Solo carpool-lane access has proven to be one of the most effective tools to get California drivers to buy plug-in electric cars.

But soon new drivers of plug-in hybrids in the Golden State may no longer be able to take advantage of that perk--unlike new drivers of battery-electric cars.

The full allotment of 85,000 "green stickers" has been issued, and there will be no more unless the state legislature authorizes it.

DON'T MISS: Carpool-Lane Access: Very Important For Electric-Car Adoption, It Turns Out

If no such legislation is passed, the plug-in hybrid program will come to a halt as did the previous "yellow sticker" program for conventional hybrid cars, which was also limited to 85,000 stickers.

In the meantime, the California Department of Motor Vehicles will continue accept applications and put those owners on a waiting list, in case additional stickers are authorized.

The California Air Resources Board--which manages the state's green-car incentive programs--said the statutory limit for green carpool-lane stickers was reached on December 18.

2015 Chevrolet Volt

2015 Chevrolet Volt

Green stickers are used for conventional plug-in hybrids, as well as extended-range electric cars like the BMW i3 REx, Cadillac ELR, and first-generation Chevrolet Volt.

The total number of green stickers was originally capped at 40,000, but the limit was raised multiple times--most recently as part of state budget legislation passed earlier this year.

ALSO SEE: CA Green Stickers All But Gone; Q1's Plug-In Hybrid Sales Suffered This Year: UPDATE

Meanwhile, there are still an unlimited number of "white stickers" for available for battery-electric cars, hydrogen fuel-cell cars, and vehicles powered by compressed natural gas (CNG).

The carpool-lane exemption was originally set to expire this year, but legislation passed in late 2013 extended it to January 1, 2019.

2016 Volvo XC90 T8 Twin Engine plug-in hybrid

2016 Volvo XC90 T8 Twin Engine plug-in hybrid

All green and white stickers remain valid until then. The yellow stickers for hybrids expired on June 30, 2011, and are no longer valid.

Ironically, the green-sticker supply ran out roughly three months after the launch of the second-generation 2016 Chevy Volt, and just as several luxury plug-in hybrid SUVs are hitting showrooms.

MORE: 2016 Chevy Volt To Get California Carpool Lane Access

Those include the 2016 BMW X5 xDrive 40e, Mercedes-Benz GLE 550e, and Volvo XC90 T8 Twin Engine. An Audi Q7 plug-in hybrid is expected to follow them sometime next year.

None of those SUVs will likely see a green sticker, unless California officials decide to up the quota once again.

[hat tip: Benjamin]


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