One of the major incentives for buying a plug-in electric car in California is the coveted sticker allowing single-occupant travel in the carpool lanes on the state's crowded freeways.

Now, the supply of stickers for plug-in hybrids that can travel on battery power alone but also have an engine as backup is close to running out.

2012 Toyota Prius Plug-In Hybrid - production model

2012 Toyota Prius Plug-In Hybrid - production model

The green stickers are capped at 40,000, and the California Air Resources Board provides updated reports on how many have been issued.

Here's are three tallies over the course of last year:

  • 'As of December 31, 2013, 28,739 "green" stickers have been issued.'
    'As of November 8, 2013, 24,452 "green" stickers have been issued'
    'As of March 1, 2013, almost 10,900 "green" stickers have been issued'

Totally zero-emission vehicles--battery electrics and hydrogen fuel-cell vehicles--and natural-gas cars are issued white stickers, of which there is currently an unlimited supply.

The pace of green-sticker issuance increased at the end of last year, as more models came on the market and awareness of the upcoming limit grew.

Over seven months ending in early November, about 13,500 stickers were issued--a rate of less than 2,000 a month--bringing the total to 24,452.

Graph of CARB HOV-Lane Access green stickers issued through Dec 31, 2013, w/projection thru May 2014

Graph of CARB HOV-Lane Access green stickers issued through Dec 31, 2013, w/projection thru May 2014

Then the rate increased, with almost 4,300 additional green stickers issued in less than eight weeks, taking the total to 28,739 by December 31.

So if we do some simple graphing, we can plot for two alternatives: the historic rate since March, or the new, more accelerated rate from the last two months of the year.

At the historic rate, stickers hit 40,000 around mid-May--but if the new, faster rate is adopted, they run out considerably earlier, perhaps as soon as sometime next month.

In either scenario, if you're thinking of buying a Chevrolet Volt, Cadillac ELR, or one of the five plug-in hybrid models offered by Ford, Honda, Porsche, or Toyota, you'll be out of luck for those carpool lane--unless you buy the car and apply for a green sticker this month or next.

One possibility, of course, is that new legislative action could increase the supply of green stickers sometime after they run out early this year.

Either way, you have been warned.


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