(a) The rate of the tax under Sections 162.351 and 162.352 is 15 cents for each:
(1) gasoline gallon equivalent or fractional part of compressed natural gas or liquefied natural gas; or
(2) diesel gallon equivalent or fractional part of compressed natural gas or liquefied natural gas.
(b) The tax shall be imposed on an amount of compressed natural gas or liquefied natural gas equal to a:
(1) diesel gallon equivalent of compressed natural gas, as provided by § 162.001(19-a)(A), if the natural gas dispenser lists the price in diesel gallon equivalents and the natural gas is supplied to the dispenser from a pipeline or other nonliquefied source;
(2) diesel gallon equivalent of liquefied natural gas, as provided by § 162.001(19-a)(B), if the natural gas dispenser lists the price in diesel gallon equivalents and the natural gas is supplied to the dispenser from a liquefied source;
(3) gasoline gallon equivalent of compressed natural gas, as provided by § 162.001(29-a)(A), if the natural gas dispenser lists the price in gasoline gallon equivalents and the natural gas is supplied to the dispenser from a pipeline or other nonliquefied source; or
(4) gasoline gallon equivalent of liquefied natural gas, as provided by § 162.001(29-a)(B), if the natural gas dispenser lists the price in gasoline gallon equivalents and the natural gas is supplied to the dispenser from a liquefied source.