SULEV versus higher MPG

[franzh]

Lets assume a marketing scenario:
A prominent auto manufacturer offers two models:
1) A vehicle which is SULEV (Super Ultra Low Emissions Vehicle) certified, for sale at a $1000 USD premium over the standard ULEV vehicle;
2) A vehicle which obtains 4 MPG better economy than the standard vehicle, also for a $1000 USD premium.

Wonder which one the public would choose?

My personal feeling is that the higher MPG vehicle will outsell the SULEV vehicle by over 100:1, maybe as high as 1000:1. My impromptu research says that the general public has little care about a vehicles emissions, but when fuel economy takes a back seat, they yell. I attend and speak at many US Clean Cities conferences and hear the lip service, but when the rubber meets the road, the consumer always asks “How many miles per gallon does it get?, and NEVER have I been asked by the consumer “What is the certified emission level and what does it do for me?”!



Oh, they are the same vehicle, just marketed differently!

Franz

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[R1100S]

Myself and most other consumers care about the pocket book.

Lean burn Hondas are cool.

 

[GregLocock]

Various groups seem to get very concerned about diesel emissions, specifically the particulates.

I heard that the German manufacturers spent a lot of time calibrating their diesels so that they did not emit too many particulates, but that the French manufacturers just put particulate traps in. This has now blown up into a debacle - the popularity of diesels in Germany has forced them to RETROFIT particulate traps to the last two years of production.



Cheers

Greg Locock

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[patprimmer]

I guess it's so easy to get so involved with the evolution of a method, that you forget to look clearly at the desired result without adding extra qualifiers.

I would have thought that for SULEV, CO2 emissions should also be considered, and these are pretty well tied to fuel economy, so long as you count all the fuel, and neither nuclear power nor non combustion based renewable sources are not used to charge batteries or whatever.

Regards

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[Azmio]

to get the vehicle to pass harder and harder emission standards, the catalyst gotta have higher cpi thus backpressure increases. Higher backpressure means relatively lower fuel efficiency. I think Franzh has a point here.

 

[patprimmer]

I am sure Franz has a point here. He always does.

If the regulations call for more restrictive cats and that causes power losses that result in fuel economy losses, then for the same amount of work done, the CO2 emissions will increase and to some extent offset the reductions in unburnt hydrocarbons, CO and NOx.

Regards

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[Tmoose]

"....but when fuel economy takes a back seat, they yell..."

Driving around in Eastern Massachusetts I see PLENTY of mid-to-large sized SUVs. I might be jumping to a conclusion, but I don't think they were crying about fuel economy, at least on the day they signed the lease papers.

 

[franzh]

Tmoose:
Agreed, but I guarantee that not one of them have any concern about emissions. When their SUV's fuel cost per mile hits the sky, they will downsize. GM has announced a layoff because of poor SUV sales because of increasing gasoline prices, so maybe it is already happening. SUV's are a status symbol, just as the Prius is, but on the opposite spectrum.

Thanks Pat, I was trying to hit home a point on the public's perception of a vehicle.
Our new vehicle has a transparent sticker on the drivers door glass stating it is an "LEV" vehicle. LEV is a definable rating, where if it stated that it is "20 MPG" is not. I have no doubt it is rated at LEV, and it gets 20 mpg with regularity. If my fuel mileage drops to 16 due to an engine condition, I can promise that the emissions will not be LEV. Even though I am an individual that recognizes the importance of LEV and SULEV, it is still the pocket book that has the main impact on my driving. LEV is just a bonus.
My 1966 Ford Mustang also gets 20 mpg, but try and test it for emissions and it will probably blow the bench!
Franz

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[patprimmer]

My point that still seems to have gone through to the keeper is that CO2 is an emission, and modifying an engine to reduce other emissions, but increasing the CO2 might have a net real world deficit while still passing a so called tighter test.

I guess I an questioning the logic of the details in the standard, even though I am only presuming what the standard is.

Am I hijacking the thread or is that a logical extension of the original subject.

Regards

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[GregLocock]

I raised that as an issue with the Australian Board of Interfering Whatsits when they were asking for comment on proposed emission standards.

All this emissions stuff has a DIRECT bearing on emissions and efficiency, and, cost of ownership.

I'm not arguing that getting rid of the smog in LA in 1980-1990 was a good thing, but I question whether the same standard needs to be met by a vehicle that is used for trundling around Kansas nowadays (etc).

Does anyone know why CO got on the list?



Cheers

Greg Locock

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[Azmio]

Not only that, the crash test legislations nowadays cause the vehicle weight to increase significantly thus lowering the MPG or increasing the CO2 emission.

I know that myself and others are trying hard to increase the engine fuel efficiency, but we can increase it little by little and not really a quantum leap or revolution in IC technologies.

At the same time the vehicle crash test and emission regulations are active in offsetting the gain in engine efficiency.

I am thinking that there must be a point where crash test legislation plus emission legislation will someday cause the vehicle fuel consumption to increase instead of decreasing.

I hope that the legislators around the world know about this. The gas and petroleum reserves are definitely not increasing thus crash test and tailpipe emissions should only get stricter at reasonable rate.

