Automakers play high-stakes CARB game to earn zero emissions vehicle credits

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CARB ZEV vehicle game board 2018

CARB ZEV vehicle game board 2018

Editor's note: Green Car Reports covers a lot of electric cars—and there are a lot more to cover these days, thanks to California's complex requirements that major automakers produce zero emissions vehicles for sale. For fans of clean cars—as well as opponents—it's difficult to understand how many plug-in cars the state requires due to a complicated system of credits. This directly impacts the selection of models available. In this report John Briggs breaks down how the system works by turning it into a high-stakes card game, complete with chips and a banker. 

Please note that the numbers in this story are approximate, because California uses its own tests to determine electric vehicle range, which directly affects the number of credit points manufacturers earn. Since these test results are not made public, we have used a conversion factor to approximate the points based on each car's EPA-estimated range. We have done the same with sales numbers, which are not broken out publicly for California.

While we understand that the numbers are not exact, we believe that they are directionally correct and provide a valid basis for comparison among manufacturers (much like the EPA's own fuel economy ratings).

Playing by the rules in California's ZEV Zero Emission Vehicle Game

Ever attended an adult board game night and found yourself playing a game with far too many rules?

The California Air Resources Board’s (CARB) Zero Emissions Vehicle (ZEV) mandate seems to be such a game. A complex set of rules require auto manufacturers to produce vehicles without tailpipe emissions.

The game

Auto manufacturers that sell more than 20,000 vehicles per year in California and have annual global revenue more than $20 billion must play this game, and are known as Large Volume Manufacturers. Sales are calculated as a three-year moving average for five years. Did I mention the rules are complicated?

In 2016, the last year reported by CARB, six automakers were determined to be Large Volume Manufacturers (LVM): Fiat Chrysler, Ford, GM, Honda, Nissan, and Toyota. (BMW, Hyundai, Kia, Jaguar Land Rover, Mazda, Mercedes, Subaru, and VW may join them in 2018 by crossing those sales thresholds.)

Imagine the six manufacturers are playing a little game. (Figure 1, top.) Each has played different cards generally of two types. In black are TZEVs (Transitional Zero Emissions Vehicles) which is CARB-speak for Plug-in Hybrid Electric Vehicles (PHEV). In red are the ZEVs (Zero Emission Vehicles) which are either battery electric or hydrogen-powered fuel-cell vehicles.

But which is the winning hand?

Before you answer, it is worth knowing more about the rules of this complicated game.

The value of cars

Not all cards (cars), have the same value. The ZEV credits increase with a vehicle’s all electric range (AER). Credits equal 0.01*AER+0.5. Each vehicle gets 0.5 credit plus 1.0 more credit for each additional 100 miles of range.

Plug-in hybrids have ranges of between 10 and 80 miles, or according to the game scoring, 0.6 to 1.3 credits. For ZEVs, which are battery-electric or hydrogen fuel-cell vehicles, the range is between 50 and 350 miles (1 to 4 credits).

CARB ZEV vehicle game 2018 point value of chips based on electric range

CARB ZEV vehicle game 2018 point value of chips based on electric range

A typical plug-in electric hybrid like the Prius Prime with 25 miles of range would get 0.9 credits, but the more capable Chevy Volt with 53 miles of range would net 1.3 credits. (Figure 2, above.)

A longer-range ZEV, such as the Chevy Bolt EV, will get 3.9 credits, and the 312-mile Toyota Mirai; 4.0 credits.

One might like to debate with CARB whether or not the Toyota Mirai really delivers three times the environmental benefit of the Chevy Volt, but who are we to argue with the creators of the game?

(Note: CARB uses the UDDS Test cycle to determine the vehicles' all-electric range but doesn't publicize the results. The EPA all-electric range is multiplied by about 1.4 to get the all-electric range used by CARB.)

Automakers who have figured out the rules are pulling ahead of others in the score.

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