Effects of Air Conditioner Use on Real-World Fuel Economy

Conference · Tue Jan 01 00:00:00 EST 2013

DOI:https://doi.org/10.4271/2013-01-0551· OSTI ID:1092236

Huff, Shean P ^[1]; West, Brian H ^[1]; Thomas, John F ^[1]

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1. ORNL

Vehicle data were acquired on-road and on a chassis dynamometer to assess fuel consumption under several steady cruise conditions and at idle. Data were gathered for various air conditioner (A/C) settings and with the A/C off and the windows open. Two vehicles were used in the comparisonstudy: a 2009 Ford Explorer and a 2009 Toyota Corolla. At steady speeds between 64.4 and 112.7 kph (40 and 70 mph), both vehicles consumed more fuel with the A/C on at maximum cooling load (compressor at 100% duty cycle) than when driving with the windows down. The Explorer maintained this trend beyond 112.7 kph (70 mph), while the Corolla fuel consumption with the windows down matched that of running the A/C at 120.7 kph (75 mph), and exceeded it at 128.7 kph (80 mph). The largest incremental fuel consumption rate penalty due to air conditioner use occurred was nearly constant with a weakslight trend of increasing consumption with increasing compressor (and vehicle) speed. Lower consumption is seenobserved at idle for both vehicles, likely due to the low compressor speed at this operating point

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Fuels, Engines and Emissions Research Center (FEERC)
• Sponsoring Organization: USDOE Office of Energy Efficiency and Renewable Energy (EERE)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1092236
• Resource Relation: Conference: SAE 2013 World Congress & Exhibition, Detroit, MI, USA, 20130416, 20130418
• Country of Publication: United States
• Language: English