5 Million Gallons Save in One YearState governments in the US operate large vehicle fleets, and California has a huge one. Just in one year, in 2003, the state fleet burned 38,559,715 gallons of fuel (gasoline and diesel combined). The silver lining is that these large fleets allow governments to preach by example and use their purchasing power to support fuel-efficient technologies. And with oil prices expected to keep rising over time, burning less of the stuff should be good for taxpayers too.
It looks like they've surpassed the 2012 goal, and are on their way to reach the 2020 goal:
In 2003, the state fleet consumed 38,559,715 gallons of petroleum-based fuel (gasoline and diesel), according to the report. In 2010, the fleet consumed 33,509,180 gallons of petroleum fuel (-13%) as well as 3,793,904 gallon of alternative fuels, comprising:
3,253,548 gallons of biodiesel (86%)
281,619 gallons gasoline equivalent (gge) of CNG and propane (7%)
216,723 gallons E85 ethanol (6%)
42,014 gge of electricity (1%)
But to me it seems like the 2020 goal is not ambitious enough. Just normal improvements in fuel economy should easily allow them to reach that goal. They should aim much higher! In 8 years, they should have the time to do much better compared to the 2003 baseline by having more of their passengers cars be at least hybrids, if not plug-in hybrids or fully electric cars, and bigger vehicles (trucks, big vans) could also run much more cleanly by using things like biodiesel, CNG (carbon neutral biogas if available), hydraulic or flywheel hybrids, etc.