An Analysis of Car and SUV Daytime Parking for Potential Opportunity Charging of Plug-in Electric Powertrains

Using the 2009 National Household Transportation Survey (NHTS), an analysis of opportunity charging potential during daytime, for the time interval when a car or SUV is parked for the longest duration, is presented here. We focus on charging at 3.3 kW or less, either using the charger at the dwelling unit a second time per day (a one charger solution), or using a second charge point at work. Our earlier research with the 2009 NHTS indicates that nearly 60% of vehicles within this sample were driven to work, or returned to home between 6:00 AM and 6:00 PM. In this analysis we consider the potential for daytime charging before summertime afternoon utility load peaks, anticipating that Public Utility Commissions (PUCs) supporting smart grid pricing strategies may impose much higher electricity costs at these times. We consider kW ratings of typical opportunity chargers versus overnight chargers. We consider the plug-in hybrid with 28 km of urban electric range (PHEV28), the extended range electric vehicle with 56 km of universal all-electric operation capability (EREV56) and the battery electric vehicle with 117 km of electric range (BEV117). Electricity demand and gasoline fueled miles reduction is examined for the average circumstance in two daily distance brackets (48-80 km, 80-160 km) and for two charging behaviors – (1) overnight and (2) both overnight and during the longest duration parking event of daytime hours, from 6 am to 6 pm.