BEVs (battery electric vehicles) and PHEVs (plug-in hybrid electric vehicles) show significant performances in MPG (miles per gallon of gasoline) equivalent and energy savings.
Among new car models for 2018, a BEV has a maximum MPGe of 136 and minimum annual energy cost of US$500 in terms of fuel economy, followed by a PHEV with a maximum MPGe of 133 and minimum annual energy cost of US$600, Digitimes Research have found.
Previous hybrid electric vehicles (HEVs) were of series, parallel and series-parallel types of driving systems, with MPG mostly exceeding 47 and average annual energy cost of about US$700. However, HEVs' batteries are recharged by internal combustion engines, or replaced when electricity is depleted. And HEVs discharge quite high volumes of carbon dioxide.
BEVs and PHEVs have been developed to solve such problems. Some automakers have launched range-extended electric vehicles (REEVs) and fuel cell EVs to increase total running distance at full storage or electricity, but such models are inferior to BEVs and PHEVs in energy savings.