摘要：An increasingly diverse set of hybrid-electric vehicles (HEVs) is now available in North
America. The recent generation of HEVs have higher fuel consumption, are heavier, and
are significantly more powerful than the first generation of HEVs. We compare HEVs for
sale in the United States in 2007 to equivalent conventional vehicles and determine how
vehicle weight and system power affects fuel consumption within each vehicle set. We find
that heavier and more powerful hybrid-electric vehicles are eroding the fuel consumption
benefit of this technology. Nonetheless, the weight penalty for fuel consumption in HEVs is
significantly lower than in equivalent conventional internal combustion engine
vehicles (ICEVs). A 100 kg change in vehicle weight increases fuel consumption by
0.7 l/100 km in ICEVs
compared with 0.4 l/100 km in HEVs. When the HEVs are compared with their ICEV counterparts in an equivalence model that
differentiates between cars and sports-utility vehicles, the average fuel consumption benefit was
2.7 l/100 km. This analysis further reveals that a HEV which is 100 kg heavier
than an identical ICEV would have a fuel consumption penalty of
0.15 l/100 km. Likewise, an increase in the HEV's power by 10 kW results in a fuel consumption penalty of
0.27 l/100 km.
