The new rules limit the amount of carbon dioxide, methane, nitrous oxide, and hydrofluorocarbons (typically used as refrigerants in air conditioning systems) that new vehicles can emit per mile beginning with model year 2009.

The limits tighten each year after that, and by 2016, greenhouse gas emissions from lighter vehicles will be cut by one-third, while greenhouse gas emissions from heavier vehicles will be cut by about one-quarter.

Manufacturers earn debits for falling short of the requirements, and have up to 5 years to earn enough credits to erase the debit, after which they will be subject to civil penalties.

The auto industry responded by challenging the regulations in federal court, a suit which has yet to be resolved. Despite the industry protests, however, the CO₂-reduction targets set by the California rules are still more lenient than the voluntary target automakers set for themselves for Europe, and more lenient still than the EU’s overall target.

The EU has set an ultimate goal of 120g CO2/km by 2010 at the latest for new cars. The European, Japanese and Korean car manufacturers’ associations committed to an interim goal of reducing CO₂ emissions to 140 g/km by 2008/2009. (Earlier post.)

The California rules, however, specify 201 g/km in 2009 for passenger cars, reach 141 g/km in 2013—four to five years after the comparable voluntary target in Europe—and drop only to 127 g/km in 2016.

The basic California-rule calculation for greenhouse gas (GHG) emissions factors in CO₂, CH₄ and N₂O plus direct and indirect air conditioning emissions allowances if the manufacturer uses a low-leak system, refrigerants such as HFC-134a and so on.

For alternative fuel vehicles, the state rules apply an upstream adjustment factor: a multiplier reflecting greater or lesser upstream greenhouse gas intensity. For natural gas, the adjustment factor is 1.03; for LPG, 0.89; for E85, 0.74.

In other words, the manufacturer of an E85 (note, not flex-fuel) vehicle gets to multiply the total CO₂ emissions plus the air conditioning indirect emissions by 0.74.

This could have a significant impact on meeting the new criteria. As a quick example, let’s take a 2006 Flex-Fuel Chevrolet Avalanche, which delivers 12 mpg US combined on an E85 blend.

EPA figures project annual GHG emissions of 7.9 metric tons on 24,135 kilometers driven. That works out to 327.3 g/km of GHG. Apply the 0.74 fuel adjustment factor, and that number plummets to 242 g/km—the California target, as it happens, for a vehicle of this size for 2011.

This is a quick-and-dirty exercise that won’t match exactly the calculations California is requiring. But the power of the adjustment factor could be enormous in helping automakers meet the target. (Just as the flex fuel rule in federal CAFE helped them meet overall fleet economy targets and spurred the production of millions of low fuel-economy E85 vehicles that rarely use E85.)

Under the California regulations, flex-fuel vehicles, along with bi-fuel, dual-fuel and grid-connected hybrids (plug-ins) are evaluated based on tests when operating on gasoline. Manufacturers of plug-in hybrids have a special adjustment factor that can increase based on the capabilities of their battery systems.

For Zero Emissions Vehicles—i.e., hydrogen fuel cell, hydrogen combustion engine and all-electric vehicles (EV)—California has another set of upstream adjustments.

The ZEV upstream emissions factors are:

• Electric ZEV: 130 g/mile

• Hydrogen ICE: 290 g/mile

• Hydrogen ZEV (fuel cell): 210 g/mile

In other words, hydrogen cars are already defined as not meeting the long-term (2016) criteria, absent emissions allowances for A/C that could bring them back down. (For light duty trucks, however, it is a different story.)

The hydrogen penalty derives from the CO₂ associated with hydrogen production. There is a loophole that allows approval of a lower upstream emissions factor if the manufacturer demonstrates the percentage of hydrogen fuel (or electricity) produced by renewable energy resources.

EVs, however, are good to go.

Resources:

• Final Regulation Order