Dive Brief:
- Newly released data from behavioral efficiency software-as-a-service provider Opower shows that electric vehicle owners with rooftop solar systems use the least amount of central grid electricity.
- Over a 24-hour period, electric vehicle owners use about 25 kilowatt-hours of electricity on average while other households use about 15 kilowatt-hours. However, electric vehicle and rooftop solar owners use slightly less utility power than the normal household average.
- 32% of electric vehicle owners surveyed have rooftop solar installed, according to Opower.
![](http://blog.opower.com/wp-content/uploads/2014/06/COM-174-Image-6-140620.png)
Dive Insight:
Opower revealed that electric vehicle users tend to have time-variable rate plans where the utility provides discounted power at night and more expensive power during the daily peak period. This has skewed electric vehicle owners' nighttime electricity use to about three times that of the average household.
The study also found that electric car owners, by virtue of their likelihood to have larger and more appliance-rich homes than the average customer, tend to use more electricity on average than their counterparts.
Offering a time-variable rate makes sense for electric vehicle owners: If they charged their cars during peak periods, such as the evening, the high demand on the grid would likely cause less reliable supply of electricity for all.
![](http://blog.opower.com/wp-content/uploads/2014/06/COM-174-Image-2-1406261.png)