Exaust Emissions in BioDiesel Jetta vrs Prius

I found this link: Bio Diesel vs Hybrid (Grist Magazine). I don't know much about this stuff, so I can't promise it's accurate.

 

I've always been interested in this question as well, but don't know enough about the matter to be able to contribute.
Based on my limited understanding, I would guess that the Prius is better than a 'fossil fuel' diesel any day. Biodiesel however has the advantage that the living plants from which it is made, use up carbon dioxide during their life, and most estimates suggest that they use up an amount comparable to the carbon dioxide that is released when burning biodiesel, so running biodiesel would appear to be 'sustainable'. However, this does not take into account (AFAIK) the cost and energy to collect and process biodiesel, but honestly I don't know.
Particulate matter and sulphur: I think (but may be wrong) that particulate matter in diesel exhaust comes largely from dirty diesel and sulphur content. It makes sense that fossil fuesl have these, but biodiesel would not unless sulphur is introduced in the process of making it palatable to cars. It therefore seems convincing that biodiesel engines produce little particulate matter and less sulphur than the Prius.
Overall, I think it's hard to argue that a Prius would be better than a biodiesel car. Hhhhmmm, maybe my next car will be a biodiesel?
Maybe the best car would be a hybrid that uses a biodiesel ICE?

 

Either it was just me or that article was confusing. I still do not think that article answered the question of which one produces more emmissions.

Their closed carbon cycle does not make sense to me. If you think about it even gasoline were once creatures (plants and animals) that consumed carbon but took millions of years to reach the state of becoming oil. http://www.astronomycafe.net/qadir/q1161.html

To me the only way to check would be to hook up a SVO diesel to an emmissions tester and read the results. The only thing I like about it is that it would help reduce the dependence on foreign oil but not reduce emmissions (compared to the Prius). Now a hybrid diesel using SVO would probably be optimal for an environmentalist.

From http://www.biodiesel.org/resources/faqs/
How do biodiesel emissions compare to petroleum diesel?
Biodiesel is the only alternative fuel to have fully completed the health effects testing requirements of the Clean Air Act. The use of biodiesel in a conventional diesel engine results in substantial reduction of unburned hydrocarbons, carbon monoxide, and particulate matter compared to emissions from diesel fuel. In addition, the exhaust emissions of sulfur oxides and sulfates (major components of acid rain) from biodiesel are essentially eliminated compared to diesel.

Of the major exhaust pollutants, both unburned hydrocarbons and nitrogen oxides are ozone or smog forming precursors. The use of biodiesel results in a substantial reduction of unburned hydrocarbons. Emissions of nitrogen oxides are either slightly reduced or slightly increased depending on the duty cycle of the engine and testing methods used. Based on engine testing, using the most stringent emissions testing protocols
required by EPA for certification of fuels or fuel additives in the US, the overall ozone forming potential of the speciated hydrocarbon emissions from biodiesel was nearly 50 percent less than that measured for diesel fuel.

http://www.worldenergy.net/product/emissions.asp
http://www.soypower.net/BiodieselPDF/Biodi...elEmissions.pdf
I could not find any analysis that I could use to compare the Prius to the SVO.

 

Yes, but generally speaking it's the plants that fix atmospheric carbon, not the animals, and research suggests a much higher percentage of CO2 in the atmosphere at that time in the planet's history; the idea being that to preserve present climatological conditions we want the CO2 that was long ago fixed by those plants to stay fixed and in or below the earth's crust.

 

Biodiesel is quite amusing. I've burned quite a number of diesel supporters by pointing out that it actually *INCREASES* the level of NOx emissions (a major contributor to smog).

No person with honest intentions would ever compare biodiesel to gas. That just plain is not fair. It should be biodiesel to biogas (ethanol).

By the way, unlike biodiesel, ethanol actually reduces NOx. That's why E10 (10% ethanol, 90% gas) has been standard in Minnesota for years now and E20 will be starting in 2013.

 

Here's epa.gov

http://www.epa.gov/otaq/models/biodsl.htm

I think to be truly fair you have to compare all aspects, no just emissions or mileage but also production and maintenance across the board:
gas, biogas, diesel, biodiesel and electric.

And the all important component of how much pollution it takes to produce these fuels in the first place. If you're burning coal to produce electricity.....it's not all that great a tradeoff.

