Forgot Password?
Home arrow GreeniacsGuides arrow Solar arrow How to Build a Solar Oven
Written by Miranda Huey   
Share |
Friday, 31 October 2008

How to Build a Solar Oven

If you like the idea of a cob oven, but aren't willing to make such a large commitment to natural cooking, solar ovens are the way to go! Building a solar oven is a simple and cheap way to help save the environment. While many people like to use solar cookers on the road when they don't have access to electricity, you can actually use the free power of sunshine right at home to cook your favorite meals. Like cob ovens, solar ovens have benefits for the environment, your health, and your wallet. If you are interested in finding out how to build a cob oven, check out the Greeniacs Guide: How to Build a Cob Oven, and for more information about solar ovens and how they are used, check out the Greeniacs Article: Solar Cooking Getting Started.

BENEFITS for the environment: Solar cooking helps reduce your energy consumption, not only on energy spent directly on cooking, but also the energy you may need to expend trying to cool down a room that has just been heated up by a hot oven.1

BENEFITS for your wallet: Solar cooking helps you save on your energy bills. If you use it to replace your regular oven, it can also help you save on the cost of buying and maintaining this major appliance.

BENEFITS for you: Solar cooking keeps more of the flavor, moisture, and nutrients in the food.Plus, because you can just set it and forget it without worrying about burning the food, it can save you time, energy, and stress!

Cost: Low

This solar cooker can basically be made from old cardboard boxes and some aluminum foil, materials that are extremely cheap and easy to find.

Time and effort: Low

Building your solar cooker should only take an hour or two. Cooking using the solar cooker is fairly similar to cooking with a regular oven, just double the time.2 The only thing you have to remember is to face the oven directly towards the sun so that it reflects the light back into the oven.3 You will need to have a source of sunlight however, so for those of you living in cities it may be more difficult to set up the location of your solar oven. Temperature does not matter luckily, you just need the sun!

Cob ovens vs. Solar ovens:
BENEFITS
COB OVEN
SOLAR OVEN
Environmental Impact Good: The cob oven is made out of natural and environmentally friendly materials, but one has to be careful to use only sustainable firewood.4 Good: The solar oven is made out of relatively few materials, which leaves little to no impact on the earth. Plus, it gets most of its energy from a very renewable resource, the sun.5
Effort to build
Very High: It is much more difficult to build a cob oven, since it will take a lot of work finding, transporting, mixing, and constructing the materials needed to build the cob oven, in addition to a large amount of time.6 		Low: One person can build a solar oven in just a few hours,7 as opposed to the days or weeks that it could take an entire group to build a cob oven.8
Cost to build Low to High: You can sometimes find the materials for it from the land around you. However, if you can't find the proper material, you'll have to order some in bulk, which could get expensive.9 Low to High: Because solar ovens can be made of such cheap materials as cardboard and foil, they can be very low-cost.10 On the other hand, some high-quality, large capacity, pre-made solar ovens cost a couple hundred dollars.
Capacity Large: Generally, cob ovens tend to be bigger than solar ovens, and therefore tend to be used more with bigger groups.11 Small to Large: Although this solar cooker can only cook one pot at a time, there are some that can cook for up to 12 people at a time.
Lifespan Long: Cob ovens are built to last many years, since they are made of such sturdy material.12 Short: Generally, solar ovens do not tend to last as long as cob ovens, since they are built out of such basic materials as cardboard and foil13, limiting their sturdiness.


How to Build your Solar Oven, based on the “Minimum” Solar Box Cooker14 :

Materials:

1. Two cardboard boxes, one slightly bigger than the other. The smaller one should be about 1 inch taller than the pot you intend to use.
2. Two cardboard sheets. One will be for the base, and the other one for the lid. The sheet for the base should be the same size as the bottom of the smaller box. The sheet for the lid should be a few inches longer all the way around when you put it on top of the bigger box.
3. A box of aluminum foil
4. Newspaper
5. Flat-black spray paint that says “non-toxic when dry”
6. Glue
7. An Oven Bag, especially the turkey sized oven bag
8. Box cutter or knife
9. Hanger wire

Instructions:

1. Close the bigger cardboard box and rest the smaller cardboard box in middle of it. Trace the outline around the smaller box onto the bigger box. Remove the smaller box from the bigger box and cut out the outline you traced, leaving a large rectangular hole on the top of the bigger box.

