Solar Cooking??

@Ravenladyj (22936)
United States
June 12, 2007 10:38am CST
So I was reading my latest issue of my yoga magazines and wasnt there an article in it about Sun Ovens and Solar cooking! Now this is something I've never even heard of before today but I have to say that the thought of it really interests me...In the summer here it gets very hot and humid so cooking in the oven isnt somethign I care to do...I do cook in the firepit sometimes and of course we bbq but you're a little limited as to what you can cook not to mention both cost money for fuel to one degree or another....Well from what i"ve been reading you can not only make your own Solar Oven (which I'll be gettign my husband to do for me this weekend LOL) but you can pretty much cook anything in it from stews to breads and so on.... Has anyone else heard of this? Does anyone here solar cook? If so what tips could you provide if any? :-)
3 people like this
13 responses
@brokentia (10395)
• United States
12 Jun 07
I have not heard or such thing. But I wanted to say thanks for passing on the knowledge. I will have to look into this. Even though I doubt I could get my partner to make me one because I barely see him...he works a lot. But it would be very interesting to know for future reference! :)
@Ravenladyj (22936)
• United States
12 Jun 07
WEll ya know..it actually looks pretty damn easy to do really..so if my husband flakes on me I'm gonna make it myself....the one link has instructions for different types of solar ovens, you should check it out..looks pretty simple...I think LOL
@mssnow (9493)
• United States
2 Jul 09
Here is an article on solar panel cooking have a look http://www.squidoo.com/solarcook
@mssnow (9493)
• United States
12 Jun 07
Solar ovens are easy to make. When i get to Arizona i plan to make one and use it daily so i am not using g electricity. to cook. Also it wont heat up my house. so that will save on electric for the air conditioner. I also plan on hanging my clothes to dry outside. let the sun dry them. i do that here in oregon in the summer time. I love sun dried clothes. I am looking into other ideas to use the sun as well.
@Ravenladyj (22936)
• United States
12 Jun 07
Yea I told my husband we're putting up a clothesline again...utilities are just too bloody expensive here in NY its nuts! He's concerned about the dogs (thats why we took the first line we had down...LOL the dogs kept snatching clothes off it and runnign around the yard with them LOL)..but I'm willing to try again..We dont have A/C so it gets pretty damn hot in this house and I'm not goin through another summer like that plus it'll save money too ya know.... *hhhmm this conversation has sparked another in me!*
• United States
12 Jun 07
I only have vague memories of this, but I know that we made a solar oven at Girl Scout camp one year. I think it was just a box covered in aluminum foil, though, so I'm not sure how it could have worked. I think you would need to have some black surfaces to absorb more heat, because the aluminum foil would just make it really shiny and reflect the light! :) You'll have to let us know how your experiments this weekend go! :)
@Ravenladyj (22936)
• United States
12 Jun 07
Oh I definately will fill you all in...from what I'm gathering the outside needs to be painted a flat black (with a "nontoxic when dry" paint) and its the inside that is covered in the foil...I'm actually really excited about it LOL
@1grnthmb (2063)
• United States
12 Jun 07
I made and used a solar oven when I was in boy scouts 50 years ago. If you have all day it really does work. Last year my daughter was involved in what was called the solar olympics here in town. The kids spent three months making small cars that ran on solar panels, a model house that used solar energy and a solar oven. It was the exact same design that I used fifty years ago. Let me tell you that the results are the same as using a slow cooker. And it takes all day for you to use it. And on top of that you have to go out and turn the thing every couple of hours so it gets the best sunlight. They do sell such ovens that will track the sun for you but I can imagine that they would be very expensive. But if you want to conserve energy and not heat up your house in the heat of the summer it is definitely a good option.
@Ravenladyj (22936)
• United States
12 Jun 07
OMG thats fabulous!! I'm dying to try it..I actually called my husband at work and cleverly asked him "loverrrrrr...will you make me something this weekend...it won't cost much and it'll save money!" LOL He said yes (AFTER I sent him the link about it LOL).. That Solar Olympics must have been so much fun!! I'd love to have my kids in something like that here...What a great idea!
• United States
16 Jun 07
Oh that's very interesting! That does sound like a really great idea. I had never heard of that before either!! You must let us know how it's done and how it works out for you :)
• United States
16 Jun 07
I've heard of it before and it's quite an interesting concept, I mean it saves energy, time and money, simply by cooking outside, not to mention it keeps the house cool. I think it'd definitely be something to look into.