 

It's really hard to get some to look at the big picture.

And the reality of living in the rust-belt adds an interesting twist to "across the board" measurements too. Yes, it may last +200,000 miles on paper. But on roads covered with salt & sand and exposed to both extreme humid-heat and extreme dry-cold, the vehicle body falls apart before the diesel or hybrid system will.

 

Yes, but I think the addition of C27H45OH to the emissions cocktail as a result of using BioDiesel is being scandalously swept under the rug in the name of environmental correctness!

Isn’t cholesterol considered an environmental hazard?

If not, then maybe they need to do studies on the physiological affects of atmospheric cholesterol and on the psychological affects of the smell of BioDiesel.

Smelling Rendering Plant BioDiesel exhaust could be the straw that causes someone on the edge to commit murder!

French Fry BioDiesel smell could cause someone with a weak impulse suppression to eat themselves to death.

I can just see the headlines and late night infomercials. “Have you been the victim of BioDiesel exhaust? Call the law firm of BOGUS AND BOGUS and join our Class Action lawsuit today!â€

[ , :lol: ]

 

On the positive side, I can see the fumes provoking involuntary bulemia.

I could lose an easy 40 pounds just standing by a busy intersection.

Sweet!

 

Sounds like this would be a perfect topic for a would be PhD candidate engineering. Someone volunteer 'cause PhD is way past my pain threshhold.

 

Here's an interesting link my (biodiesel) partner sent me yesterday. The article is written by the inventor who claims to have invented a way of modifying a gasoline engine to run on diesel. The writer of the article is the inventor of the process, so you can judge accordingly. Nonetheless, it tweaked my fantasy of having a bio-fuel source for my Prius so that I could actually be free of gasoline not just on a severe diet.
We visited a guy who is setting up to make biodiesel in Port Townsend, WA. He has permits to do this and his setup is very clean and efficient. What surprised me and Lyle was that he adds about 10% biodiesel to his gasoline powered truck and it improves both his mileage and engine operation. Biodiesel has a very high detergent cleaning capability. I found this startling news, but am not ready to dump some of Lyle's biodiesel into HUMU's gas tank anytime soon.
Anyone else heard of this?
Bob



http://www.washingtonfreepress.org/73/gasE...neUseDiesel.htm

 

<div class='quotetop'>QUOTE(hdrygas\";p=\"92731)</div>

The emissions are so bad that there is a national sales restriction. VW was only allowed to sell a total of 35,000 TDI vehicles last year. So naturally, I wouldn't expect that data to be easy to find. They don't really want many people to know info like that, especially the vehicle-specific stuff.

http://john1701a.com/prius/prius-log148.htm ...provides a link for an EPA study that clearly states that biodiesel is actually dirtier than diesel with respect to NOx (smog) emissions. You'll find that interesting.

 

<div class='quotetop'>QUOTE(john1701a\";p=\"93103)</div>

The emissions are so bad that there is a national sales restriction. VW was only allowed to sell a total of 35,000 TDI vehicles last year. So naturally, I wouldn't expect that data to be easy to find. They don't really want many people to know info like that, especially the vehicle-specific stuff.

http://john1701a.com/prius/prius-log148.htm ...provides a link for an EPA study that clearly states that biodiesel is actually dirtier than diesel with respect to NOx (smog) emissions. You'll find that interesting.[/b][/quote]

John: I don't fully understand your almost viseral disdain for biodiesel. Fuel produced from vegetable matter that we can grow here without all the Middle East crap is certainly an avenue worth pursuing. Biodiesel is not a competitor, but a fellow traveler; neither is a complete solution to the oil crisis. There is not enough arable land to grow crops to make the huge quantities of biodiesel that would be required to make a major dent in our consumption. On the other hand, petroleum is not infinite and hybrid production is miniscule. There are processes using algae to make biodiesel, and there is a lot of experimentation in crop rotation, etc, going on in my home state of Washington. I find it all pretty encouraging and exciting, and certainly don't see biodiesel as a threat to my Prius or as some kind of pseudo-scientific fraud being perpetrated on us.
The restrictions imposed on TDI's and other diesel cars, are are not federal, but are imposed by California and several other states where the emission standards are high and preclude using the dirty petrol diesel currently available here. Once we get the cleaner diesel that they use in Europe, diesels will be sold in all 50 states. Biodiesel is big in Europe and they are pretty serious about environmental issues.
I'm including a few links to EPA reports that give a listing of all the emissions from both bio and petrol diesel. About the NOx, more recent EPA studies iindicate that the NOx levels are not higher than those from petro diesel. Smog is formed by sunlight reacting to hydro carbons which are produced in greater abundance from petro fuels than from bio fuels.
The biggest advantates, however, is that bio fuels do not introduce new carbon dioxide into the atmosphere and are renewable.

