Wood IS THE Freedom Fuel!

Maybe I have the insight?
Miscanthus fuel sounds similar to the Paulownia quick grow WayneK tryed in the past.
He said it worked. But was lightweight requiring many refuelings fills for him.
Fast grow woods do have high silica ash percentages.

KoenV.L. used much bamboo successfully.

Both of them “slip” out intentionally a lot of char/ash to keep their systems flowing. That slipped-out char later recovered. Re-used.
The majority of the silica is still in the slipped char particles. Not free to melt.

My current 480 pound wood stove leaves no remaining char. The stoves heat driving mass causing all of the char to burn consume. Great for efficiency wood-to-heat watts.
With my normal under 1% mineral ash Douglas Fir wood I have no problem with the light fluffy ash. Douglas Fir a poor coals making wood.
This year I had one cord of mixed Birch, Shaggy bark Elm, and Beech woods. All much higher ash %. ALL making excellent charcoals. My charcoal consuming/burning stove is melting these ashes. I am having to steel rod break this melt up to chunks to remove this cap-melt.

So a too good, too complete, fuel converting system can work against itself with freed up affected/reacting residuals problems then.

Maybe . . .
Steve unruh

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Bamboo has long been considered an undesirable fuel because its ash melts and forms hard masses called clinker that can damage the furnace. Bamboo Energy found a way to reduce clinker by using a blend of 30% bamboo and 70% Japanese cedar bark to increase the melting point of the ash.


I need to cut more wood today . Not keeping track of days boiler in operation . Used half my wood . Ran boiler for week and cleaned out ash from last year , Maybe I clean out ashes on Christmas .

Use baby monitor to keep track of boiler temp


Good Morning J.O.
You challenged me to think in different ways about down drafting for heat.
I do not have the personal means to do this. No budget to construct.

So I’ve had to just use research readings.
Many indications that at high gas speeds with turbulence “impossible” things happen in comparisons to more moderate speeds, with moderate turbulences. That near plasma event is happening.
Plasma generation as I read it ultra high frequency in gases produced.
Again not something I have a budget to pursue.
Read Joni’s last revelations.

Larry Dobson maintained the same occurring at his low, low turbulences, long time in residence, but metals killing temperatures. 2000C 2200C

And F.T indicated extremely high pressures are a T,T,&T potentialize too.
I have fear back off at other’s DIY’s 300 PSI creations.
Those with budgets indicate 1400 PSI 10 bars for the phase step.

Wife is ear pulling now.
Have to go.


@SteveUnruh: Wife is ear pulling now.

All wives are born equal. :laughing:


I wanted to put in a plug for the old U-25-B Project

I am pretty sure you are not allowed to do that because of nitrogen oxide emissions .
It was done before .

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Steve, my reasons for advocating downdraft are only practical ones. To be able to light a 100+ pound batch of wood and forget about it. Go to bed or go to work, knowing it will heat my 1,000 gallon storage tank enough to last 24-48 hours in wintertime. Also no creosote in the heatex tubes, flue pipe or chimney. Only easy to sweep fly ash.
There’s no way I would be able to 100% wood heat 3,000+ sq ft without it. Being away from home most of the day it’s just not possible.
I’ve run my “new” boiler for 17 years, with no maintence whatsoever, apart from cleanouts. I’ve experimented with chimney helper fans over the years, but mostly natural draft only. No ultra high speed plasma events needed.


I have pre combustion and re combustion and four heat exchange’s , flue gas turning to brown ice is a problem . when the exhaust of your wood stove turns to ice it is a problem .

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I’d like to see something about your system JO. Sounds like a winner.

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Well TomH. I have searched and searched for J.O.'s previously put up pictures and diagrams of his house system.
I even went through all 1040 posts in his “JO’s 8” gasifier".
I’d suggest this to anyone wanting to see a vehicle’s whole full evolution with pictures from trialing, making up then 8 seasons of hard running and improving as needs shown.

J.O. please do link your whole house system here.
Wood freedom fuel.
That’s what you evolved your house system to be for you. With one tall chimney for your natural draft performance and safety.
Steve Unruh


@tcholton717, @SteveUnruh

You’ll find a sketch of my system and a video I made 5 years ago in post 34 and 35 of this thread.


We are here Drax is across the Atlantic . We are selling wood pellets . If we were selling more natural gas , prices would go up . I do not see wood as an energy source and see no obstacle to Natural Gas . eventually the price of Natural Gas goes up .

A new report by Spatial Informatics Group, LLC (SIG), commissioned by the Southern Environmental Law Center and the National Wildlife Federation, takes a closer look at the carbon profile of wood pellets produced at Drax’s three U.S. wood pellet mills.3 Building on previous studies, SIG conducted a carbon life-cycle assessment tailored to Drax’s presumed wood sourcing for these mills.i SIG found that the accumulated emissions of burning wood pellets from these mills to produce electricity in the UK increases carbon pollution in the atmosphere for more than 40 years,ii well beyond the timeframe identified by the IPCC as critical for carbon reduction.
The evidence is clear—burning wood pellets for large-scale electricity-only generation is bad for the climate. According to SIG’s new report, the life-cycle carbon impact of burning wood pellets manufactured at Drax’s three U.S. mills exacerbates climate change for more than four decades at a time when countries must rapidly decarbonize their energy systems—and well beyond the timeframes relevant for averting the most dangerous consequences of climate change. Against the backdrop of the IPCC’s urgent warnings, burning forest biomass cannot be part of the solution to climate change.
Rather than continuing to subsidize burning wood pellets for electricity, countries like the UK must focus on transition­ing to genuine, zero-emission renewable energy sources, such as wind and solar, and protecting and expanding forests. The UK government, however, has diverted funds away from these true renewables in favor of providing hundreds of millions of pounds of subsidies each year to biomass. Given SIG’s findings, these subsidies are not aligned with current science on reduc­ing carbon pollution regardless of how the forest-derived biomass is sourced. The UK government should immediately end subsidies for biomass used in large-scale electricity-only generation and redirect that support to genuine clean energy produc­tion like solar and wind.

