Definitions under 42 U.S.C. § 6374(c) defines the following terms: acquired, alternative fuel, alternative fuel vehicle, dedicated vehicle, and heavy-duty vehicle.
For purposes of this part—
(1) the term "acquired" means leased for a period of sixty continuous days or more, or purchased;
(2) the term "alternative fuel" means methanol, denatured ethanol, and other alcohols; mixtures containing 85% or more (or such other percentage, but not less than 70% as determined by the Secretary, by rule, to provide for requirements relating to cold start, safety, or vehicle functions) by volume of methanol, denatured ethanol, and other alcohols with gasoline or other fuels; natural gas; liquefied petroleum gas; hydrogen; coal-derived liquid fuels; fuels (other than alcohol) derived from biological materials; electricity (including electricity from solar energy); and any other fuel the Secretary determines, by rule, is substantially not petroleum and would yield substantial energy security benefits and substantial environmental benefits;
(3) the term "alternative fueled vehicle" means a dedicated vehicle or a dual-fueled vehicle;
(4) the term "dedicated vehicle" means—
(A) a dedicated automobile, as such term is defined in section 32901 (a)(7)  of title 49; or
(B) a motor vehicle, other than an automobile, that operates solely on alternative fuel; (5) the term "dual-fueled vehicle" means—
(A) dual-fueled automobile, as such term is defined in section 32901 (a)(8)  of title 49; or
(B) a motor vehicle, other than an automobile, that is capable of operating on alternative fuel and is capable of operating on gasoline or diesel fuel; and
(5) the term "heavy-duty vehicle" means a vehicle of greater than 8,500 pounds gross vehicle weight rating.