about the size of a big bath tub for lack of something better to compare it to.

There is a range of "portable" solar cookers ranging from fold-up to suitcase models:

http://65.108.108.197/catalog/solarcookerskits-c-1.html?osCsid=175170b8962102b1cfd38c77657d5c59

Here's a compact solar water purification unit:

Aquapak water purification system with built-in WAPI $20
http://65.108.108.197/catalog/aquapak-p-37.html?osCsid=175170b8962102b1cfd38c77657d5c59

If your bug out or other travel is at night, and you are going to hole up during the day to sleep, eat, and minimize detection, then a solar cooker might be a good fit. If your day will be spent hunting, fishing, and foraging away from a base camp or survival retreat, then a solar cooker makes good sense. Edit: except in bear country I guess you might want to use unattended solar for purifying water only.

I don't think I'd use solar for purifying water. I'm sure all your weather varies but here the sun can't be counted on for something like that.

I guess it could do as an alternative to making a fire but having to carry it but not always being able to use it would make it a liability to me weight wise.