I just want to have comments from others, with the current reduction rate of roughly 50% reduction in tailpipe emissions (for example Euro 3 to Euro 4) in every 3 years, do you guys think that we will someday see an increase in fuel consumption?

I am thinking that we will someday hit the saturation point for improvement in IC technologies in reducing the fuel consumption. Thanks in advance

 

[franzh]

My whole point is not to discuss the importance of CO2 (which it in itself is a byproduct of combustion and warrants controls, but for which there are none yet for the automotive application) but to point that the publics concern is NOT for advertised emissions but for fuel economy, but that they are attainable in the save vehicle.

My 2002 Ford Explorer SUV is LEV, weights 4200 lbs (!) and gets 20 mpg regularly, never worse than 18 mpg, with all accessories. I bought it for the economy, the fact that it is LEV is of no real DIRECT benefit to me, more to Ford. Long term, and to the surrounding local, reduced emissions and improved air quality are of benefit. 30 years ago, a 4200 lb vehicle would be lucky to get 12 mpg, and fry any emission bench. Thank you very much for the electronics!

Have we really seen any improvement in the air quality in the last 30 years? Ours was just designated an air action area (I live in Central Texas) because of increasingly poor air qualtiy.

Franz

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[Azmio]

Many of the cities that I visited have signs that the air qualities are getting worse.

However, air qualities for cities in Germany, Switzerland and Japan that I visited can still be considered as good even though the cities have registered steady increase in vehicle ownerships. There was no sign of smog, etc.

With many EURO 4 cars moving around, I heard that the cars would actually generate cleaner exhaust gases if compared to the inducted air.

There has also been a report that someone did not succeed in commiting suicide when he directed the EURO 4 car exhaust pipe into the passanger compartment for hours.

Anyhow, my comment on your original topic is C02, MPG and tailpipe emission should all improve at the same time without one actually causing other to get worse.

 

[JayMaechtlen]

Re: air quality-
Even though the cars are getting better and lasting longer, the yearly miles driven per person seems to be increasing.
Also, some other pollution sources aren't controlled nearly as well as cars are.
(heavy trucks, buses, locomotives, etc.)
Many places (like here in Southern California) corrosion isn't a factor and cars are sometimes driven until they die (or fail smog test).
Smog test 'was' every two years on license renewal-
I'm notified that my '89 Aerostar must be smogged this year, even though it passed last year. I guess they're tightening up again...


Jay Maechtlen

http://home.covad.net/~jmaechtlen/

 

[SomptingGuy]

Getting back to the original question...

I drive a 1989 Volvo. New enough to have fuel injection, old enough to not have a CAT. A perfect compromise in my mind. SULEV servicing is F expensive - why would anyone want to pay more for servicing unless it came with a tangibly better car?

 

[NormPeterson]

I realize that this is only anecdotal support for franz's initial hypothesis, but the ONLY time that I hear anybody talk (or post) about emissions performance is either before a smog test is due (and they're perhaps worried a little about passing it) or immediately after (and the discussion revolves about some failure).

I don't think that I've EVER heard emissions performance discussed as part of the pre-purchase/lease decision process, one way or the other. But if the ability to maintain SULEV limits were to involve a greater amount of presumably more expensive maintenance, and that maintaining same were to become an emissions testing requirement (vs meeting whatever the standard car requirements might be), SULEV wouldn't need a $1000 price premium as additional disincentive.

Norm

 

[bobqzzi04]

Azmio wrote:
to get the vehicle to pass harder and harder emission standards, the catalyst gotta have higher cpi thus backpressure increases. Higher backpressure means relatively lower fuel efficiency.

I'm not sure this follows. My limited experience with modern metal substrate cats is that they have no significant back pressure. I ran a highly turbocharged VW engine on a superflow dyno and made 560hp with an open pipe. I added metal substrate cat which approximates the one on a VW 6 cylinder model and made...560HP.

I would also expect that since max fuel economy is achieved at cruise on the highway, when only a small total of available horsepower is being used, that the cat isn't an issue at all. (I'm sure some of the engineers on here can quantify how much HP it takes to push various cars/suvs down the road)

 

[JayMaechtlen]

'89 without a cat converter?
here in SoCal, the few '89 vehicles I've owned or inpected have cats...
Even the non-Calif spec Buick I had.

ref: sales importance of low emissions: nil except in certain very limited socio-economic niches.
(tree huggers with money)
Cheers
Jay

Jay Maechtlen

http://home.covad.net/~jmaechtlen/

 

[SomptingGuy]

Azmio wrote:
to get the vehicle to pass harder and harder emission standards, the catalyst gotta have higher cpi thus backpressure increases. Higher backpressure means relatively lower fuel efficiency.

The main problem with a three-way-cat is that it requires stoichiometric combustion, which completely rules out any efficiency gains that can be had from lean-burn technology. You can make the substrate as unobtrusive as you like, but you're still stuck with the fixed stoichiometric AFR.

 

[SomptingGuy]

JayMaechtlen wrote:

'89 without a cat converter?
here in SoCal, the few '89 vehicles I've owned or inpected have cats...
Even the non-Calif spec Buick I had.


Yep, a 1989 F-reg Volvo 740 GLE. Right-hand drive, UK spec.