Buyers of plug-in hybrids such as the
California has capped the number of the Green Clean Air Vehicle decals that allow such cars into the lanes at 70,000. As of Monday, it had granted 66,255, leaving fewer than 4,000 left.
Those who already have the stickers – and those who nab the permits that are left - get carpool lane access until Jan. 1, 2019.
Plug-in hybrids are cars that have gasoline engines and electric drive systems that allow them to run only on electricity for varying distances.
The rechargeable Prius plug-in, for example, can operate on electricity for just 11 miles before switching into gas mode. The current Volt can travel about 38 miles on electricity. The redesigned Volt, which goes on sale later this year, will have an estimated 50-mile electric only range.
After the green decals run out, new car buyers looking to drive solo in carpool lanes will have to purchase vehicles that qualify for the white classification of decals. That's limited to 100% battery electric, hydrogen fuel cell and compressed natural gas vehicles. Those vehicles also get access until Jan. 1, 2019, and their numbers aren't capped.
Reaching the green decal limit spells trouble for sales of plug-in hybrids.
"Sales could fall of the cliff," said Jack Nerad, the executive market analyst with car information company Kelley Blue Book.
California has been their best market as buyers gravitated to the vehicles for their carpool lane access, he said.
Hitting the limit could drive up the value of the 70,000 vehicles that have or will qualify for the green stickers.
"It is a perk that has market value, and those vehicles will be in demand," Nerad said.
But there's also a good chance that the state legislature will authorize more green stickers, he said. The program was originally capped at just 40,000 vehicles and has already had two expansions.
"Allowing clean-air vehicles to access the carpool lane is a crucial component in the state's strategy to incentivize clean vehicles," Pavley said.
Such an expansion would be good news for Chevrolet, which needs the program to bolster sales of the new Volt it is about to launch.
"We know it is a significant consideration," said Michelle Malcho, a Chevrolet spokeswoman.
The automaker is supporting the bill.
But opposition is brewing.
The San Francisco Bay Area's Metropolitan Transportation Commission said that traffic congestion levels have risen almost 40% since 2010. It doesn't want to see more single-occupant vehicles allowed in carpool lanes.
"Carpool lanes are for carpools," said Randy Rentschler, the commission's director for legislation and public affairs. "We want to move people, not cars."
It could be time to change the permit rules so that only some plug-in hybrids – those with big enough batteries to travel longer distances only on electricity – are allowed into the lanes, said Don Anair, deputy director of the Clean Vehicles Program at the Union of Concerned Scientists.
A UC Davis study found that the Prius, with its short electric-only range, travels mostly powered by gasoline. Chevrolet Volt owners, however, drive far more miles in electric mode. Some studies have found that a majority of Volt miles are driven in electric mode.
"Obviously you have to balance the number of stickers to the functionality of the high occupancy vehicle lanes," Anair said.
The state should consider ways to differentiate the plug-in hybrids based on range, said Gil Tal, a professor at the UC Davis Institute of Transportation Studies. It should also plan incentives in a way that would the limit supply of permits to keep carpool lanes unclogged but still encourage sales of clean technology vehicles.
The state, he said, could offer permits that expire after a year or two, opening up space for a new plug-in buyer. Or it could give people a choice of obtaining a carpool lane permit or the $1,500 clean vehicle rebate the state pays to buyers of plug-in hybrids.
"For many people," Tal said, "the value of the sticker is higher than the $1,500 rebate."