California Code, Public Resources Code - PRC § 26054

(a) A voluntary contractual assessment on property authorized pursuant to paragraph (2) of subdivision (a) of Section 5898.20 of the Streets and Highways Code.

(b) A voluntary contractual assessment or a voluntary special tax on property to finance the installation of distributed generation renewable energy sources, electric vehicle charging infrastructure, or energy or water efficiency improvements that is levied pursuant to a chartered city's constitutional authority under Section 5 of Article XI of the California Constitution.

(c) A special tax on property authorized pursuant to subdivision (b) of Section 53328.1 of the Government Code.