Wood Gasification

Why Wood Gasification is part of This Permaculture Design

Wood Gasification is the process of converting wood (any kind of scraps or trimmings) into flammable gasses by burning it at very high temperatures in an oxygen starved environment.  These gasses, once cooled and cleaned of tars, can be piped directly into an internal combustion engine as a fuel substitute for gasoline…!!!

We have designed in the use of wood gasification units for:

  • Running trucks, tractors and other vehicles and machinery
  • Generating heat and electricity in the winter for greenhouses and homes
  • Being able to harvest the energy from sunlight stored in woody plants, from our own land
  • Using the waste product, biochar, to increase the fertility of our gardens and food forests which will also be pulling excess Co2 out of the atmosphere and locking it up

And the wood gasification units burn much, much cleaner than wood stoves because of the high temperatures.  They actually burn off almost all of the smoke and gasses, turning even these into additional energy.

Truck Runs by Wood Gasification
Truck Runs on Woodgas

Wood Gasification Explained

Wood Gasification producesenergy from local sources
Current Sunlight Energy
– Harvested by plants and stored in wood.

We learned about wood gasification at the MREA Energy Fair in Stevens Point, WI several years ago.  The good folks at Sustain Jefferson had their newly-built downdraft wood gasification unit on display and were sharing about its use and function.

The converting of biomass (mostly wood) into what is known as syngas (synthetic natural gas) has been around for over 100 years but was mostly forgotten once gasoline become readily available and inexpensive in our culture. Who wants to go to the trouble to start a fire in the back of their car or truck when with gasoline, all we need to do is turn a key.

But as recently as WWII, over 1,000,000 vehicles in Europe were converted from burning gasoline to burning wood when gas became almost impossible to obtain. It has been said that the German army had to convert many of their military vehicles, including tanks, to the burning of wood so that they could retreat at the end of the war.

As liquid fuels continued to be a challenge to obtain in Europe, sleek new designs were developed for affluent drivers. Woodgas was one of the key available fuel sources at that time.  But once petroleum become abundant and cheap, wood gasification became a thing of the past.

Today however, as gas prices continue to rise and as even its future availability seems less certain, many do-it-yourselfers are looking seriously at wood gasification as an honest and environmentally sound alternative to petroleum.

Wood Gasification on a Pick-up Truck

A Volvo running on Wood Gasification

How it Works

The process of burning biomass at very high temperatures in an oxygen starved environment to pull off hydrogen (H2) and carbon monoxide (CO) is knows as pyrolysis.

The folks over at All Power Labs have a great website that explains this graphic in full detail.

The gasification units or ‘generators’ can be made in a surprising variety of ways but here is a cross sectioned diagram of a unit also developed and found on the All Power Labs website.


 The point is… we are not inventing a new technology, but with the tools and materials we have available to us today, building gasification units is a very real alternative for many people and situations.

For Example

Wayne Keith's Wood Gasification Wayne Keith, a farmer from Alabama, was featured in the spring edition of Mother Earth News magazine because of his relatively long history with the use of woodgas in his trucks.  I highly recommend this well written article as it gives one a full view of the possibilities behind woodgas.

At the time of the article, Wayne had been running on woodgas for over 8 years. Here are some of the bottom line results he shared in the article;

          • He has converted 9 trucks to run on wood
          • Has driven over 250,000 miles on woodgas
          • Has saved approximately $40,000 from not burning gasoline
          • He regularly pulls heavy loads
          • He can run about 5,200 miles on a cord of wood
          • The Cost? His time in building the units and cutting wood to burn

Does it Really Work? Let’s take this in steps.

Since I had never seen an engine running on the burning of wood, it was a hard thing for me to believe. Thanks to YouTube and those willing to share, one can find an abundance of examples now.  Recently, I took our interns and a friend up to Wisconsin to meet Ben Hansen to learn first-hand from someone who has built and used several units.  While we were there, Ben had us help him take apart one of his wood gasifiers that needed cleaning and maintenance.  Afterwards we put it back together and fired it up.  Amazing…!  It really produced flammable woodgas.

Our friends up at Sustain Jefferson in Wisconsin also have a series of videos up on YouTube that share their journey as well.  Here is a short segment I pulled out that shows the starting of a motor from a wood gasifier and the generation of electricity to run a light and a fan (both essential in a winter greenhouse for growing more than just greens).


Here is Wayne Keith himself on a typical work day hauling bails of hay with one of his wood burning trucks.

And just so you know, the examples I’ve given you above are of everyday people like you and me, building these units themselves from mostly throw away materials.  Their homemade systems costing some as little as $100 and $300 to build.   If however you want a professionally made unit for your home, homestead, farm or small business, the folks over at All Power Labs have done an exceptional job.  (BTW… we are not distributors for APL…we just really like all of the information they have provided to all of us on their site.)

And We’re Using Current Sunlight, Not Ancient Sunlight 

This means that we can run cars and trucks by burning wood that we grow on our very own site and much of it can be from just two-year-old growth, i.e. brush.  We don’t have to wait years for trees to get full sized.  We can ‘collect’ the sun’s energy into woody plants in one year and turn it into power just two-three years later.  After all, oil (gasoline) is nothing more than ancient sunlight that was stored in plants and buried for millions of years.  Why wait…!!!???

For example, hazelnut production benefits from coppicing (cutting the plant off close to the ground) every 7-10 years for optimum production of nuts.  Also, any woody biomass or branches from a more mature food forest could be gathered and chipped (or chunked) and burned in a gasifier.

Environmental Benefits

Biochar can be a byproduct of Wood GasificationGasification is one of the cleanest, most efficient combustion method known. It is estimated that burning wood in a gasifier is 90% cleaner than burning it in a wood stove.  A gasifier burns the wood AND almost all of the smoke and gasses turning it into additional power.