• India
13 Jun 07
thank you for your information.
• China
13 Jun 07
WELL ,it is interesting .I had herad of the solar engery .and we are using solar shower ,it is very useful .As for the cooking ,it will be hel[ful too. It is good idea ,and it must be advocated to the public .Nature grant us the best gift ,we should take good use of it .Solar energy will reduce enviromental pollution ,and more use of energy ,more clean world we will live in .
• India
13 Jun 07
Till date i haven't seen a solar cooker. I have just heard about it.At times i do solar drying of tomatoes or brinjal, but i don't have any idea of cooking food, in the sun. It will control the pollution but at the same time it cannot be used at night for cooking food.
• India
13 Jun 07
solar cookers will be a great remedy for pollution
@xParanoiax (6997)
• United States
12 Jun 07
I used to do it alot when I was younger..we made our own solar ovens outta cardboard and foil. Bread..you need to get a certain temperature..and you'd need a special design solar oven I think..but I used to make, grilled cheese, eggs, pizza, hot dogs..it's mostly basic stuff you can cook in it, but hey, food's food, right?
@Galena (9120)
12 Jun 07
interesting idea. I supppose it's a bit like sun dried tomatoes. hehe.
@juls146 (966)
• India
12 Jun 07
FAQ's ============================================================= Who made the first solar cooker? The first solar cooker we know of was invented by Horace de Saussure, a Swiss naturalist experimenting as early as 1767. Where are solar ovens being used the most? There are reliable reports that there are over 100,000 cookers in use in both India and China. We are aware of solar cooking projects in most of the countries of the world. See our country by country resources page for information on the use of solar cookers in each country. How hot do solar ovens get? Place an oven thermometer in the sunny part of the oven to get a reading similar to what the cooking pot is "feeling". The temperature reached by box cookers and panel cookers depends primarily on the number and size of the reflectors used. A single-reflector box cooker usually tops out at around 150° C (300° F) as the food approaches being done. High temperatures, however, are not needed for cooking. Your oven will cook just fine as long as it gets up to about 90° C (200° F) or so. Higher temperatures cook larger quantities, cook faster, and allow for cooking on marginal days; However, many people prefer to cook at lower temperatures, since then they can leave the food to cook while they go about their business. With a single-reflector box cooker, once the food is cooked, it just stays warm and doesn't scorch. It's good to keep in mind that food containing moisture cannot go much above 100° C (212° F), unless a pressurized cooking vessel is used. The high temperatures you see in cookbooks for conventional ovens are just for convenience and for special effects such as quick browning. How long does it take to cook a meal? As a rule of thumb, you can figure that food in a single-reflector box cooker will take about twice as long as in a conventional oven. However, when the time required to obtain fuelwood and tend the fire are considered, solar ovens usually demand less of the cook’s time. Also, since you food very seldom burns in a box cooker or panel cooker, you don't have to watch the cooker or stir any food as it cooks. You can just put in a few pots with different foods and then come back later in the day and in general the food in each pot will be cooked and kept warm until you take it out. Of course fresh vegetables will definitely overcook and become very soft if left in the cooker too long. Panel cookers cook smaller portions, usually only in a single pot, but often they cook slightly faster. Some people have reported the need to stir food every once in a while when using this kind of cooker to assure that the food heats evenly. Cooking with a parabolic cooker is very similar to cooking on one burner of a conventional stove. Since the concentrated sunlight shines directly on the bottom of a pot, the pot heats up and cooks very quickly. The food will burn though. So you have to stir it and watch it carefully. Do you have to turn the cooker to follow the sun? Box cookers with one back reflector don't need to be turned unless you are cooking beans which take up to 5 hours. Panel cookers need to be turned more often than box cookers, since they have side reflectors that can shade the pot. Parabolic cookers are the most difficult to keep in focus. These need to be turned every 10 to 30 minutes, depending on the focal length. How do I cook in a season when the sun is very low in the sky? Make sure you are using a light-weight, dark-colored pot not much bigger than the food to be cooked. It also must have a dark lid. The cooker shouldn’t be much deeper than the pot is high. You’ll need to prop the back of the cooker up to lean it toward the sun and adjust the reflector very carefully so that you can see that light illuminating the inside of the cooker. If there is wind, put the cooker in a sheltered location. Should I take the time to build a box cooker out of "real" materials like plywood and glass or is cardboard good enough? Unless you need a cooker that can stay outside even in the rain, you'll do just fine with a cardboard cooker. Cardboard is much easier to work with and holds heat just as well. Some people