(a) A political subdivision may not adopt or enforce an ordinance, order, regulation, or similar measure that directly prohibits or restricts the use, sale, or lease of an engine based on its fuel source.
(b) This section does not limit the authority of a political subdivision to adopt or enforce an ordinance, order, regulation, or similar measure not preempted by state or federal law that:
(1) does not effectively prohibit or restrict the use, sale, or lease of the engine;
(2) implements an agreement between the political subdivision and the Texas Commission on Environmental Quality to regulate motor vehicle idling under § 382.019, Health and Safety Code; or
(3) only affects an engine owned or operated by the political subdivision and is included in the state implementation plan or otherwise necessary for compliance with the federal Clean Air Act (42 U.S.C. § 7401 et seq.).

(c) This section does not limit the authority of a political subdivision to adopt an ordinance, order, regulation, resolution, policy, or other similar measure to encourage, promote, or provide rebates for engines and fuel sources from alternative sources such as electricity, hydrogen, gas, or biofuels and that does not directly or effectively ban, restrict, or prohibit the use, sale, or lease of an engine based on the engine’s fuel source.
(d) § 81.0523, Natural Resources Code, prevails to the extent of a conflict with this section.

(a) A political subdivision may not adopt or enforce an ordinance, order, regulation, or similar measure that directly prohibits or restricts the use, sale, or lease of an engine based on its fuel source.
(b) This section does not limit the authority of a political subdivision to adopt or enforce an ordinance, order, regulation, or similar measure not preempted by state or federal law that:
(1) does not effectively prohibit or restrict the use, sale, or lease of the engine;
(2) implements an agreement between the political subdivision and the Texas Commission on Environmental Quality to regulate motor vehicle idling under § 382.019, Health and Safety Code; or
(3) only affects an engine owned or operated by the political subdivision and is included in the state implementation plan or otherwise necessary for compliance with the federal Clean Air Act (42 U.S.C. § 7401 et seq.).

(c) This section does not limit the authority of a political subdivision to adopt an ordinance, order, regulation, resolution, policy, or other similar measure to encourage, promote, or provide rebates for engines and fuel sources from alternative sources such as electricity, hydrogen, gas, or biofuels and that does not directly or effectively ban, restrict, or prohibit the use, sale, or lease of an engine based on the engine’s fuel source.
(d) § 81.0523, Natural Resources Code, prevails to the extent of a conflict with this section.