Woodgas from woodchips

Has anyone had success with wood gas from wood chips? Texas A&M claims the local juniper has the same BTU content as bituminous coal. This wood is considered a trash tree and is widely shredded.



A few have, yes.

But the chips have to be the right shape and size, and dried well.


technically sub-bituminous coal which is similar to the wyoming white powder basin coal. More energy content then Lignite but less then bituminous coal.
Mesquite is similar to Juniper.

Osage Orange is slighly better. I was all over it! It is related to the mulberry, it is used for long lasting fence posts, wood for bows, used for woodworking, hard as iron, live fences to keep cattle in, the highest btu, produces latex, possibly an insect repellent, etc. Then I got to the part about the thorns… :slight_smile:

Here is a research paper on their method for the juniper and mesquite.


They need to be very dry, clean, sized correctly and are application dependant. Consumption rate verses gravity verses the size of the gasifier.

Too small of a hearth the fuel wont flow, too large the fuel density charge will be too greate for the machine to process.


Well Tone with his gasifier design disprooves all those woodchip theories. Look at what he burns in his tractor, anything from dust to chunks. I have had one of his machines on my tractor and frankly, if some welds wuldnt fail, l probably wuldnt swich it back. He seems to have got things right. The cilindrical design prevents bridging and the low nozzle prevents constipation. Those two things are preety much the only problem with woodchips.


Chips are all I run mang. I built that Farm All M it was a chip machine and it ran great. Not so grate on the small engines though with all the flow issues. I think there is a sweet spot for chips and the I4 and I6 engine I think are that sweet spot.


Then there was this baby, we put at least 200 hours on it after got it proofed out. It never skipped a beat on our fuel. Shipped to Italy and they put chips from Olive branches that were smaller and no good. We had to use chips on these as they wanted large hoppers systems. To keep from overwhelming the hopper with moisture we build the auger feed systems to keep the hopper charge to a minium.


Wood chips and lots of small branches is another reason I am going to try the lower nozzles in my gasifiers that I’m building. Both WK Gasifier in design. I have always had all this extra charcoal in my clean out of the lower gasifier. If I can turn it into extra rich gases, it is a win ,win as far as I can see. And then less clean out.


I may have posted this sometime ago, but here is my webpage on woodchip measurement::

Pete Stanaitis


Thanks all for responses.

Yes, the local juniper has heat equivalent to sub-bituminous coal.

This time of the year shredded Christmas trees are avaliable. I can load almost an unlimited volume of woodchips because open burning of woody rubbish is usually restricted by the county because of wildfire risk.

I will attempt to contact Texas A&M University as they have published woodchip documents on the internet. I don’t want to sort the material by size. I may mix in shredded paper and cardboard.

I’d like to use wood gas to power a 4 kwh generator and also capture the heat - maybe warm a small greenhouse.



You’re going to want to go a lot bigger than that. My experience the V twins are as small as you can really go that will be reliable and allow for a large enough gasifier that can flow. Start golng smaller than the flows are more dificult to achieve. Also remember what ever that gasoine rating is you need to cut in half that is now the max continouse output. Then you have reduce even more to allow for fluxuation as now you are running a solid fuel. It will constantly fluxuate.

If you can figure out a way to make charcoal without creating a fire hazzard you might want to try that. This will allow a smaller engine and a charcoal gasifeir is far less complex and much lower cost to produce.


Shredded wood is different then wood chips.

Wood chips need to be sorted, and shredded doesn’t usually work.

If you have shredded, you might try compacting it. There is resin in the juniper and pine, and it -might- stick together with enough pressure to create heat to make disks or pseudo logs without a binder. I don’t think anyone here has tried pine or derivatives.

This stove is the same basic principle, but I am guessing even he sorted first.


Hi TimK. welcome to the DOW.

The single most important factor of sussess wood gassing is WHY they are pursing it.
Finally you answer that in the last line of post #9.

So first just ignore all of the piles and piles of “free” other people made chipped-up and shredded woody debris. Those were the results of just getting rid of problems in the most economical way.
Distractions no different then standing at the oceans edge think all of that water could be improved and put to some use. Yeah. Learn to surf fish.
A distraction no different that going up in the high mountains for the first time and goggling all of the white pure snow thinking if I could only deliver this down into one of the big Cities. Ha! Already happening in half-year slow meltoffs used of foods making irrigations.

Next do realize that BTU’s values of any fuels is pretty much meaningless so far as making good continue use IC engine shaft power. The Natzi German war machine with lower power capable aircraft fuel kept kicking Allied ass by making their engines 50% larger in displacements. And their manufactured fuels proved to be much cleaner burning with less engine internal gunks building up than the higher octane, better Allied fuels. Needing less downtime mainteneces.

Third realize with the growth of free-easy Web-Internet presentations 99% of what you can search up find and see; or have presented to you as “proofs” arborist all ground up mixed leaf-needles, whisker ends, branches can be easy woodgaasses to fuel small IC engine generators are carefully clipped, snipped 2-5 minutes presentations. Lies. By, damn liers.

IF your specifically pre-clean branches and growth leaders; and specific machine large chip for engine grade fuel . . . those wood chips can be small engine gasifier fuels. Stephen Abaddesa shows this well. Greg Manning has too. Even the Swede fellow JonasH. (Tip: harvest as winter saps-down woods.)
Or . . . sort classify mixed like PeteS. shows best well. BenP. has shown in his books.

As very expreinced having tried all ways for years Matt Ryder has said: if you truly want and need 4KW electrical then set aside, sell what you do have now, and go at least 2X bigger as a base system to then try and work around. And for best simpilest systems results have that be at least a two cylinder IC engine. Three or more cylinders, much better. And be at least 500cc and larger. Example being Dean Lasko’s first attempt - Works! system he recently YouTube showed. Using mighty low BTU wood stocks I might add.
So DO make your own purpose made wood fuel stocks. For controlled best results.

Do not ever drift off allowing yourself to be another’s disposal problem solver.
Ignore numbers slinging talking heads geeks.
Steve unruh