2. Glue the aluminum foil to all the inner faces of both boxes. Line the bottom of the bigger box with newspaper.

3. Place the smaller box back into the hole. Ideally, the smaller box is about an inch shorter than the bigger box. If not, place the knife in the corners of the smaller box and cut straight down, increasing the length of the flaps. Glue the flaps onto the top of the bigger box. Clip off the parts of the flap overhang the side of the box.

4. Use the cardboard sheet for the base, which should fit into the bottom of the smaller box. If it doesn't, use your box cutter or knife to cut it to match. Glue foil to one side of this sheet, paint the foiled side with the black paint. When it dries, place on the bottom of the inside of the smaller box, black side faced upwards.

5. In order to build the lid, lay the larger sheet of cardboard over the other box base so that the flaps overhang equally all the way around. Make sure that, when you are facing from the direction of where the box should be, the corrugations run left to right.

6. Fold the flap overhangs on each side, leaving 4 creases in the box. When you look at the cardboard sheet, there should be four squares on each of the corners. Cut one of the sides of each one of the “squares” so that when you put the sheet back on the box, the square itself can be folded over to another side of the box, forming a lid. Take the sheet off the box and glue the lid together.

7. In order to build the reflector, draw a rectangle on the top of the box which will be the lid opening. One of the sides should touch the edge of the lid, and this will become a hinge. Cut the other three sides of the rectangle and fold them back. Cover this new flap with aluminum foil on the inside.

8. Turn the lid over. Get out the Reynolds Oven Bag and cut the bag to fit inside the lid. After cutting, glue any remaining opening closed so that all the sides are shut airtight. Then, glue it directly onto the underside of the lid.

9. Get a 12 inch piece of hanger wire to use to prop up your reflector. Bend the top inch of it 90 degrees one way, and bend the bottom inch of it 90 degrees the opposite way. You can rest one side on the reflector and the other side on the lid, keeping the reflector open.

10. Place a big black pot in the middle with the food and start cooking!15

Enjoy your accomplishment along with your flavorful, moist, nutrient-packed meals!

Browse all Greeniacs Guides Browse all Greeniacs Guides        Browse all Greeniacs Articles
_______________________________________________________________________________


1 http://findarticles.com/p/articles/mi_qn4179/is_/ai_n28118213.
2 http://www.allfreecrafts.com/nature/solar-cooker.shtml.
3 http://findarticles.com/p/articles/mi_qn4179/is_/ai_n28118213.
4 http://www.greeniacs.com/GreeniacsGuides/How_to_Build_a_Cob_Oven, hereinafter “Greeniacs Guide: How to Build a Cob Oven”.
5 http://solarcooking.wikia.com/wiki/%22Minimum%22_Solar_Box_Cooker.
6 Greeniacs Guide: How to Build a Cob Oven.
7 http://solarcooking.wikia.com/wiki/%22Minimum%22_Solar_Box_Cooker.
8 Greeniacs Guide: How to Build a Cob Oven.
9 Id.
10 http://solarcooking.wikia.com/wiki/%22Minimum%22_Solar_Box_Cooker .
11 Greeniacs Guide: How to Build a Cob Oven.
12 Greeniacs Guide: How to Build a Cob Oven.
13 http://solarcooking.wikia.com/wiki/%22Minimum%22_Solar_Box_Cooker.
14 Id.
15 http://solarcooking.org/plans/minimum.htm.




Add your comment
RSS comments

Only registered users can write comments.
Please login or register.

Click here to Register.  Click here to login.
Last Updated ( Tuesday, 09 August 2011 )

SEARCH GREENIACS.COM

Green Facts

  • You’ll save two pounds of carbon for every 20 glass bottles that you recycle.

