Allen Jangula

Everything I researched so far points to the Rocket stove being very efficient.

First I'll have to get a Batch rocket stove set up.
Then work on a secondary barrel with heat pipes.
Being for shop, not to concerned about mass.  Just want efficient instant heat without having to burn a whole forest.


I do have some spare VFD's and 3 phase 1/2 HP motors ( I have some odd hobbies)
Should have a Raspberry PI sitting around too.
To play with fan speed and flue temp.

That stuff has all doubled in price is 2022.
Electronic are almost impossible to get.  Order some wifi stuff 8 months ago and still in back order.
May have to switch brands and models.

I find it easier to research and ask question, plan for future expansion before start cutting and welding.

thomas rubino wrote:Good Morning Neighbor;
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Now on to your questions.
I'll start by giving you my opinion of your final question.
No, not worth the money to set up that kind of testing.
If you had all the equipment on hand, it would be fun to see what numbers you came up with.
Buying that equipment is very cost prohibitive.
The innovators have done extensive testing and fine-tuned their designs to run as cleanly and efficiently as possible while storing that heat in a mass.

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Hi,   Been doing a lot of research about Rocket Stoves to heat a large shop.  Please bear with me.

Seems to me the difference between a Rocket stove and Rocket Mass is Rocket for instant heat and Mass is for longer heat release?

catalytic converter:  appears a rocket stove is just a modified wood stove with a massive catalytic converter that, in theory, will not plug or burn out?
Wood Stove catalytic converter will melt down if fired over 500F  where as fire brick will take about 2000 to 3000F.

Rocket stove vs wood:
Wood stove dissipate heat directly from the wood fire where as a Rocket stove  dissipates heat after fire / smoke has gone thru the heat riser (catalytic converter)?  
Heat dissipates off the 55 gallon drum.  I don't like that description, sounds cheap, Going to call it the Primary Heat Exchanger.
Primary heat exchanger can be made from lot of things, 55 gallon drum, air tank, fuel tank, etc. Just has to be metal?

From what I read, the top of Primary heat exchanger should be about 2" above the Heat Riser.  Seems like a thin barrel that close to the heat riser would burn thru?  Basically the sheet metal is getting hit with about +1000F steam of air.
Should a person mount a fire brick to the top inside of the Primary Heat Exchanger to take the brunt of the heat to spread out the the hot gases?

Flue gas should be about 110F to 140F  seems to be general consensus.
How do you control that?  Seems only way to control flue temperature would be to control how  much wood you feed at a time?

Also found something called a Batch Rocket Stove.
Which is what I'm leaning towards.
To me is a modified wood stove using the catalytic converter properties of the heat riser and Primary Heat Exchanger

Granted this takes away from the basic simple non power rocket stove but.....
lets just say you are building the Batch Rocket Stove for maximum heat recover, minimum wood usage. ( which would be my case)
Inflation driving cost of everything thru roof.   NW Montana cord of fir/ lodge pole is running $275 to $300 a cord. Well, they call a pickup load a cord.  Too old to cut my own.

Add a Secondary heat exchanger that has heat pipes running thru it.
Add a variable frequency drive fan blowing air thru the Secondary heat exchanger to maintain about 125F flue temperature.
Install a type K probe into flue.
Would need a Raspberry PI to control VFD.
Would greatly increase the complexity but you could maintain max heat recovery.
Being you have a Raspberry PI, might as well put a type K temperature probe in the heat riser ( inside a heat brick) Use that to control damper for secondary air to riser. Maintain a set temperature in fire brick
Could also control primary air damper to control main burn/ gassification of wood.
Being a Batch Rocket Stove, you could load it up and would burn overnight or at least an extended period of time with no one there.
Monitor and add some safety control.   text you if something goes out of wack.  Some basic HMI to your phone over wifi

The Rocket stove just needed some Rocket Science... Ar ar ar

$64,000 question.  Would it be worth it?
Cost at least $1000 to add the PI and VFD

Thoughts?