Owners of plug-in hybrid electric vehicles (PHVs) often ignore meter information, according to a study from the University of Colorado’s Renewable and Sustainable Energy Institute (RASEI) in conjunction with NREL
The study, sponsored by Toyota, tracked 142 households with 265 drivers of PHVs. Xcel Energy installed smart plugs in study household garages. Participants could check a website to find vehicle power use when their cars were plugged in. They also were given the option of charging their cars at their convenience (unmanaged charging) or programming their cars to be charged during certain hours (managed charging).
Not surprisingly, those households paying standard electric rates preferred to charge whenever they wanted to and those with time-of-use (TOU) rates preferred the managed approach.
The study also found:
- Most households – about 90 percent – did not look at the website for feedback to manage their vehicle charging.
- Households tended to find managed charging inconvenient.
- To use managed charging, time-of-use households prefer a simple “set-it-and-forget-it” approach with easy override.
- While electricity pricing was the strongest influence on charging decisions, time/cost and convenience also were considered important.
- A majority of households were not satisfied with the driving range of their EV.