First, as to the question about out-of-state visitors in green vehicles being allowed to use HOV lanes, the answer is that no state could pass and enforce a law that restricted access to roads or availability of lanes to state residents only. To do so, a state would probably have to relinquish any claim to federal highway funding (which would be a substantial loss of matching funds). This is especially true of HOV lanes in Nevada, which are almost exclusively available on interstate highways (I-15 in southern Nevada, for example).
Secondly, while it’s true that the Nevada Legislature passed a law (AB 511, 2011) that allows electric and hybrid vehicles to use HOV lanes regardless of the number of passengers in the car, the bill also specifically states that the Department of Transportation must first formulate the policy.
Here’s the specific wording from AB 511: "Section 10 of this bill authorizes the use of a qualified alternative-fuel vehicle in high-occupancy vehicle lanes irrespective of the occupancy of the vehicle, if the Department of Transportation has adopted the necessary regulations" [emphasis added].
So, has the DOT adopted the necessary regulations?
According to the 2013 Executive Summary of the Southwest Energy Efficiency Project (SWEEP), "No progras has been set up as of March 15, 2013."
According to PlugIncentives.com, as of September 2014, Nevada did not allow electric or hybrid vehicles unlimited access to HOV lanes.
Finally, according to the Nevada Electric Vehicle Accelerator (NEVA), "Plans by the NDOT are to phase in the electric-vehicle [HOV-lane exemption] after construction upgrades around the state, including Project NEON* in southern Nevada."
Tony Illia, public information officer for the Department of Transportation in southern Nevada, concurs. "The Nevada Legislature has passed the law, but the Department of Transportation hasn’t inaugurated the program."
For anyone who missed yesterday's QoD, Project NEON is a $1.5 billion upgrade of a 3.7-mile stretch of I-15 from the Spaghetti Bowl to the Sahara Avenue exit; construction is scheduled to begin sometime in 2016 and take a little more than two years.
Thus, it looks like the HOV exemption for electric and hybrid vehicles is at least three years down the road (pun intended).