California's rules requiring six automakers to sell specified numbers of zero-emission vehicles starting in 2012 have had a substantial impact.

But a meeting to be held one week from today may determine whether required volumes of emission-free cars--likely battery-electric vehicles--are cut for a second group of automakers.

The California Air Resources Board (CARB) will hold a hearing on proposed changes to its 2012 zero-emission vehicle (ZEV) mandate for what are called Intermediate Vehicle Makers:

DON'T MISS: CA To Require Zero-Emission Vehicles On Top Of Gas-Mileage Rules (Dec 2011)

Why pay attention to arcane changes in a single state's rules? Largely because it will affect how many battery-electric cars are offered three to five years hence.

2014 Chevrolet Spark EV - First Drive, Portland, July 2013

2014 Chevrolet Spark EV - First Drive, Portland, July 2013

While the Nissan Leaf electric car sells in high volume, five other automakers have been pushed into offering at least small numbers of so-called compliance cars.

Those cars--the Chevrolet Spark EV, Fiat 500e, Honda Fit EV, Toyota RAV4 EV, and arguably the Ford Focus Electric as well--have given their makers experience with the nuts and bolts of building and selling battery-electric vehicles.

Large vs intermediate makers

Those six makers are known as the Large Vehicle Makers, because they are the six highest-selling car companies in the state of California.

While CARB fixed the volumes of zero-emission vehicles at the same level from 2012 through 2017, the numbers start to rise sharply from 2018 through 2025.

More importantly, the new group of intermediate vehicle makers (IVMs) has to sell ZEVs for the first time.

Land Rover Range_e diesel plug-in hybrid

Land Rover Range_e diesel plug-in hybrid

The changes proposed by the agency follow roughly two years of discussion between CARB staff and the affected automakers, who include Jaguar Land Rover, Mazda, Mitsubishi, Subaru, and Volvo.

[EDITOR'S NOTE: An earlier version of this article incorrectly stated that Hyundai-Kia was part of the IVM group; it is not. We regret the error.]

Plug-in hybrids rather than electric cars

The intermediate makers have argued essentially that their smaller size and more limited resources make developing battery-electric vehicles much harder.

While they could also purchase ZEV credits--from Tesla Motors, which has no emitting vehicles to offset, or perhaps from Nissan--it's not clear that this would allow them to meet the full requirements for 2018 through 2025.

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Broadly, the proposed modifications let the IVMs meet their requirements using Transitional Zero-Emission Vehicles (TZEVs) rather than pure ZEVs.

What CARB calls TZEVs are better known to consumers as plug-in hybrids.

Mitsubishi Outlander PHEV Concept-S, 2014 Paris Auto Show

Mitsubishi Outlander PHEV Concept-S, 2014 Paris Auto Show

Plug-in hybrid SUVs coming

While only Mitsubishi now has a plug-in hybrid on the market--its long-delayed Outlander Plug-In Hybrid mid-size SUV--Jaguar Land Rover has announced it will offer plug-in hybrid powertrains in two of its Range Rover SUVs as well.

Volvo, too, has a plug-in hybrid wagon on the market in Europe and will soon offer its new 2016 XC90 large SUV with a T8 Twin Engine plug-in hybrid option.

That leaves Mazda and Subaru as the two makers with no known plug-in hybrid vehicles on the horizon.

2015 Nissan Leaf

2015 Nissan Leaf

The changes also somewhat reduce the numbers of overall vehicles required, although apparently next week's hearing will include discussion of where the final numbers should fall.

If the proposed changes are adopted, it appears that the required TZEV volumes may not be appreciably higher than current "compliance car" volumes of battery-electric vehicles.

And the changes would also appear to length the time toward CARB's original goal of giving manufacturers early experience with zero-emission vehicles to make higher production volumes easier in later years.

2015 Ford Focus Electric

2015 Ford Focus Electric

Large makers: ZEV volumes rise

Meanwhile, the existing regulations for the large makers--Fiat Chrysler, Ford, General Motors, Honda, Nissan, and Toyota--will require them to sell increasing volumes of zero-emission vehicles starting in 2018.

For their part, both Honda and Toyota will likely meet those levels with small numbers of hydrogen fuel-cell vehicles.

GM and Nissan will sell electric cars, and it remains unclear what strategy Fiat Chrysler and Ford will adopt.

The hearing will be held on Thursday, October 23, at 9 am Pacific time in the auditorium of the South Coast Air Quality Management District in Diamond Bar, California.


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