Emissions on VO versus diesel or biodiesel

Politics of WVO, legal aspects, emissions

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Emissions on VO versus diesel or biodiesel

Postby SunWizard » Tue Mar 04, 2008 10:34 pm

The engine being properly maintained and tuned is the main factor for low emissions. Even when this is done, emissions very widely in tests since there are a huge number of variables, engine, VO oil type, VO oil temp, test methods, even what fuel was run in the engine before it was switched to a new fuel.

The main concern is PAH (polycyclic aromatic hydrocarbons) which are known carcinogens. For PAH, B100 is lower than diesel, and VO is much lower than B100 or diesel (10-70% as much emissions.) Here is some relevant research on emissions:
emissions study

That research is old (95) but good, and didn't use heated 2 tank rigs for VO, which would lower emissions even more. They did test some elsbett modified engines on VO.

There is lots of other research showing lower (<50%) hydrocarbon (HC) emissions on VO and B100 compared to diesel, which is the real difference, not B100 versus VO they are very similar in most tests. Search here on emissions there are lots of threads. Lower HC means lower PAH which are the main carcinogens, and lower acrolein. Lower smoke opacity means lower HC, which is why they test for opacity in states with tests on diesels, and under load is where it matters most so they use a dyno.

If you really are concerned with emissions, get a diesel with a catalytic converter which reduces 20 – 80% in PM (particulate matter), 90% in HC, 90% in CO (carbon monoxide), and 15 – 20% in NOx (nitrous oxide). My 95 Dodge Cummins has a cat, not all of them do. This is better emissions reductions than differences in fuel and it applys no matter what fuel you burn. And if your rig is smoking for more than a few seconds under any conditions, get it tuned up!

And to fairly compare emissions, you would need to add in the refinery emissions in producing diesel, or the methanol that is 20% of B100. Using waste VO produces none of those emissions. Ever smell the air near a refinery? I have read that the EPA has them "grandfathered in" for those highly toxic emissions, and is one reason why no new refineries have been built in many decades in the US.
YVORMV - Your veg. oil results may vary.
95 Dodge Cummins 4x4 SVO WVO conversion.
81 Mercedes 300D- stock and happy on V80/D20 blend.
Low fossil net zero house- 100% solar power and heat.
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Postby SunWizard » Fri Mar 14, 2008 9:00 am

Here is a link to a more modern report with WVO better than both diesel and B20 on some vehicles, and especially under load. (still not comparing with ULSD.)

Here is another interesting study I found, stating when B20 is created with ULSD its emission benefit is negligible (B20 vs. ULSD), and it increases NOx 1-6%.

Here are emissions reports as contained in the master's thesis by Ed Beggs from Plantdrive:
YVORMV - Your veg. oil results may vary.
95 Dodge Cummins 4x4 SVO WVO conversion.
81 Mercedes 300D- stock and happy on V80/D20 blend.
Low fossil net zero house- 100% solar power and heat.
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Postby jburke » Wed May 21, 2008 5:06 am

"They did test some elsbett modified engines on VO. "

The text only says "the Elsbett engine".
This would be their multi-fuel engine they developed in the 80's, not an SVO conversion of a commercial diesel engine.

It was DI and used dual unit injectors.
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Postby BMW Fan » Wed May 21, 2008 7:27 am

I remember a talk (around 1999) with Guenter Elsbett about their 3 cylinder engine and plans for renewed production.
He told me, that it would cost Elsbett at least half a Millon Deutsche Mark to bring their motor up to the then valid emission standards for Diesel.
( German standards )
If the only ( then ) available PLANTOIL engine could not pass..........
I am just repeating what Guenter Elsbett told.
Germany is raising the emission standards and in most major city’s the older Diesel cars are prevented from entering. Zoning permits are requested. That counts for gas engines, too.


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Re: Emissions on VO versus diesel or biodiesel

Postby mixelpix » Mon Dec 15, 2008 1:03 pm


Aren't PAHs what comprise the "new car smell" - wonderfully fitting, not at all ironic...

I believe, like cetane and octane, HxCx and NOx emissions are somewhat complimentary in affect. When you mitigate the reduction of one, it is usually at the expense of increasing the other. I agree, tho - PAHs are really bad. I am also fairly certain that blending gasoline constituents into VO greatly increases PAH and other carcino- and mutagens, CNS depressant and other fun! emissions when the fuel is compression ignited. (Really puts an earth friendly "e" in 'e'missions) I digress...

