(a) The Commissioner of Revenue Services, in consultation with the Commissioner of Energy and Environmental Protection, shall, on or before June 15, 2014, and on or before each June fifteenth thereafter, issue information concerning the computation of tax on motor vehicle fuels occurring in gaseous form. Such information shall include the conversion factor to be used to determine the liquid gallon equivalent of motor vehicle fuels in a gaseous form. Such conversion factor shall be consistent with the applicable federal standard, and shall be applicable for the twelve-month period beginning on the succeeding July first.
(b) The provisions of this section shall apply to propane only if such propane is used exclusively in motor vehicles owned by the purchaser of such propane and provided such propane is stored in a cylinder or tank owned by the purchaser. For purposes of this section, “propane” means a gaseous paraffin hydrocarbon that becomes liquid under pressure or reduced temperatures.