Glenn Herbert wrote:The trouble with harvesting more heat from the stovepipe of a regular woodstove is that you risk making the exhaust cool enough that creosote condenses in the chimney and may cause chimney fires. A rocket mass heater (and to some extent a rocket stove) burns every bit of creosote to make heat, before harvesting the heat for the house; thus there is no creosote to condense and be hazardous.
I have ZERO problems with creosote in my EPA rated woodstove. The trick? Kiln Dried
firewood produces no creosote, no fungus, no mold, and even less smoke. The benefits, a better heat overall. The other bonus is, it's not at all expensive,
that is IF you build your own kiln box dryer. Oh boy, another project folks!
No, I don't want to earn apples or badges or whatever here and undertake another project, instead check out this link ...
Here's a great example to build your own.
https://www.wagnermeters.com/kiln-drying/solar-dried-lumber-moisture-concerns
A kiln box dryer is just another version of a
solar food dehydrator. Takes a little less effort to build since it's just a box with wired racks full of split wood. Think of it as a sauna for a cord of wood.
Many of the farm stores and coop stores
sell campfire bundles now wrapped in plastic that have been thru a kilin dyer process.
About kiln dried firewood wood
Kiln-dried firewood delivers a higher BTU, does not produce the potentially harmful creosote buildup in chimneys and leaves little
ash. The treated wood is bug-free and contains no fungus, a relief to individuals who may suffer from allergies. The kiln-dried wood destroys the breeding ground of the Asian Longhorned Beetle and Emerald Ash Borer, a troublesome infestation of Northern forests. Kiln-dried wood allows campers and others to transport the wood across state lines without fear of infesting the forests.
Kiln-dried firewood has ± 15% moisture compared to ± 35% moisture in seasoned firewood. Unseasoned (green) firewood can contain 50% or more moisture.