Any sort of sustainable food plan that involves a garden and/or fruit trees needs a good dehydrator. This in conjunction with some canning and some animal protein can get you through any low production season.
Here is a solar dehydrator that uses a solar heat collector and dc powered fans to push hot air through the dehydration chamber. I built without plans and based the size of the solar collector on how the beer cans would fit in when stacked up. The fans aren’t needed, but can improve the air flow. They use so little wattage; they can run off of a small 10-15w solar panel. Or you can plug them in.
Step 1: Sizing the Solar Collector
Gather some aluminum cans of your choice, measure the boards based on the sizing of the cans and the number of rows you’d like. My box was 117cm x 69cm. I used a variety of different can sizes. I also used a treated lumber since this will be sitting outside all of the time. I used 2×4’s for the entire construction.
Step 2: Build the Frame
Based on the size of your collector, build the dehydration chamber frame so that the collector can lean up against it as seen in the finished picture and be mounted on the inside of the frame.
Step 3: Roof Supports and Solar Collector Mounting
Step 4: Solar Collector Bottom and Air Vents
Next you’ll need to make a bottom. I used DensGlas, an outdoor rated gypsum board. Then you’ll need to add your vents. You want air to move freely so don’t put vents where there are going to be cans in the way. If you use fans, you’ll want to cut holes based on the shape of fan you use.
I used “CoolerGuys” dual blower computer cooling fans from Amazon. They’re variable speed and built to be used in a hot environment so I thought they would be good for this application.
Step 5: Trays and Side Support Crossbeams
Add your tray guides and side support beams. These trays can use whatever you heart desires: screen, mesh, grating…wood slats. Get creative.
Step 6: Filling the Solar Collector
I took a piece of corrugated roofing, cut it to size and painted it black and put it in the solar collector. Then I painted all the cans black and began stacking them. Be sure you do not block air holes.
Step 7: Electric Fan Installation
Step 8: Complete the Solar Collector and Attach the Roof
Place a piece of Plexiglas or regular Glass over the chamber. Then screw on the roof. I used an extra piece of metal roofing we had laying around. I didn’t put a smoke stack on the roof. The roof gap allows good air flow. Be sure when you finish to use screen on the gaps between the roof and the wood for bug protection..
Double check your construction. Now you’re ready to put on the walls and door!
Step 9: Finished
Here is the finished solar dehydrator. I used Densglas sheathing for the walls. It’s staying outside, so I’m glad that I overbuilt this a bit. It’s larger than most because I wanted the option to dry massive amount of herbs and teas all at once. In addition we grow lots of stevia.
We’ll see how full I can fill it when making jerky and other more high moisture content foods.