Emission characteristics of vehicles fueled by wood

A very interesting question:
What do we know about tail pipe emissions from the oil companies.

Imperial oil 1967 internal document
"The petroleum industry, directly or indirectly, is a major contributor to many of the key forms of pollution. "
Shell 1968 internal document
” … Small sooty particles, meanwhile, are the “real villains in health effects”

Yes they are dirty.

But has anyone done any numbers on woodgas. I would like to see that, because I think ( PURE OPINION ) that the lifecycle of the fuel from the lifecycle of the tree to the block in your hopper is cleaner than oil. I doubt anyone here would argue that…

What is left are the tail pipe emissions. Since most of the fuel is CO H2 and short chain hydrocarbons that escaped the thermal cracking the emissions should before any considerations of emissions control devices be cleaner. The Nitrogen content of the fuel gas is high so you would think the combustion chamber temperatures would be low for less NOX. What you might expect might be high CO readings from fugitive un-burned fuel. Do we emit more of the tiny soot particles that diesel and gasoline are guilty of?

Would anyone like to try and take their DOW vehicle to an emissions test centre and see exactly what comes out of the tail pipe?
That’s my question are we as clean and green as we think?

Think of the variables:
Type of fuel wood VS charcoal. Wood moister content, steam injection Hmm…
We should ask an egg head at a university to write a research paper on it.


Wayne has done this and passed emisions testing with flying colors. I’ll have to look but I think there is a section in the book about it


Emission ?? What are harmful emissions and for whom? CO is a toxic gas for humans but harmless to nature if enough oxygen burns in the engine in CO2. H2 and CH4 form H2O and CO2 during combustion, again the appropriate amount of air is required. The biggest problem is NOx gases, which are formed in the combustion chamber at high temperatures and with excess air. These gases are harmful to humans and nature, as they cause the collapse of plants, and this gas must be given the utmost attention in the wood-powered engine.


We don’t have vehicle emission testing here in Alabama so I have no official test. But back several years ago a guy that was very interested in gasification came by the house and ask to do some test on the truck . I have forgotten exactly what the test where but he would have me switch to gasoline to test and back to wood and he was sampling the tailpipe exhaust . I think the test had something to do with the amount of oxygen that was being used . Also I think he tested for nox . I don’t remember the numbers but he said it would pass California standards.


Passes California standards!!!

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Wayne, at a biomass conference back in '09 or so, I met a guy from Auburn who told me you spent some time with them running all sorts of tests. The end result was wood was more efficient than gasoline as an energy source and I thought I remember him saying emissions were less, too.

I spent quite a bit of time at the US Forestry Service gasification test station in Louisiana. They used a BioMax 25 and, being federally funded, had to get the green light from the EPA. One of the research PhD’ guys said the EPA guys came out, looked around, got a brief tutorial on gasification and tested the exhaust from the 4.2 liter Chevy engine driving the generator. All clean!

He didn’t share any numbers but the EPA guys said it shouldn’t need any sort of permit… nothing being emitted other than the exhaust from the engine. And it was clean.


It would be very interesting to run more tests on this. It would be very nice to see some additional experiments on closed chamber heads, higher compression ratios, swirl heads, and fast burn heads… On traditional engines fueled with petroleum these all improve performance, but usually at the cost of higher emissions. Could wood gas do better?

I know no one here has the time or money to spend on it…
Government has money for all kinds of things like windmills and solar cells made in China. Why does this get ignored?

*Note: BioMax systems are made by Community Power Corp., Englewood, CO.

Has Community Power ever gotten into commercial production? I was told by a researcher I was working with that they wanted to stay in research in order to get grants. As I recall, Auburn and Mississippi State have BioMax 25’s from Community Power.

I have no idea if the USFS gasifier is even being used anymore. I was told the Forestry Service spent half a million ($250,000 on the gasifier and $250,000 the building and other stuff) for the 25kw gasifier/generator. Then, no more funding.


My understanding is that they like to work on large scale projects. They worked with Coors Brewing, Golden, CO, to burn up spent hops, for example. In this case the economic justification for the project was that it allowed Coors to avoid the cost of trucking the hops to farmers fields.

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The USFS BioMax 25 was first fired up in '08. I was brand new to biomass gasification and was working with a group on Fischer Tropsch with a nanotech angle (university research commercialization). One of that company’s goals was to do on site conversion of logging residuals and highway right of way clearing to convert all that biomass to liquid fuel on site. Again… taking the transportation out of the equation.

Interestingly, I hear logging is moving in that direction. Mobilizing a full logging crew is so expensive that it isn’t worth the effort unless you have 100 acres to log or more. So, smaller outfits are taking the sawmill to the woods and cutting it right there. Again… taking much of the transportation out of the equation.

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Not too discredit your research, but i would liked too have had an emission meter while out raceing 2 cycle gokarts, probley 4 times the california testing for newer vehicles, I lived in oakland county michigan, and the test were for newer than 10 year old cars, most older cars not putting on many miles anyway i suppose. on another note my 91 chevy 3500 gets about 10 mpg empty, and i would rather breath the wood gas tail pipe over the petro pipe, easy noticeable better. Not too menchen diesel fuel, though just what ever additives added too gasoline?