In Colorado, I'm seeing this. C.R.S. 42-3-304.
25 C I refers to the federal law which states
The term “motor vehicle†means any vehicle which is manufactured primarily for use on public streets, roads, and highways (not including a vehicle operated exclusively on a rail or rails) and which has at least 4 wheels. But then 25 c II makes it sound like it
would actually include motorcycles. Colorado "only" charges $50 right now, at least.
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(25) (a) Beginning January 1, 2014, in addition to any other fee imposed by this section, county clerks and recorders shall annually collect a fee of fifty dollars at the time of registration on every plug-in electric motor vehicle. County clerks and recorders shall transmit the fee to the state treasurer, who shall credit thirty dollars of each fee to the highway users tax fund created in section 43-4-201, C.R.S., and twenty dollars of each fee to the electric vehicle grant fund created in section 24-38.5-103, C.R.S.
(b) The department of revenue shall create an electric vehicle decal, which a county clerk and recorder shall give to each person who pays the fee charged under paragraph (a) of this subsection (25). The decal must be attached to the upper right-hand corner of the front windshield on the motor vehicle for which it was issued. If there is a change of vehicle ownership, the decal is transferable to the new owner.
(c) As used in this section, "plug-in electric motor vehicle" means:
(I) A motor vehicle that has received an acknowledgment of certification from the federal internal revenue service that the vehicle qualifies for the plug-in electric drive vehicle credit set forth in 26 U.S.C. sec. 30D
https://www.law.cornell.edu/uscode/text/26/30D, or any successor section; or
(II) Any motor vehicle that can be recharged from any external source of electricity and the electricity stored in a rechargeable battery pack propels or contributes to propel the vehicle's drive wheels.
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