Hi Lori,

I look into these things but as of yet not built any. See the links for helpful info.

http://www.chelseagreen.com/content/weekend-project-how-to-build-your-own-cheap-simple-solar-oven/

http://www.motherearthnews.com/real-food/solar-food-dehydrators-dryers-cookers-zl0z0807zalt.aspx#axzz2gqz3Z0aL

Mark

I think a solar dehydrator should be similar to a solar water heater panel but maybe deeper. The greenhouse effect will trap solar heat in, raising the temperatur.

But the complication arises that in dehydrator you have to replace the air in order to get the moisture out.

How you'd do it ? I think you have to have a DOUBLE chamber construction.
You separate the chamber (where you have the veggie ) inside the main chamber by clear material(plexi, glass). You only circulate the air in that chamber. The main chamber has a sealed construction. This means you never open it.

I was just curious if anyone had personally experienced the results.
I have been studying various models of dehydrators and the actual construction is a no brainer. Yes, it needs a solar collector which really only uses the hot air to create natural convection/dry moving air. Can't decide if I need to build the veggie chamber with a chimney type draw or a sink and updraft. Cannot be totally sealed, air has to move through both so an inlet and outlet are necessary.

Just as a note and hair raiser - one of the engineering classes at a university made one - get this - using pressure treat- how'd you like those chemicals in your nice little peppers!!

I may look at dual purposing my water heater to be the solar collector and just build a food chamber/drying module.

Lori

Hi Lori.

I don't know if you're familiar with Cindy Conner, but I believe she has done what you're wanting to do. Check out her blog at the link below. You can probably contact her for more advice; she's a very nice person! Her first book is due out in the Spring, 2014 and many folks say "it's about time!".

Good luck!

Rick

http://homeplaceearth.wordpress.com/2011/05/31/solar-food-dryers/

Here is a link that might be useful: Cindy Conner - Solar Dryer

Thank you so much for the link. I read her blog and am really impressed. I've decided that I'm going to try using something already manufactured like a cart for the drying unit and attach the solar collector to it. Just got to think this through. My solar water heater is raising a trough of 12 gallons of water almost 30 F at this time of year so the sun is still working for me.
Thanks again - this really encourages me.
Lori

I looked into Cindy Conner dehydrator. It is just a shallow slanted box with a glass top on 4 legs With a simple vent holes. It might work tho. Sun drying is taken a step forward.

Yes, I think that I will use screening within the cart to capture more solar heat than what she has plus I will have a small solar powered fan inside to enhance the air flow beyond just the draw.
I plan on making it this afternoon - a gloomy rainy day today and will be ready to test in tomorrow's sunshine..

CanadianLori ... That would be something. You would want to dry your veggie(or whatever) with heat not by sun rays. If you don't draw enough air it will steam up. If you draw too much air, won't build up temperature. . So you want to vent the veggies compartment not the main solar compartment.
The drying compartment should have black or flat grey color facing the sun made of a conductive material like aluminum plate.

Here's how it came out - of course there is no sun to test the temps...
This is the front view. Sitting in the top is a little computer fan and the mini solar panels. The side facing the sun has the dark screening across the entire surface inside the plastic. Plastic is 40gauge uv blocking and tinted because that's what I had on hand. The "shelves" are wires with screening glued to them that simply fit into the holes on little corner braces along the inside of the side rails.