  • Every week about 20 species of plants and animals become extinct.

  • Americans throw away enough aluminum to rebuild our entire commercial fleet of airplanes every 3 months

  • Recycling 100 million cell phones can save enough energy to power 18,500 homes in the U.S. for a year.

  • Rainforests are being cut down at the rate of 100 acres per minute.

  • American workers spend an average of 47 hours per year commuting through rush hour traffic. This adds up to 23 billion gallons of gas wasted in traffic each year.

  • A tree that provides a home with shade from the sun can reduce the energy required to run the air conditioner and save an additional 200 to 2,000 pounds of carbon over its lifetime.

  • An aluminum can that is thrown away instead of recycled will still be a can 500 years from now!

  • Refrigerators built in 1975 used 4 times more energy than current models.

  • Recycling 1 million laptop computers can save the amount of energy used by 3,657 homes in the U.S. over the course of a year.

  • Less than 1% of electricity in the United States is generated from solar power.

  • Americans throw away more than 120 million cell phones each year, which contribute 60,000 tons of waste to landfills annually.

  • A steel mill using recycled scrap reduces related water pollution, air pollution, and mining wastes by about 70%.

  • Shaving 10 miles off of your weekly driving pattern can eliminate about 500 pounds of carbon dioxide emissions a year.

  • For every 38,000 bills consumers pay online instead of by mail, 5,058 pounds of greenhouse gases are avoided and two tons of trees are preserved.

  • Turning off the tap when brushing your teeth can save as much as 10 gallons a day per person.

  • Bamboo absorbs 35% more carbon dioxide than equivalent stands of trees.

  • Americans use 100 million tin and steel cans every day.

  • Glass can be recycled over and over again without ever wearing down.

  • It takes 6,000,000 trees to make 1 year's worth of tissues for the world.

  • If every U.S. household turned the thermostat down by 10 degrees for seven hours each night during the cold months, and seven hours each weekday, it would prevent nearly gas emissions.

  • States with bottle deposit laws have 35-40% less litter by volume.

  • You will save 100 pounds of carbon for each incandescent bulb that you replace with a compact fluorescent bulb (CFL), over the life of the bulb.

  • One recycled aluminum can will save enough energy to run a 100-watt bulb for 20 hours, a computer for 3 hours, or a TV for 2 hours.

  • 77% of people who commute to work by car drive alone.

  • 82 percent of greenhouse gas emissions in the U.S. come from burning fossil fuels.

  • Nudge your thermostat up two degrees in the summer and down two degrees in the winter to prevent 2,000 pounds of carbon dioxide from entering the atmosphere.

  • Due to tiger poaching, habitat destruction, and other human-tiger conflicts, tigers now number around 3,200—a decrease in population by about 70% from 100 years ago.

  • Current sea ice levels are at least 47% lower than they were in 1979.

  • The World Health Organization estimates that 2 million people die prematurely worldwide every year due to air pollution.

  • A laptop consumes five times less electricity than a desktop computer.

  • Plastic bags and other plastic garbage thrown into the ocean kill as many as 1,000,000 sea creatures every year.

  • In California homes, about 10% of energy usage is related to TVs, DVRs, cable and satellite boxes, and DVD players.

  • In the United States, automobiles produce over 20 percent of total carbon emissions. Walk or bike and you'll save one pound of carbon for every mile you travel.

  • Recycling for one year at Stanford University saved the equivalent of 33,913 trees and the need for 636 tons of iron ore, coal, and limestone.

  • Washing your clothes in cold or warm instead of hot water saves 500 pounds of carbon dioxide a year, and drying your clothes on a clothesline six months out of the year would save another 700 pounds.

  • You will save 300 pounds of carbon dioxide for every 10,000 miles you drive if you always keep your car’s tires fully inflated.

  • Recycling aluminum saves 95% of the energy used to make the material from scratch.

  • A single quart of motor oil, if disposed of improperly, can contaminate up to 2,000,000 gallons of fresh water.