But adding to these already significant benefits, the wood generator also produces a fair amount of charcoal, also know as biochar.  It is biochar that the ancients used in South America to build the fertility of their soils and boost their crop yields   With the use of biochar they turned the pale rain forest soils into a black humus…. terra pretta…!!!

And… when we pull carbon out of the air, put it into plants, then lock up some of that carbon into biochar when we burn it, and then put the biochar into the soil…. we are literally pulling Co2 out of the atmosphere and storing it in the soil!

Summary – This Is Huge…!!!

Follow this thinking, we can design a possible path towards an environmentally sound and humane future — a ‘permanent-culture’ future. Below is a very simplified outline but it hits the highlights.

  • Industrial Ag is transformed over the next century into the development of food forests
    • Eliminates poisoning the land, air and water with pesticides, herbicides, artificial fertilizers and GMOs
    • Topsoil erosion is reversed, building soil rather than losing it
    • The worlds water tables begin to recover and build
    • The worlds climates move towards stabilization, with droughts and floods becoming fewer and fewer
    • Wildlife and nature are restored
  • The food forests (which mimic a young forest, not an old growth)
    • Absorb excess Co2 from our atmosphere
    • Provide an abundance of food, shelter. fiber & medicines for people (more than industrial ag if designed well)
    • Develop a ‘waste product’ as they become more mature called… wood!
  • The excess wood can be converted to:
    • Woodchips as a universal mulch for gardens and orchards
    • Sticks that are 1″ to 2″ in diameter, to be burned in thermal-mass rocket-stove heaters for home heating — using 1/4 the wood consumed in conventional wood burning stoves (with relatively no air pollution)
    • Chunked up to burned in wood gasification generators
  • The wood gasification generators can be used to:
    • Create fuel to run cars and trucks
    • Run generators to make electricity and heat for greenhouses and homes in the winter
    • Run other internal combustion engines to operate a wide range of equipment and machinery
    • Harvest and lock up Co2 in the form of biochar which can be worked into the soil to help generate better crop yields and hold the stored carbon for centuries. By this method we might be able to reverse global-climate change if it truly is caused by excessive Co2 levels in our atmosphere.

All Season Greenhouses in our Temperate Climate

Finally, one of the big applications we see for a wood gasification unit is during the winter in a greenhouse.  A winter greenhouse needs heat, light and Co2 to produce abundantly in our cold and often snowy winters and a wood gasifier hooked up to an electric generator would provide all three.  More on this in the greenhouse portion of our design.
A Greenhouse could be heated by Wood Gasification
I, for one, am inspired by the creativity and work done by the people we have met who have been experimenting with woodgas and other essential aspects of living in recent years.  The real problems of the world will likely not be solved by governments or big business. they will be solved by you and me.  Let’s do it!   Thanks to Ben, Greg, Rob, Wayne and many others for their efforts.
Bill Wilson — Midwest Permaculture (updated 12/28/15)

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14 thoughts on “Wood Gasification”

  1. Just a note from someone who makes woodgas daily – the FEMA gasifier doesn’t produce engine grade gas. Commonly called a “tar maker” in the community. It can work, but you’ll stick up your valves fairly quick.

  2. Richard Wendt

    The website with the gasifier design is down, any other sources or site that has the design?


  3. Interesting! I’m currently reading a SF novel by John Varley called “Slow Apocalypse” which speculates on the results of the world’s petroleum supply suddenly becoming unavailable. Guess what the characters use to power their trucks and buses ?

    Wood gasification 😉

    1. Good to hear from you David. It’s so hard to imagine a future without oil when there are seemingly no signs in our day to day life that we are at a critical precipice. So…it’s good to know that there are folks working and writing about a future with less disposable energy. We will need lots of options.

  4. Am converting a one bedroom home with electric heat to a log style home. Main room will get a loft. Master bed room separate. I would like to supplement the electric heat with an efficient wood stove. Preferably one that properly burns the wood gas instead of pumping out the flu.

    With that in mind the Mass heater is too large for a tiny bed room and a tiny living room/kitchen. Besides Im only home part of the day so would use electric to keep it say 55 or 60F to prevent pipe freeze an to quickly raise the temps to comfortable 70’s in morning and at night after work with a wood burner. So with that in mind……. what do you recommend? I’ll be burning biomass (summer grass cutting approx half acre worth) and paper logs or bricket from a small schools restroom paper towel waste. Will also have small micro home on site (12×6″ log construction 12’x16′ in size) and want to small biogas burning heater for that too. THANK YOU in advance

    1. not sure it got set to auto recieve replies so I’ll add…

      so not having to heat WHOLE house all the time I would think a small heater for the separate master bedroom would be wise along with a second unit in the living room

  5. Hi, Great website. Lots of info. Wish I had some info to give you back. I’m 77 and this stuff has excited me more than it should. HeHe. I have everything to do this except the health. But maybe this will give me a jump start to do something before I buy the farm. Thanks and keep on keepin on. Ron S

  6. Bless you Bill (& Becky)!
    I’m working in the city, barely thinking about farms. But your work is CRUCIAL to me. When I meet the folks who say, “There’s NO WAY we’re gonna make it!” I can say, with truth in my heart, “There ARE ways! Look at this!”

    1. I understand your passion and your relief Richard. I was deeply relieved as well when I saw this path. And I know that it’s not the only path either. There is hope my friend. Great hope everywhere. In the works of Bill Mollison… “Though the problems of the world are increasingly complex, the solutions remain embarrassingly simple. Cheers… Bill W.