Ray Holan of Cleveland, Ohio published a fantastic book which I urge anyone interested in bio-fueling purchase:

ISBN 0-9777247-052650 copyrights 1st edition 2005. My copy is the 6th edition, 2006. You can email Ray directly, ray@burningriverfuels.com, but here's his conclusion after controlled testing of VW Passat, Jettas of different years, a Golf, an '01 and '05 Chevy, '03 Dodge 3500, & 2 '85BMWs. All were tested on conventional diesel and SVO for HC, CO, CO2, NOx and opacity. Here are his conclusions from the testing he performed in conjunction with the folks at Envirotest - the company contracts to the Ohio EPA and operates the equipment for the DMV testing:
"When the Smoke Clears
When all is said and done, I don't claim this modest little survey meets the rigors of academic research. It would be easy to point out any number of flaws in method and procedure. Regardless, it is a reasonable set of data that suggests some trends at least. The averages of each test suggest that plant oil fueling:

-Increases hydrocarbon emissions
-Slightly increases NOx emissions
-Slightly decreases CO emissions
-Increases opacity (particulate emissions)
-Slightly decreases CO2 emissions

and here is an html version of some of his writing I think you might enjoy, Diesel vs. Hybrids!

His book covers the tactical theory of alt fueling options, the logistics of implementation and subsequent evaluation and troubleshooting. He also also done extensive research on emissions, economy and performance of various passenger diesels, trucks and comparative analysis with other vehicles. If you want to be current with biofueling zeitgeist, pick this one up today (Jeffrey - note the similarities in caveat from Ray as you heard from David when anecdotally applying or deconstructing this data set and the authors conslusions, thanks!) It is available through plantdrive and goldenfuelsystems.

Personally, i feel that in the face of amoral volcanic emissions (i grew up in Hawai`i and the emissions from Mauna Kea in Kona are life ending at times!) and the scale of industrial carbon emissions (especially from the distribution of animal meat) from my personal carbon "footprint" (I like to think of it as a my carbon "camel toe" or carbon "moose knuckle") mean nothing, a drip in the ocean as it were, in the face of industrial scale pollution from the U.S., China and all the other rapidly developing and beef consuming nations of man. I only now consider COx emissions in an immediate context of marketable trade value. I.e., I will pay a little more to pollute less COx, but not a lot! Since the E.P.A. is okay with all the unregulated HxCx combustion small industry can muster of "waste" fossil fuels, I figure focusing on the issues of toxicity is far more rewarding and affectual as an individual, a regulatory beurocrat or elected official. As an indicidual member of a body politic which is stuffing its own lungs with teratogenic organic tars, i hope one day that we can all make a true "conversion" from fossil fuel economies to sustainable ones.

Either way, I was very pleased to read your first sentence in this thread and will continue to help my friends "modify" their fueling endeavors with more PAH consciousness, thanks!


p.s. on the subject of modifications, I prefer the original design of Mr. Diesel and his Black Mistress. Am no detractor of the Otto- or Beau de Rochas-cycles either, but think the Atkins method has done some amazing things for the world of HCCI, especially what the M-B folks are doing with the "DiesOtto" concept car.
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Postby RECYCLER » Tue Oct 27, 2009 8:39 pm

Don't over look the 26 different toxins stated by at least the state of california produced by burning diesel. Yes 26 carcinogens that were brought into the limelight by the number of claims/lawsuits/settlements that have come from firemen being diagnosed with optical nerve cancer and brain tumors. Easy search for this data since many studies have been done with similar results and no argument in the other direction. The emmisions that come from producing "BIODIESEL" (two words that i believe to be improperly linked) can be just as damaging if the producer doesn't do ALL thier homework and work a closed system. PAH 's and these other toxic byproducts brought by burning petroleum products can be researched by following the research that has been done at several different colleges and universities. I think I'll check out what Ray Holand has written but I must say being contracted to the EPA and the DMV makes me feel like i'm delving into dishonest waters. There are a lot of studies that have been done that were not connected to current organization with a record of disorganization and even corruption.
Use it up, wear it out, make it do, or do without! RECYCLER
Use it up , wear it out, make it do, or do without!
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Postby bigtone23 » Thu Aug 11, 2011 6:57 pm

Our 1972 MCI MC-7 tour bus was purchased in April of '07 with the intent to run it's 8V71 Detroit Diesel motor on VO in order to afford driving it 50K+ miles a year. We had our first Colorado Smog test done on diesel just before the conversion was complete. The attendant at the test site gave us a wink and a pass, though we all knew we were just barely over the limits for how dirty our exhaust was and the visual thickness of the exhaust leaving the pipe. He let it slide since our bus was old.

When we went back the next year with a fully converted bus and 35K miles experience with the system, we decided to be a little tricky. We got the oil heated up to 180 degrees and went in for the smog check with VO for the fuel. The same attendant came out to us after the test and had a dropped jaw. He didn't ask why, but was amazed at how clean our bus was running. "WAAAAAYYY below the limits, fellas."

That's all the proof I need! :)
Grease Vulture
1972 MCI MC-7 Motorcoach with a 8V-71 motor 9.3L/568ci 318HP
Converted to 2-tank WVO December 2007.
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