Why Cali Rated GM’s Volt on Par With Plain Ol’ Gas Cars


General Motors’ Chevy Volt, slated to launch in select markets next month, is a plug-in hybrid vehicle estimated to have cost more than $1 billion to develop. Yet despite GM’s years of work developing — and now heavily marketing — a car that can run on electricity alone for 40 miles or more, the 2011 Volt got an emissions rating from California air regulators this month that’s on par with conventional gas cars such as the Honda Civic and some Toyota Tundra truck models. What gives?

It might seem at first that by classifying the Volt as an ultra-low emission vehicle, or ULEV, the California Air Resources Board has ruled that the Volt is a dirtier car than some diesel and hybrid models that meet the more stringent standards for classification as super-low emission and partial zero-emission vehicles (SULEVs and PZEVs, respectively).

By at least one measure in ARB’s comprehensive rubric — the amount of carbon monoxide produced per mile — it’s true. The Volt produced more carbon monoxide in the test cycle than the 1 gram per mile allowed under the standards for SULEV or PZEV designation. Producing 1.3 grams of carbon monoxide per mile, the Volt’s carbon monoxide emission levels come in comfortably below the ULEV cap of 2.1 grams per mile, but a fraction of a gram too high for a SULEV or PZEV rating.

The same emission levels are allowed for SULEV and PZEV status, but additional evaporative emission controls and a 10-year, 150,000-mile warranty are required for PZEV status under the California rules, which 16 other states also follow.

As John Swanton, an air pollution specialist with ARB, explained to us in an interview this summer, “the point is to warranty expensive parts that are likely to cause emissions problems if they fail, but may not incapacitate the vehicle.” If the battery fails in a plug-in hybrid, for example, the car could conceivably stay on the road, belching out smog-forming emissions comparable to “a pretty poorly running gasoline vehicle.” For the 2011 Volt, GM is offering only an 8-year, 100,000-mile warranty — the result, GM has told us, of  “aggressive program timing” for the Volt launch.

One speed bump for GM in California’s rating system, as AutoblogGreen has noted, is that the Volt “doesn’t benefit from its battery-only ability in this test.” The ARB test cycle for carbon monoxide has the car’s gas engine running, although in practice, the engine won’t kick in until the battery charge is depleted below a set threshold, typically after about 40 miles. That could change with a proposed package of vehicle emission standards known as LEV III, which ARB expects to finalize by year’s end.

For GM and the Volt, the ULEV rating is a starting point. The automaker aims to earn the designation of “enhanced advanced technology partial zero emissions vehicle,” or enhanced AT-PZEV by the 2013 model year, GM Energy and Environment Communications Specialist Shad Balch told us in July.

According to Balch, the enhanced AT-PZEV designation could qualify Volt buyers for a $5,000 purchase incentive. He said GM “knew all along” that it would not earn enhanced AT-PZEV status from the get-go, and noted that the automaker is seeing plenty of demand for the first generation of the Volt without the incentive. “Lack of a government classification won’t change that,” he said. In a few years, however, “when we get through those early adopters,” Balch said GM is hoping $5,000 shaved off the sticker price will help pave the way for expansion to a broader market.

At the end of the day, the alphabet soup of emission ratings will matter for mainstream consumers mostly as a factor affecting what incentives (tax rebates, carpool lane stickers, etc.) are available for different models. It’s too early to say with certainty what designation an upcoming model will earn and what carrots might be in place for advanced vehicle buyers down the road. But Balch told us that GM has already begun working to “drum up support” from local and state governments for incentives (related to parking or charging stations, for example) that would be provided specifically for enhanced AT-PZEV models.

Image courtesy of General Motors

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Whatever you might say, the GM Volt displaces oil use. The CARB people are idiots. Remember that they are the ones that derailed electric vehicles in 2001, setting us back a decade, in favor of hydrogen fuel cells.

As Londo Mollari would say: “Ah, arrogance and stupidity all in the same package.”

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