After many years of regularly visiting CanadianDriver.com, this test drive has finally prompted me to register on the forum. I am writing the following as the owner of a 2005 Legacy 2.5i 5MT with a strong interest in the climate change question.
First off, the article starts by referring to "greenhouse gases". It should be understood that the PZEV emission certification, originating in California and now also mandatory in other US states, has nothing to do with greenhouse gases emissions.
The PZEV norm relates to pollutants. Theorically perfect combustion of hydrocarbons (HC compounds) with the oxygen (O2) in the air should produce only water vapor (H2O) and carbon dioxide (CO2). H2O and CO2 are not pollutants. CO2 is generally recognised as a greenhouse gas, meaning that it has a heat-trapping effect. Water vapor is also a greenhouse gas, much more present in the atmosphere than carbon dioxide. H2O and CO2 are both necessary to life on Earth. So, perfect, pollutant-free combustion of hydrocabons and oxygen would result in nothing else that greenhouse gases being emitted. The only way to reduce automotive greenhouse gas emissions is to use less hydrocabons and less oxygen to travel a given distance, that is to improve fuel economy.
As for pollutants, there is no such thing as perfect combustion. First, nitrogen makes up 78% of the atmosphere. Impurities are present in gazoline. Combustion processes can't be 100% perfect. This results in pollutants being emitted by combustion. These are mainly oxydes of nitrogen (NOx) and carbon monoxyde (CO), toxic and harmful compounds, thus pollutants.
Achieving PZEV certification will make an engine emit less pollutants (mainly NOx and CO) and more of the products of "better" combustion (H2O and CO2), which are the "feared" greenhouse gases. Less pollutants means more greenhouse gases.
There are undoubtedly some Canadians who think they will be fighting global warming by buying a PZEV car, but they are mistaken. Their new PZEV car will not help reduce greenhouse gases, but will have a mostly symbolic effect on air pollution, akin to trying to cleanup the St-Lawrence River by emptying a few bottles of Perrier in Lake Ontario.
Which brings me to my second point. The PZEV certification is not mandated in Canada, and obviously its only tangible benefits are to allow Subaru of Canada to projet a "green" image and make some Legacy owners feel greener. If only because of the larger catalytic converter, PZEV implies higher costs.
I will soon be in the market for a 2009 car, and am very disappointed by Subaru of Canada's Legacy lineup for 2009. Considering the Canadian MSRP remains abnormally high compared to US pricing, the base Legacy 2.5i should at least include features that are present on the base US Legacy, instead of the useless PZEV certification. More precisely, the base 2009 Legacy in Canada should have included electronic stability control (VDC in Subaru-speak), 17-inch wheels and heated windshield. It seems really incredible that in Canada, the base 2009 Impreza has VDC while the base 2009 Legacy doesn't. My 2005 Legacy 2.5i base model has the heated windshield, but this convenient feature is now missing in 2009.
To get VDC, 17-inch wheels and heated windshield on a 2009 Legacy, I would have to plunk $2500 more for the Touring Package, which also includes a better sound system, moonroof and foglights, (items for which I have little interest) but strangely, deletes mirror-mounted turn-signals.
It would have been interesting to read comments in the article regarding Subaru of Canada's reasons for selling a decontented base model in Canada as well as Canada-US price discrepancies.