How is it that subaru can get the PZEVC badge without shutting the engine off? I asked a subaru salesman, and he said that there are four emissions tests, and on two of them subaru qualified as having zero emissions, and as long as you can do it on half, you get the badge. My question is how did they do that? Even the most clean running engine produces CO2. Is that not considered an emission since it is not a pollutant in the traditional automotive sense? I'm just curious about the technology and testing procedures/guidelines/specifications.
I'm not trying to make any political statements, so PLEASE don't turn it into a discussion on CO2 and how much you love or hate Al Gore.
"The vehicles constructed to meet the PZEV requirements also fall within the Super Ultra Low Emission Vehicles (SULEV)-category. The Super Ultra standard is designed to be even more rigorous than the Ultra standard or low-emission vehicle standard. Various techniques are used to reduce pollution in these vehicles. In order to qualify as a PZEV, a vehicle must meet the SULEV standard and, in addition, have zero evaporative emissions from its fuel system plus an extended (15-year/150,000-mile) warranty on its emission-control components, which incidentally covers the propulsion electrical components of a hybrid electric vehicle."
From Wikipedia SULEV article:
"Examples of hybrid vehicles delivering SULEV emissions performance include the Honda Insight and the Toyota Prius.
A conventionally powered example is the Ford Focus SULEV variant. In 2005, General Motors' 3800 Series III V6 engines became the industry's first gasoline V6s to carry the SULEV rating and can be found in the Pontiac Grand Prix (optionally supercharged), Buick LaCrosse, and the Buick Lucerne.
PZEV is a more stringent variant of the SULEV standard, the Hyundai Elantra PZEV, The Subaru Legacy, Forester and Outback 2.5i PZEV, the Volkswagen GTI
2.0L Turbo PZEV, and the Volkswagen Jetta 2.5 PZEV are available in the U.S. state of California in compliance with this standard."
From my limited research it appears that shutting the engine while stopped is one way of reducing overall emissions it is not required and a vehicle can qualify without using it. The CARB is very thorough about these things and I don't doubt that they are calling it according to the existing rules.
I'm sure there are 'thresholds' and if the pollutants being measured fall below - perhaps in some combination - you pass. Keep in mind, just testing the air will detect some CO2. Then there is probably some error rate with the equipment like +/-6% or something. I dunno. Zero is never really ZERO with stuff like this. Just extremely low with the equipment and methods available.
The partial zero emissions standard is actually a fairly important stepping stone in the cleaning up of both traditional and hybrid propulsion types.
Not all pollutants are CO2. A portion of unburned hydrocarbons leave the vehicle through the tailpipe and evaporation inside the fuel delivery system and are significant pollutants. That doesn't make the amount of CO2 emissions less dangerous, but it's not all we need to talk about.
That is actually what I was referring to when I said polutants in the traditional automotive sense. It used to be reasoned, as early as the nineties that CO2 was not a pollutant. It was an unavoidable byproduct of combustion, and since it could not be reduced by altering how the combustion progresses, it was nto worth monitoring. Contrarily stuff ike NOx or hydrocarbons could be reduced by running closer to stoichiometry with better tuned fuel injection, optimizing timing, heating the engine up faster, better catalysts, etc... As long as you got rid of the other gasses and particulates, you could put as much CO2 out as you wanted since it was a relatively benign gas. Obviously there is now more attention on CO2.
The wikipedia quote cleared it up. I guess my confusion was because of the word Partial in PZEV. I had assumed(wrongly I guess) that this meant that Part of the time the car produces Zero emissions. Makes sense to me. I guess that is not the case. Or it is close enough to zero to be considered zero.
What's partial zero? Zoero is zero! A part of zero is ZERO. This is some bogus marketing aided by a clueless government that cant understand math concepts. "low emissions or Ultra low emissions" are valid but it is impossible to have partial zero. I would feel stupid having that badge on my vehicle.
I am pretty sure that partial zero means that in a part of the emissions testing the car produced zero emissions, or at least emissions that were below a threshold that they equate to zero. Like if most cars produced emissions measurable by whole numbers and typically ranged from say 5 to 11, and so they decided to just round to a whole number, then subaru came along and scored a 0.4, thus rounding to zero. Pure Speculation on the rounding to zero part. But I do know that they got partial because they were able to test as having produced zero emissions on 2 of 4 tests.
I wouldn't feel stupid for having a badge like that. I'd feel stupid if I had a honda and had a badge on the side that said 'powered by honda' that had been taken off a honda lawnmower or generator. Or if I had a relatively small engined 5 series BMW with an M3 badge on the back. Then I'd feel stupid.
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