http://www.epa.gov/otaq/models/analysis/bi...odsl/p02001.pdf

also:

ttp://www.nwventurevoice.com/archives/2005/05/nrel_says_biodi.html

from National Renewable Energy Lab:

http://nbb.org/pdf_files/fuelfactsheets/emissions.pdf

 

<div class='quotetop'>QUOTE(Tadashi\";p=\"93075)</div>

Sorry Tadashi, I'm already 25% finished with my PhD in another subject... and yes, PhD is excruciatingly painful.

I imagine that there would be at least noticable sulfur emissions simply because all living organisms contain sulfur in proteins and other sources. But I'm in life science, not Processing-Life-Into-Fuel science.

 

<div class='quotetop'>QUOTE(Bob Allen\";p=\"93420)</div>

ETHANOL!
ETHANOL!
ETHANOL!
ETHANOL!
ETHANOL!
ETHANOL!
ETHANOL!

Biodiesel supporters pretend it doesn't even exist.

Ethanol is produced from vegetable matter (corn, wheat, or soy), just like biodiesel. However, it is cleaner and works in just about every single gas car on the road in the US today at a 10% mix. There are also 3 million vehicles in the US already that can use up to an 85% mix. Supporters of biodiesel hate that reality. They are fighting to get just a 2% mix mandated... and they realize beyond 20% requires additives for cold temperatures... and they realize that ethanol actually increases horsepower... and they realize it is the popular choice as a MTBE replacement. So, they try their best to ignore that ethanol has greater potential than biodiesel as an organic substitute for drilled oil.

I have already used 203 gallons of ethanol in my 2 Prius. It is clearly a realistic option.

How come you didn't mention ethanol either?

 

I don't see anyone here villifying ethanal John. However, ethanol IS being subsidized by the government, hiding it's true cost. Like with all biomass introduced fuels with current technology, it is NOT sustainable as a replacement for gasoline. In effect you are guilty of doing the exact same thing, that these alleged anti ethanol people are doing.

The reality is that we NEED diesel powered vehicles. This big ol' trucks that bring us every thing we use as a society, would only get 3 to 4 mpg, if they were to go back to a gasoline type engine. Same for the stationary equipment, and locomotives - their fuel consumption would nearly double.

As fo NOx emissions, the NET output for NOx over the duty cycle of the engine is dead even with fossil fuel diesel. It's a little higher to start, but falls off gradually to a little lower at the end of the lifespan of the engine that the fuel is bieng used in. Irregardless of these figures, the elimination of sulphur from the fuel equation, allows for emissions controls to be installed on the engine, further reducing what little is left. Unlike ethanol, biodiesel CAN be used in pure form, without engine modifications. I know, as I've personally run my truck on the stuff, and did a 1500 mile road trip soley on B100.

Biodiesel has the same gelling issues as fossil fuel diesel. Only the additives required to deal with the parrafins, need to be tweaked for them to work reliably.

Just because you may have come across some die hards who won't listen, doesn't mean that biodiesel needs to be trashed at every opportunity. The reality is that if we as a whole are to ever get off of the oil tit, EVERY form of alternative fuel and power production will be required, not just one.

 

at the Alternative Fuel and Electric Car Rally Fair in Lacey, there was a couple biodiesel displays with great info.

biodiesel would be the way to go IF you can get it. facts are, it takes a lot to produce it using current methods. also transporting it would be a massive undertaking. one display had several "projections" (some a bit optimistic) on a scenario using small local farms to produce biomass with regional processing farms. but the land question makes it tough to justify. huge amounts of farmland would be required which in itself would eliminate biodiesel as the primary solution. it would be a niche market at best even under the most glowing of propositions.

do i think we should abandon it?? no...we cant afford to do that. we must look at several different ways to replace our dependence on fossil fuels as it is becoming more and more apparent everyday that no one solution will do the trick