New VW TDI Commercial disses PRIUS

Posted as a separate thread.

http://priuschat.com/forums/gen-iii...-hybrid-jetta-gas-tdi-wrx-sti.html#post891501

HCH-II is cleaner than Jetta TDI but no so clear cut vs. Jetta gas.

Prius just sweep it clean. Pun intended.

 

They are? You must be looking at different certification sheets than I am...


http://www.arb.ca.gov/msprog/onroad/cert/pcldtmdv/2009/volkswagen_pc_a0070274_2d5_u2.pdf (ULEV 2.5 Jetta)...3-day diurnal - 0.25 g/test; 2-day diurnal - 0.40 g/test; running loss - 0.000 g/mi; ORVR - 0.01 g/mi

http://www.arb.ca.gov/msprog/onroad/cert/pcldtmdv/2009/volkswagen_pc_a0070279_2d0_u2_diesel.pdf (ULEV Jetta TDI)...3-day diurnal; 2-day diurnal; running loss; ORVR all "not applicable".


How do you conclude that the evaporative emissions are exactly the same for both the Jetta gas and diesel?

 

I was probably looking at two gas version of the PDF. You are right, they don't test Evp emission for Diesel it seems.

 

Diesel doesn't really evaporate, so the evaporative emissions would be very low. Maybe too low to test or it's considered negligible? Probably similar to many of the gasoline vehicles and PM's. Still worth putting in there though.

 

This is what the CARB regs say about this issue...

" …These evaporative standards and test procedures are applicable to all new 2001 and subsequent model gasoline-, liquefied petroleum- and alcohol-fueled passenger cars, light-duty trucks, medium-duty vehicles, heavy-duty vehicles, hybrid electric vehicles (including fuelflexible, dual fuel and bi-fuel vehicles) and motorcycles. These standards and test procedures do not apply to motor vehicles that are exempt from exhaust emission certification, dedicated petroleum-fueled diesel vehicles, dedicated compressed natural gas-fueled vehicles, or hybrid electric vehicles that have sealed fuel systems which can be demonstrated to have no evaporative emissions…." ( http://www.arb.ca.gov/msprog/evap/evaptp01.pdf )

Per EPA...

" …There are other environmental advantages of diesels as well: near-zero evaporative hydrocarbon emissions due to the extremely low vapor pressure of diesel fuel, low cold-start emissions, and low in-use emissions deterioration…." ( http://www.epa.gov/otaq/reports/adv-tech/420r04002.pdf - page 19)

To pursue this further, according to EPA's AP-42 (Emission Factors - http://www.epa.gov/ttn/chief/ap42/ch07/final/c07s01.pdf - page 7.1-63), diesel fuel's vapor pressure is 0.012 psi @ 80*F; gasoline is anywhere from 5.2 psi to 11.6 psi depending on the RVP of the gasoline. Accounting for the higher molecular weight of diesel fuel vapor vs. gasoline vapor (130 lb/lb-mol vs. 68 lb/lb-mol), the evaporation rate is about 0.44% as much as the lowest RVP gasoline listed (under the same ambient conditions).

Not trying to be argumentative here, but in my opinion, the evaporative emissions need to be included in the comparison of gas vs. diesel emissions. VOCs are at least as reactive as tailpipe hydrocarbon emissions from a ozone-production perspective.

 

<AHEM>You realize that with CO levels that low it become almost impossible to commit suicide by breathing Prius exhaust gas. Not only are the levels too low but the engine keeps shutting down ... it won't run all the time.

If you're going to commit suicide by breathing the exhaust, you're going to have to get a Jetta TDI.

Bob Wilson

 

*edited*

 

I love how he talks all big about owning a S4... F8L you could mention just a few of the cars you've owned that would kill that Audi...as could I for that matter.
I laugh at people like him.
S4 LOL

 

They (trolls) act as if the Prius is the first car all of us has ever owned. They never even consider the fact that we either own other vehicles or have owned them and have moved on in our lives while they are stuck in Infantville.

It's ok mate. He'll be gone soon.

Back on topic

Thank you guys for posting up the recent data on the diesel emissions output and the refining processes. Nothing is ever as black and white as it first appears.

 

Indeed. The 2010 Prius is the new standard bearer for others to match.

 

There are a lot of things that we don't know that they are unaware of. You gotta wonder if they ever thought if hybrid owners are onto something they have never imagine existed....

It is hard for a "full hybrid" owners to go back to a single engine non-hybrid cars because the flaws would annoy us. Infantvillians were born into the concept that human powered transmission, engine idling and frictional brake pads are perfectly normal. They don't question why engine RPM should rev up/down as the car accelerate. They don't question why the engine has to be running when it is not needed. They don't question why all the energy has to be thrown away to slow down. Why?

There are many things I don't know too... which I have no idea what they are. However, I question and find my answers. That's how I come to know the unknown.

I thought I knew "cleaner diesel" as well. The last time I looked up, it was still LEV (dirtiest allowed). I now know TDIs are ULEV but still not as clean as equivalent gas version with the same rating. I found those out because 1) I question and 2) I find out the answer. Diesel proponents came in and claimed TDIs are cleaner than gas engine cars. Had they looked up before coming to PriusChat, we wouldn't have this discussion.... and I may never question and find out ULEV TDI as well.

In summary, questioning one's belief (especially one that never questioned before) is a good first step. MSantos also questioned how HCH-II would stack up to paint a more clear picture for his reference. I only hope Diesel proponents also question their own personal unchallenged beliefs.

I will include the Evp data in the graph but the units are different. I have to think how to put them together.

 

usbseawolf2000, I am grateful to have a place such a PriusChat to work through ideas and misconceptions. There are many things I thought I knew about but which turned out to be wrong thanks to the wonderful input by members here.

I only wonder how many people go through their lives without researching their opinions or having those opinions critiqued by others.

 

usbseawolf2000 - per CARB, the conversion from the grams/test (for 2-day/3-day diurnal) to grams per mile is obtained by dividing the grams/test value by 50 ( http://www.arb.ca.gov/msprog/macs/mac0103/mac0103.pdf - 0.1 g/test per 0.002 g/mi NMOG).

The ORVR value is given in grams/gallon so you just need to divide the ORVR value by the mileage of the vehicle.

The running loss is already given in grams/mile.

 

wxman,

Ok.... so which one do I use? I still have to look up what those 3-days, 2-days, etc.. mean.

 

I want to see how the VW Jetta TDI is emissions wise compared to a Ford F250/Dodge Ram 2500/Chevy Silverado HD with their diesel options.

 

The 3-day/2-day diurnal tests are evaporative emissions from a vehicle that is not occupied, i.e., while it is sitting in a garage or driveway.

More information (the codified regulation) is available at Electronic Code of Federal Regulations: . It appears that the 3-day test is the main procedure (FTP) and the 2-day is a supplemental FTP.