Bruce, good ideas but remember that co2 is not all it will make. It will also make CO and thereby, if you’re not careful, a dead yankee transplant.
Same warning for you Kristijan, long flat or slanted chimmeneys can drop CO back into your heated air space… Especially, as Steve U says, while cooling off… be careful.
Hey, just realized I was responding to a pretty old post. I guess you guys didn’t need me after all. You’re still alive…go figure. haha 
CO detectors are fairly inexpensive. Well-tuned TLUDs are pretty good at consuming the CO. I’m partial toward fan assisted control. Some even burn with a blue (CO) flame. I’ve heard that there is another problem with the high CO2 environment, but I can’t quite remember what it is. Maybe good foliage, but poor fruit or something like that? Maybe it is about being in the right range? Maybe something in the download available here: Download Vaisala's greenhouse CO2 measurements document
Yours truly, a verdant yankee transplant
Yeah, I know, preaching to the choir here.
Weather is much too hot for most outside work these days, but its cool and comfy in the cellar so l digg out a couple of buckets every day. I was wondering, since this sandstone bedrock is old ocean floor, there shuld be some fosils? I was looking for shells and snails and stuff like that but nothing showed up. I thod this sea was dead untill l realised fosils were there all along, l just didnt bother them!
Those marks were there all the way, it is only recently l noticed the vains in the middle, no dubt they are milions of years old leafs.
This, l have no clue what it is. The bedrock is full of them.
They are like sort of eggs, wery hard rusty shell and Nutella consistency greesy clay inside. Any idea what this is?
Snails fossils maybe?
S.U.
Winter is seting in, time to fix the greenhouse heater. This is what l came up with.
Hi Kristijan, I like it. The adjustable pipe on top should work as a afterburner to burn up the gases that are created. The three pipes being at different levels could be creating a draft above the charcoal below and keeping it activated. But as the char bed gets deeper and fills up to the grate it should go out. Putting some insulation on the lower hatch door will seal it off from any small air leaks getting in through there.
Keep us posted on this new green house stove heater, that also makes charcoal fuel. Thank you for the video and your plants look great.
Bob
I think I understand the bridging issue, as there’s no movement to shake char down. I would use a sliding grate on top of the existing grate to disrupt the char bed, maintain a downward flow, and move or break obstructions.
The old kitchen wood stoves had cast iron teeth grates a bit like a paper shredder, but I think they were just meant to drop the coals.
Thanks Bob,
Thats exactly the idea (the afterburner).
I hope the skech is helpfull. You can see the angle iron grate. Its wery loose, about 4" spaced. The idea is as soon as the wood chars in the flame, the char flakes and falls in the bin.
Hi Gary,
This is most likely the case. I took the house boiler as a example, after you load it and the wood is burned, all thats left is a nice pile of charcoal, eaven sized for a gasifier. This is what l tryed to reconstruct.
I was thinking about a moveing “scraper” but decided to try without it first. Looks like it will be nesseseey.
Allso there is a problem with air inlets, they act too much like nozzles. Too turbolent enviroment in there so a lot of charcoal burns on the log before it can flake off. The idea was to have a flame around the log that blocks the air.
Oh, Gary, you saw your tomatoes taking over the greenhouse? 
I did see the tomatoes, recognized them right away, that’s hilarious. Just imagine what they will do in the wild, as the birds and kids carry seeds here and there.
As for the nozzles, I wonder if something below grate level might work better? Or even partial combustion air from below grate? Or just some sort of diffuser, maybe more like your charcoal nozzle?
Im not complaining l have no problems picking tomatoes beside blueberrys and raspberrys in the woods 
That was the original plan, l already had a air inlet under the grate but thod that wuld burn my charcoal in the bin and went the rout l am now. But the fact is when l open the char emptying lid and air is drawn trugh the grate, it seems to burn better/cleaner. But how to prevent char being burnt?
I think the breaking down of coals in a stove is largely due to combustion anyways, so it’s probably no loss. Same process in a downdraft gasifier, char is “burnt” through reduction.
I suppose if residence time was increased at pyrolysis temperatures charcoal yield would increase, but it probably still needs mechanical breaking and agitation.
I consider it a good result if you are producing heat and collecting charcoal, the yield in a way is a free bonus.
As those Spoon tomatoes spread perhaps the neighbours will name them after you. It sounds like they are there forever, soon all the children will be foraging… 
Agree. The main objective is greenhouse warmth. But if l can allso drive with a byproduct, thats eaven better
Naahh that wuldnt work. Naming the wild growing tomatoes Garryberrys is far better
Hi Kristijan,
Clever heater/charcoal maker. I’m sure with a little finetuning you will be able to maximise your yield. With a similar house boiler setup as well, you could be self-sufficient on char for transportation.
I think I would re-design for downdraft, and post grate complete combustion, same concept as a typical gasifier, seems to be the most efficient form. Slip the char for later use.
when you value all the by-products of wood burning (greenhouse heating, charcoal production …) the yield is always 100%.
it is the proportion between the two products that changes
great idea, Kristijan, I’ll try to copy you to heat my greenhouse:wink:
I think
if the post-combustion hot gases could overheat the charcoal under the grate (as in
an oven) before joining the chimney the pyrolise would be improved 
Turns out all 3 of you guys were right
Indeed, the kiln neaded fine tooneing. A couple of problems occured. The choo-choo pulsating effect got stronger and stronger as things heated up. To a point it started spiting fire/smoke out the air inlet, not good. But then l accidently left the hopper lid open a couple of mm and the pulsation stoped. The whole thing started to work like a downdraft boiler. The air inlets worked like secundairy airlets burning the gas. In a couple of hour the whole hopper turned to char and the whole hopper was glowing dull red. Loading the next batch of logs in chrushed the char, made it fall in the char bin. Since the hopper is already red hot the wood starts burning instantly and the cycle begins. I filled half a 55gal drum with char in no time! Unfortunaly l had to stop the cycle becouse l feared the growbed becomeing too hot and hadnt lit it for 4 or 5 days. When the real cold starts l will be able to make lots of char.
