California Code, Health and Safety Code - HSC § 41062

(a) The strategy shall include a clean fuels program to provide, to the extent feasible and necessary to carry out the purposes of this chapter, a schedule for the introduction of cleaner burning alternative fuels and low-emission motor vehicles or control measures providing equivalent emission reductions within the district, a program to encourage the establishment of the necessary infrastructure to support the introduction of cleaner burning fuels, and demonstration programs and incentives to encourage the purchase of clean fueled vehicles and the use of cleaner burning fuels.

(b) In developing the clean fuels program, the district shall consider projects utilizing methanol fuel; fuel cells; liquid petroleum gas; natural gas, including compressed natural gas; combination fuels; synthetic fuels; electricity, including electric vehicles; ethanol; and other cleaner burning fuels.

(c) Nothing in this section authorizes the Sacramento district to require the sale or supply of any specific motor vehicle fuel.