All economic sectors consume natural gas.
Combustion of natural gas emits about half as much carbon dioxide as coal and 30 percent less than oil, as well as far fewer pollutants, per unit of energy delivered.
Opportunities and Shortcomings of Natural Gas
Technological advances have greatly increased U.S. natural gas production, keeping prices historically low and spurring many electric utilities and industrial companies to switch from coal to natural gas. To a lesser extent, policies have also played a role in the shift to natural gas. Because burning natural gas yields fewer carbon dioxide emissions than burning coal (one-half) or petroleum (one-third less), the transition to natural gas has accounted for much of the decrease in greenhouse gas emissions from the U.S. electric sector in recent years. Renewable electricity policies have also contributed to emission reductions. As of 2019, natural gas is responsible for 38 percent of U.S. electricity generation, making it the largest electricity source in the country.

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I have experience with a lot of natural fuels. Wood is king - in my book.

Yes, down draft wood boilers do work. About 30+ years ago, Dad (with some help from me) supplied a bed and breakfast with fire wood. They had a batch down draft boiler and it worked as advertised. Heated the whole place and it was an old mansion.


Great JeffD, That you are better, and readin’, thinking, and chiming in.

Now tell me about that systems chimney. The actual pumping heart of the heat making end of it.
How tall: fire box to cap?
Inside diameter?
Construction material? Says how heat retaining it is. Brick versus metal.
You know . . . the other half of any good safe natural drawn system.
Down draft for heating; and half the story, is no story.
Best Regards
updraft SteveU.

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Steve, that was about thirty years ago. I know the owner used it for about five years[1] and really liked it. It was made in Germany or there about’s. At one time I had the patent on it but have no interest in trying to find it. I recall that the fire box had some kind of refractory with metal in the outside. Thousands of gallons of water in the basement, where the burner was. That is all I remember. Oh, he wanted/needed extra long wood, so maybe two to three feet. Do not recall the diameter of the fire box.

[1] The amount of time Dad supplied the wood.


Jeff I understand completely not remembering; or even having full system knowledge from back 30 years.

But did you understand me the no wood heating combustion devise is complete without a balanced functionable chimney?
Without something natural draft or motor driven pulling the expended combustion gasses out clean? Pulling in fresh 21% oxygen air?

You just posted quite accurately that a woodhauling vehicle no matter it’s GVW can only be as good and safe as it’s wheels and tires. So very true. 8-ply rating for me. 10’s better.

Same-same here.
It baffles me that everyone wants to talk engines&transmissions, and I’m saying what about the hold up safe and weight carrying safe wheels and tires. The chimney.
Any natural drafted combustion devises’ chimney.
I am more than baffled. I am shocked.
Down draft pulling those wanna’ rise straight UP combustion and post combustion gases needs a superior chimney system.

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I can not say for sure if it had a powered flue. My guess is that it needed it for start up. This old mansion was about three stories high with a tall roof. I’m sure it was a tall, tall flue. It was a commercial bed and breakfast downtown, right in the middle of a lot of law offices and close to the court house. So it must of had a well engineered flue. Well, I hope so - you know how that goes.

The old time truckers liked small engines and lots of gears. :yum: Keep a fella awake during long runs.


Oh, I remember watch a show about old chimneys. You know, real ones that do work. A person stuck a brick in it and the dang brick went right up that big old chimney. That really sucked.


Thanks. Excellent answer.

My Dad was his last 20 years a long/wide/heavy long haul lowbed specialty trucker.
He insisted on his Mack Maxidyne with it’s doubled up Spicer trans set up.
Dad? How do you handle those three levers? All in the touch, son. All in the touch.
Steve Unruh


I have a thirty foot long flue on my wood stove. Because of the convoluted smoke path I think at least that length is necessary. No problem getting the fire started each day even with no residual coals. But it is all updraft, natural convection. I have seen diagrams of peoples built in wood cook stoves with a smoke path that goes down, across the bottom of the oven chamber, back across the top and still seems to draft. Never understood that until I built the Rocket Mass heater. That is down draft, horizontal draft and then updraft and will work without a draft booster fan. That horizontal run is 15 foot long, makes a 180 and then back 15 foot to a 8 foot flue pipe. It won’t start without the duct fan on top of the flue pipe all though rocket heater purists would not use one. The run is probably a little long for a six inch diameter piped system. The barrel over the heat riser will show about 350 to 450 F when it gets running on it’s own. Add the 130 CFM fan and it will jump up to 650F in about a minute. By the time the hot gas goes through the thirty foot of duct that is buried in a bed of cob nearly all that heat has been bled out and flue temp will be around 90F. With the fan off, flue temp will be about 75F. Kind of amazing I think.


Talking about chimneys - my dad used to tell the story about this guy that was always really slow paying his bills when he had his new house built and then the mason knowing this, laid a piece of glass halfway up the chimney. Then on Christmas eve the guy was showing off his new house to guests and decided to light a fire in his new fireplace only to smoke up the house. He angrily called the mason who agreed to fix it in two minutes if the guy would produce payment for the fireplace - which he agreed to and the mason dropped a stone down the chimney. :laughing: