Tuesday, April 14, 2009

Solar Dryer

After 3 days of hard work, 2 calloused fingers, and a few cuts, I've finally finished (almost) our solar dryer. All we need now is the glass to cover the "hot air harvester" - more about this later.

Here it is!!!

From this angle you can see the exhaust at the top and the air intake at the bottom. At the back is the door.

Here's a better view of the air intake. Hot air goes in there.

This is where hot air exits. We'll be installing a fine meshed screen at the vent to avoid insects or other foreign objects from getting in.

I haven't made trays yet, but hanging bunches of leaves/herbs would work just fine.

This is the "hot air harvester" that i was talking about. The black part is made of GI (galvanized iron) metal sheet painted with black. The reason why its black is because black absorbs heat better. A glass sheet will cover the top part of the "hot air harvester" leaving about 4 inches of space in between the metal sheet. The bottom of the harvester will be left open so air can enter. Then the air will be warmed up by the metal sheet. Since hot air rises, it will enter our dryer and pass through whatever we place in there and exits through the vent. Herbs, fruits, meat, fish, are just a few examples.

We'll be posting more pics of our dryer in action soon after the paint cures.

I hope you got the idea on how this solar dryer works. If you have questions, feel free to post it at the comments section below or send us an email.

8 comments:

Anonymous said...

Hi Raymond and Mariel!

can this solar dryer be used to dry malunggay leaves without damaging its nutrients? because they are saying that it should be air-dried only not sun-dried. Thanks po!

Raymond and Mariel......................................... said...

Yes, it can dry any kind of herb and even fruits without loosing its nutrients.

and another

Yes, sun-dried herbs loose their flavor and nutrients.

and another

Yes, they should be air-dried.

The solar drier uses the suns rays to absorb heat through the metal sheet. When the metal sheet heats up, it also heats up the air around it. As stated in the post and according to science, "HOT AIR RISES". So "air" let me type it again "AIR" rises to the opening at the bottom of what looks like a cabinet where your herbs are. The sun's rays cannot penetrate that wooden box. So what we are doing is basically "air-drying" the herbs with warm air to make it dry faster. The air that passes through does not even reach 40 degrees celcius.

I hope this clarifies what the solar dryer really does.

Than you very much for asking. :)

GOwin said...

Raymond, I think you should also point out that this is an INDIRECT solar dryer, as opposed to the Direct solar dryers, which many people often think of.

GOwin said...

Direct solar dryers uses radiant heat, while indirect solar dryers uses the hot heat generated by the trapped air in the solar heater and direct this hot air to a drying chamber.

(Sorry, itchy fingers.)

Raymond and Mariel......................................... said...

Thanks GOwin for helping me on that explanation. Maybe I should post more pictures of this dryer in action. Right now it is on exhibit at the AANI Herbal Garden in Quezon Memorial Circle. I'll be bringing it to the farm soon.

Gilbert said...

Layered wire mesh can be a good tray inside your drying chamber so that air can circulate from inlet going to your chamber outlet. Container tray should be below your drying chamber as a catch basin for dried/powderized product... just a suggestion...:)

Dr.Joe Okeke said...

Dear Raymond and Maria,I salute you in a special solar dryer project.We're happy for we're your partners in Africa West.
Dr.Joe Okeke
Joenewideas International
26 Ziks Avenue
Awka-Nigria
234-08064305190

Anonymous said...

Dear Raymond and Maria,I salute you in a special solar dryer project.We're happy for we're your partners in Africa West.
Dr.Joe Okeke
Joenewideas International
26 Ziks Avenue
Awka-Nigria
234-08064305190