PHOENIX, AZ – Maricopa County’s entire diesel fleet now runs on biodiesel, a blend of traditional diesel fuel and biodegradable material, according to the Arizona Republic newspaper. The change happened this summer, when, by July, all 629 of the county’s diesel vehicles were running on the new fuel. More than 40 percent of the county’s entire fleet now runs on alternative fuels, including propane, natural gas, and hybrid vehicles.

The cost to the county was minimal, according to said John Cantu, director of the county equipment services department. Diesel vehicles don’t need any upgrades or re- engineering to run on biodiesel. To avoid any potential maintenance problems, the county slowly phased in organic material until the fuel reached a proportion of 80 percent petroleum diesel and 20 percent biological material. Vehicle operators haven’t reported any mechanical problems since the fuel was introduced, according to the Arizona Republic.

The Arizona Climate Change Advisory Group, which advises Gov. Janet Napolitano, also recommended that the state replace its entire fleet with alternative fuel, hybrid, or low-emitting vehicles, as part of a larger goal of reducing greenhouse gas emissions.