Keeping plug-in electric vehicles connected to the grid - Patterns of vehicle use

In 2005 Kempton and Tomic laid out a vision for V2G which presumed that use of V2G technology could provide a high revenue stream to early plug-in electric vehicles, enabling market penetration of relatively high cost early-to-market electric drive vehicles. To assure access to the presumed revenue streams vehicles must be plugged in at a location which provides the V2G interconnect that enables the services to be provided to the grid. This presentation provides some background information relating to probability of being plugged in, by time and location. The more a vehicle is driven per day, the less time it will be parked. The more locations where the vehicle parks on a typical day, the greater the cost of provision of charge/discharge points to allow relatively continuous V2G services. Extension of parking time beyond time to charge the vehicle is desirable when possible. Time parked at a public charge point without charging represents a lost opportunity for other vehicles to charge at that point. For purposes of economic feasibility, the more hours per day a plug-in vehicle is driven, the greater the odds of a financial payback on the incremental cost of the vehicle. From the point of view of maximization of V2G revenues, the best vehicle is one always parked at the same location, where an easy and inexpensive link to the grid can be made and maintained for many hours per day. From the point of view of the purchaser of such vehicles, more hours of driving are better than less. Research on the location and duration of parking of different kinds of personal use vehicles conducted by the authors is reviewed for the benefit of those wishing to understand the likely behavior of owners of different types of vehicles, as well as the subset of high daily use vehicles most likely to be plug-in vehicles. Graphs and charts from prior publications are provided, with a list of references. The National Household Transportation Survey is used. Cars, minivans, SUVs and pickup trucks are examined. Vehicles used for work only, for work and other purposes, and not for work have been disaggregated. Regional and metropolitan vs. rural behavior is contrasted. Dwell times by destination type and hour of day have been examined. Least expensive residential V2G connections are first in new construction, then relatively new houses. Proximity of plugs and parking spots (lower costs of implementation) is generally greatest with off-street parking in a garage or carport. Data from the Annual Housing Survey has been analyzed to provide information on these patterns, regionally within the U.S.