we know have used the same cardboard box cooker for over 10 years. You can also make the cardboard cooker more durable by painting it on the outside. Would a mirror make a better reflector? While mirrors are more reflective than simpler materials such as aluminum foil, the added gain is probably not worth the increased cost and fragility involved with using a mirror. Also remember that the light bouncing off of a mirror has to go though the mirror's glass sheet twice, each time losing strength. Does it help to paint the walls black? Some people prefer to paint the walls black thinking that the oven will get hotter. It seems, however, that the walls will get hotter, but the food won't necessarily get hotter. We prefer to cover the inner walls with aluminum foil to keep the light bouncing until it hits either the dark pot or the dark bottom tray. Since the bottom tray is in contact with the pot, the heat the tray collects will move into the pot easily. What type of paint should I use? In developed countries you can buy flat-black spray paint that says "non-toxic when dry" on the label. Otherwise, black tempera paint works, but you have to be careful not to wash it off when you wash the pot. Solar cookers in Uganda report that they use aluminum pots that have been blackened on the outside by fire. Is glass better than plastic for the window? People generally report that glass provides about 10% better performance than plastic. And there is reason to believe that under windy conditions, glass is preferred since it doesn't flap in the wind and dissipate heat from the cooker. Plastic, however, is often recommended since it is much less fragile and easier to transport and works plenty well. One excellent, easily-obtained plastic film is oven cooking bags. These are for sale in grocery stores and cost less than US$1 per bag. Other plastics will also work. Plexiglas also works well. What kind of pots work best? Ideally, you want to use a dark, light-weight, shallow pot that is slightly larger than the food you will cook in it. Metal pans seem to cook best. Hardware stores in the US usually carry dark, speckled, metal pans called Graniteware. Shiny aluminum pots--so common in developing countries--can be painted black or can be blackened in a fire. Cast iron pots will work, but extra solar energy is used to heat up the pot as well as the food, so they will not work in marginal conditions. See also Cooking pots What is the best insulation to use? If you wish, you can insulate the walls of a box cooker with various substances. Fiberglass or Styrofoam is usually not recommended since they give off foul-smelling gases as they heat up. Natural substances such as cotton, wool, feathers, or even crumpled newspapers work well. Many people, however, leave the walls empty of any stuffing, preferring instead to place a piece of foiled cardboard inside each wall to divide the space there into two compartments. This greatly improves the insulating power of the walls without the added weight of some other insulating substance that you might use to fill the air space. Most of the heat loss in a box cooker is through the glass or plastic, not through the walls. This is why a few percentage points of efficiency here or there in the walls doesn't effect the overall temperature and cooking power that much. See also Insulation Could I use high-tech materials to make a more efficient solar cooker? You may find that creating a high-performance cooker using fancy materials will make solar cooking more attractive to people in developed countries. In these countries, cooking only makes up a small percentage of daily energy use, but this is because people in developed countries consume enormous amounts of energy for other purposes (driving, lighting, air conditioning, etc.). Introducing these people to solar cooking is a good way to show them that they can integrate alternative energy into their lives. Solar cooking and drying clothes outside on a line are the simplest, least expensive ways to use solar energy to offset some of this high energy consumption. This will hopefully open them to the possibility of using alternative energy in other ways. Millions of poor people around the world, however, still cook over a smoky fire everyday. To find wood for the fire, they have to walk many hours everyday. Other poor city dwellers don't have access to wood, so they have to spend up to half of their income on cooking fuel. These people could never afford an oven made of high-tech materials. So it's up to you to decide which population you want to serve. You could work on creating the most practical solar cooker for people in developed countries to help lead them into a greener future, or you can investigate how to make cookers out of cheap, locally-available materials for people in poor countries who can't afford more. Can you sterilize water in a solar oven? Yes. In all three types, water can be brought to a boil. A little-known fact, however, is that to make water safe to drink, it only has to be pasteurized, not sterilized. Pasteurization takes place at 65° C (150° F) in only 20 minutes. This treatment kills all germs that cause disease in humans, but doesn't waste the energy needed to bring the water to a boil. One reason that people are told to boil their water is that thermometers are not readily available in many places and the boiling action serves as the temperature indicator.