City of Chicago

Matt StewartReducing Idling in the City Fleet

Idle-reduction Human Factors

Idling is almost entirely human choice, even after modifying vehicles for engine-off operation

• 2006 policy– Five-minute limit for all city vehicles

• 2010 municipal ordinance– Three-minute limit for all on-road, diesel-

powered vehicles

• Stickers, keychains, etc.• Eco-driving training

Idle-reduction Technology

• Hybrid vehicles– Eliminating idling more important than

propulsion efficiency

• Heaters– Coolant heaters– Air heaters

• Five-minute idle-shutdown timers– Aftermarket timers on MD/HD trucks– Factory shutdown option

Tracking Idling

• Fuel usage– Compare change in fuel consumption over

successive years while controlling other variables– Timed coolant heaters: 12.6% difference in GPM

change from one winter to the next versus trucks without heaters, saving 25,000 fuel gallons

• GPS data– Millions of records; system not designed for this– Argonne team has been able to find some impact

of idle-reduction efforts