Introduction: Solar Food Dehydrator (Dryer)
Dry your fruit, vegetables, and other goods with your own sun powered dehydrator. Electric Food Dehydrators can be expensive and consume unnecessary energy.
This solar dehydrator was made entirely of recovered materials. It was constructed with scrap ply wood, 2x4s from an old ladder, a house window, and other items which could be considered trash. It was created as a project at Maharishi University of Management in Fairfield, Iowa.
Why We Dry: Removal of moisture prevents bacteria from ruining your values fruits and vegetables. Drying is a form of preservation.
Step 1: Learn the Design
Become familiar with the design to minimize mistakes...
There are vents underneath in the front which are hidden in this picture. The darker section is a piece of heat absorbent material, we used painted metal for this particular dehydrator, but other materials will do as long as they are dark. The food itself is placed on the shelf, which will be made out of a cloth screen. Other screen-like materials can be used, but take chemical leeching into consideration to prevent contamination. The back piece of ply wood can be opened to remove the shelf and provide additional ventilation.
Step 2: Find Materials
Thin Ply Wood (Body)
4 2.5' Long 2" x 4"s
10 feet of 2" x 2" wood (Braces and drying shelf support)
A Window (20" x 23 1/8") or a suitable slab of clear plastic.
Screen (For covering vents)
Stretchable Cloth/Material. We used stalkings. (For drying rack)
A Hook & String (To fasten the rear door)
Caulk (For perfectionists)
Step 3: Size Pieces
Here is a checklist for the plywood pieces.
-1' x 23 1/4"' (Top)
- TWO 20" x 12" x 26 1/8" x 14 1/8" (Sides) This has a diagonal cut.
-26 1/8" x 23 1/16" (Bottom) This will be trimmed to fit legs and vents.
-14 1/8" x 23 1/16" (Back) This will be on hinges.
Step 4: Assemble Frame
A. Cut 2" x 4" notches out on the bottom ply wood piece for legs. Cut out 2" x 4" slits for ventilation.
B. Construct base first as pictured.
C. Fasten side pieces of ply wood to legs.
D. Attach rear ply wood piece.
E. Screw 2" x 2" on top of side pieces to anchor the top piece. (This is more clear after viewing the second picture on this step)
*Drill then screw to prevent splitting
Step 5: Additional Components
A. Size and Insert heat absorbent shelf (Approximately 23" x 20") . This rests on the top of the legs.
B. Construct drying screen by stretching and stapling material over a 14" x 22 1/2" frame constructed of 2" x 2" pieces.
C. Cut and attach support piece for drying screen.
D. Attach the window. Caulking the borders is recommended, but if the window is flush against the frame, then caulking is optional.
E. Cover vents with screen material to protect from insects.
F. Place thermometer inside, ideally close to the drying screen rack.
*Clean parts before adding them
Step 6: Dehydration Tips
A. Dehydration will occur between 100 and 140 degrees Fahrenheit. Any lower and bacteria can grow, any higher and it will be cooking. In order to achieve this balance the rear door may need to be left ajar.
B. Different fruits and vegetables have different optimum drying temperature ranges. Research what you are drying to find this out.
C. Remember to store your result in a dry place.
Thank you for reading our directions!