((a)) ** Definitions** In this section:

((1)) ** Fuel cell electric vehicle** The term “fuel cell electric vehicle” means an on-road or non-road vehicle that uses a fuel cell (as defined in ).section 16152 of this title

((2)) ** Hybrid electric vehicle** The term “hybrid electric vehicle” means a new qualified hybrid motor vehicle (as defined in ).section 30B(d)(3) of title 26

((3)) ** Medium- or heavy-duty electric vehicle** The term “medium- or heavy-duty electric vehicle” means an electric, hybrid electric, or plug-in hybrid electric vehicle with a gross vehicle weight of more than 8,501 pounds.

((4)) ** Neighborhood electric vehicle** The term “neighborhood electric vehicle” means a 4-wheeled on-road or nonroad vehicle that—

((A)) has a top attainable speed in 1 mile of more than 20 mph and not more than 25 mph on a paved level surface; and

((B)) is propelled by an electric motor and on-board, rechargeable energy storage system that is rechargeable using an off-board source of electricity.

((5)) ** Plug-in electric drive vehicle** The term “plug-in electric drive vehicle” means a vehicle that—

((A)) draws motive power from a battery with a capacity of at least 4 kilowatt-hours;

((B)) can be recharged from an external source of electricity for motive power; and

((C)) is a light-, medium-, or heavy duty motor vehicle or nonroad vehicle (as those terms are defined in ).

((b)) ** In general**

((1)) ** Allocation** The Secretary shall allocate a credit to a fleet or covered person that is required to acquire an alternative fueled vehicle under this subchapter, if that fleet or person acquires an alternative fueled vehicle in excess of the number that fleet or person is required to acquire under this subchapter or acquires an alternative fueled vehicle before the date that fleet or person is required to acquire an alternative fueled vehicle under such subchapter.

((2)) ** Electric vehicles** Not later than , the Secretary shall—

((A)) allocate credit in an amount to be determined by the Secretary for—

((i)) acquisition of—

((I)) a hybrid electric vehicle;

((II)) a plug-in electric drive vehicle;

((III)) a fuel cell electric vehicle;

((IV)) a neighborhood electric vehicle; or

((V)) a medium- or heavy-duty electric vehicle; and

((ii)) investment in qualified alternative fuel infrastructure or nonroad equipment, as determined by the Secretary; and

((B)) allocate more than 1, but not to exceed 5, credits for investment in an emerging technology relating to any vehicle described in subparagraph (A) to encourage—

((i)) a reduction in petroleum demand;

((ii)) technological advancement; and

((iii)) a reduction in vehicle emissions.

((c)) ** Allocation** In allocating credits under subsection (b), the Secretary shall allocate one credit for each alternative fueled vehicle the fleet or covered person acquires that exceeds the number of alternative fueled vehicles that fleet or person is required to acquire under this subchapter or that is acquired before the date that fleet or person is required to acquire an alternative fueled vehicle under such subchapter. In the event that a vehicle is acquired before the date otherwise required, the Secretary shall allocate one credit per vehicle for each year the vehicle is acquired before the required date. The credit shall be allocated for the same type vehicle as the excess vehicle or earlier acquired vehicle.

((d)) ** Use of credits** At the request of a fleet or covered person allocated a credit under this section, the Secretary shall treat the credit as the acquisition of one alternative fueled vehicle of the type for which the credit is allocated in the year designated by that fleet or person when determining whether that fleet or person has complied with this subchapter in the year designated. A credit may be counted toward compliance for only one year.

((e)) ** Transferability** A fleet or covered person allocated a credit under this section or to whom a credit is transferred under this section, may transfer freely the credit to another fleet or person who is required to comply with this subchapter. At the request of the fleet or person to whom a credit is transferred, the Secretary shall treat the transferred credit as the acquisition of one alternative fueled vehicle of the type for which the credit is allocated in the year designated by the fleet or person to whom the credit is transferred when determining whether that fleet or person has complied with this subchapter in the year designated. A transferred credit may be counted toward compliance for only one year. In the case of the alternative fuel provider program under , a transferred credit may be counted toward compliance only if the requirement of is met.section 13251 of this titlesection 13251(a)(4) of this title

((f)) ** Authorization of appropriations** There are authorized to be appropriated such sums as are necessary to carry out this section for each of fiscal years 2008 through 2013.