Hi derrick: check out my post under
food preservation in the forums. I give my plans for a
solar food
dryer that will dry herbs in a half a day. You can build it any size, from a hand held unit that could sit in an apartment window, to way larger than the 2'x8' one that I show. As far as using a
rmh to dry herbs, any heat sourse will work, protect from lite & dust & allow air flow . Good luck Tom