Vw golf on coal gas


I have been working on a small updraft gasifier similar to the simple fire.

It is made of two 20l paintcans and use a single tube with four .50" holes in it.

I upload a simple nonscale drawning of it.

I have the lid left and the connection between the cans left.

The idea is to use charcoal and some bits of coke to power a golf mk2.

I have two mk2s one with a monotronic 1.8l 8v and one 1.6l carbureted so I will se what engine I mount it on.

I hope to get a range of 31miles / 50km.

When making charcoal, how big bits can you cook? Can I carbonize whole logs?
Also what turndown ratio does a typical updraft gasifier have?


I am afraid a gasifier this size will only get you 10-20km far. Keep in mind, there is a reaction zone that takes height, and then you need aextra 15cm of space over it as a insulator. Not to mention as ash builds up, it pushes thereaction zone up. This is why l went to downdraft when l am height limited.

Char making, it depends. How will you be making char? I found smaller is better, but more important thain size its important that size is uniform and that the wood is dry.

Turndown ratio is preety much only limited with gasifier height. Higher demand, higer reaction zone.


I have made coal in cans but the yield is not great, so I think I need a old tank on a couple m3 to get any significant amount.

It feels like a bit of waste to burning the wood to charcoal.
Seems like it takes three times the fuel to get charcoal, thankfully so grows wood on trees.:evergreen_tree:


If I’m interpreting this correctly you want to power
an approximately 112 hp engine. That takes a lot of woodgas,
which I seriously doubt you will get from a small updraft
gasifier. Just for fun check out the spec (sizes) charts for the
downdraft gasifiers in that hp range. The charts are on this site
and are sized by HP requirements.


Yeah it’s a bit small but my engine is about 80hp so I hope to get 35-40hp from it.

Is the imbert nozzle size correct for a updraft gasifier?
If not how do I calculate optimum nozzle size for a updraft gasifier?

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I never heard of an Imbert updraft gasifier. It seems backwards to me.


Sorry I was refering to pepes post about downdraft sizing chart and wondring if those dimensions would be correct for a updraft gasifier.

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I’m not familiar with the updraft builds, but I would venture
the dimensions and design would be different for each.
Someone else will have to chime in here.


This system would need steady feeding, and something like a rebak chunker and dry wood to work, but it wouldn’t take much modification to make into a shop heating device, or to recover the heat for any other purpose.

I really like the simplicity of the Seachar TLUD. If a person has a way to use the heat for cooking, a lot of high quality charcoal can be made. Again, TLUD’s require dry, and small sized fuel.

I have been experimenting with a type of cone kiln for making bulk charcoal. The only issue is that they need to be steadily fed, but will make good char out of long wood and green branches. Branches and regular sized small wood are the best feed stock for a cone kiln. The steel sides reflect the heat making the burn more efficient / intense, while containing the fire to a certain extent. The burn is pretty clean, little smoke.



charcoal making in very good condition


I have built and used about a dozen different charcoal making kilns and retorts. For dry, classified wood chips, a fan assisted TLUD made from a 30 gallon water tank works great. For 2"-3" diameter sticks, I recommend the hybrid kiln/retort that you will find described in the Charcoal Making Anecdotes topic in posts 101-104. These two burners produce about 15 gallons of char per batch but can be scaled up if you have access to bigger vessels.
For the quickest production using various feed stocks, an air-curtain kiln works best, but requires stainless or refractory lining and protective clothing for operator because of the extreme temperatures produced.


Thanks for the ideas!

Making some charcoal just now, testing driffent sizes so it will be intresting to see how it comes out.


I really like the charcoal maker in this picture. Each new retort batch is started with the gas given off by the previous batch sitting next to it inside the burn chamber. Once fired up, this system can be operated perpetually without additional fuel. The retorts can be loaded and unloaded remotely in order to maintain a clean and safe work area. Very nice!


The center vessel should be exhausting the pyrolysis / retort gas downwards for best effect, and a heat reflective shroud set around to maximize the heat use.


Charcoal seems like such a waste of energy!


I see it as more of an efficiency gain (in cracking the less desirable compounds in gas stream) and a means of gaining flexibility for primary feedstocks. Stack the deck for a given run using charcoal to lay a really robust char bed and then you can use crappy wood, plastics, or Wayne’s famous dead cat fuel. WKs happen to be really good at generating the char layer in situ compared to other designs; simplefire et al are simple/compact because of all that charcoal pre-processing/reduced need for high temp cleaning of the gas stream.


