PHOENIX-Going green has helped Maricopa County save an estimated $2.7 million in energy costs alone, according to the Arizona Republic.

Green efforts include:

Switching to biodiesel fuel for county vehicles. The County has diverted more than 300 metric tons of greenhouse-gas emissions, according to a recent report.

Preferred parking. Four county locations have set aside special parking spaces for hybrid or alternative-fuel vehicles.

Public transportation. Nearly half the county's 13,000 employees now receive subsidized bus and light-rail passes; all county employees are eligible.

Cleaner cars. The Environmental Services Department will replace half its fleet of 113 cars with alternative-fuel or hybrid vehicles by 2012.

Reducing dust. The county transportation agency will allocate $3 million each year to pave dirt roads and roadway shoulders to reduce dust emissions.