Hey Pepe,
I’d have agree if anyone is making wood charcoal by open air burning.
3 parts wood to make the “burn”. To reduce down 1 part of the wood into just a third of that 1 part of volume/weight into charcoal is wasteful.
But doesn’t have to be this way.
KVL’s way.
Kristijan’s way.
Mr Menke’s way.
Or even those in a house heating wood stove making does not have nearly the throw-away 3/4ters heat value.
Lots of driven off gasses-for-heat recycling systems out there if a fellow just looks.


For some reason l always looked at charcoal being far superior as transportation fuel over wood. Specialy for a unexperianced operator. I know woodgas driveing is a thing and many prove this, includin me, but if l were to design a solid fueled vehicle for public use l wuld not think of wood.
I look at charcoal vs wood gasifiction like petrol vs crude oil. Yes, thre were enines and vehicles made to run on crude oil, but for obvious reasons refineing to petrol is a nessesity. So, for me, charcoal is just that. Refined wood. BUT it isup to us to make it efficiant!

Allso, one big advantie with char is you can preety much use anything with carbon as feedstock.

Ofcorse, stationary systems are a entirely different thing!


Nothing wrong with what you have said KristijanL.
A fact check proof:
internet search up, “wood charcoal making machines”.
You will have pages and pages; and pictures and pictures of largish scale charcoal making systems.
Some using woods and wood products as an input stock. Others using Agriculture and Urban portions as their carbons inputs.
Some of the woods inputs systems making actual wood chunks charcoals. Most making carbons “fines” to then be slurry pressed/extruded and dried into fuel pellets, briquets, and rods.
ALL of these systems using all of the base off gasses as a heating fuel for their systems.

I will argue the use of the word, “necessity” though.
The original internal combustion engines were developed to fuel with powdered fossil coal dusts; biological made alcohols; plant made and animal made oils&fats.
Hard to use-meter and store two of the four of these.
Three out of the four of these could be DIY/farmer made virtually most anywhere. A No! NO!
So the “necessity” was driven to engines, and engine use develop to only be able to use a multi-tier level financed-developing; financed manufactured; and financed systems distributed Users-fuel. Money making more money.
To encourage more use: make it easy user, to use. Make it super cheap. Make it widely available.
Hey!! Just like easy-use Internet’ing versus telephone exchanging; or good-god-no, actual letters writing exchanging.

Pretty simple actually IMHO. Woodgas from your own grown stocks IS THE DO-IT-YOURSELF freedom fuel. Sweat it out. And it will provide.
Wood Charcoal? Can be too. A few make, and use it as such.

But then advanced engineered, better performance fuel charcoals? With guaranteed engine use performance specifications? Available as traveling roadside available fuel? Nope. Be just another highly taxed, highly regulated keep them-enslaved fuel-use chain.

And as living in the USofA. If I could shave 10-15 years off of myself I’d be developing a portable charcoal engine fueling system that could use commercial bagged “who knows what” cheapest BBQ briquets. Able to handle the super high ash residues of that commercial made-cheapest stuff.
Quite the challenge.
Then on excellent DIY wood-charcoal some make here that system would probably zoom-zoom, perform easy.
The 1940’s Swedish Kahlle systems required specially graded and screened for-Kahlle’s fuel charcoal to be able to zoom-zoom.
I accept this super duper special-specification fuel required in my super light man packed chain saws. I accept this in nothing else I use and own.
I burn most anything emissions safe in my in-house bulk woodstove. Be burning for house heating a lot of obsolete held back from landfills books this winter. The 3 cents a pound previous bulk buyer of these had gone defunct.
Ashy. Ashy. Ashy. Stir&clean. Stir&clean. Ashes to the landfill. Too many unknown metallic’s and such in their glossy covers and inks.
USofA newsprint with soy inks is OK. Brown paper sacks and packing non-glossy corrugated cardboard is OK. Everything else is too suspect to go into my chickens. Into my soils…


I can make anywhere between 25 and 50 liters of very well cooked charcoal a day on my 1 slow combustion fire down stairs , and if i needed extra fuel i could also collect the same from my other fire that runs all day upstairs as well , i started off cutting and splitting dead gum tree’s on my property and could never get more than 20 liters a day until i started burning hardwood pallet wood along with it ,that a company down the road throws out everyday and now i can make plenty with ease and now its a win win that the fire makes the electric that i use to cut the pallet wood to length and charge up my battery banks , and heats my house up toasty warm :smile: