7:00am: alarm sounds; breakfast; get dressed
7:30am: unplug my plug-in hybrid vehicle and go to work
5:00pm: leave work
5:30pm: arrive home and recharge my plug-in hybrid vehicle
The kind of pressure plug-in vehicles (PHEVs) will place on our electricity grid has been under scrutiny for some time. Initially, this product seems to offer an all-around alternative to conventional vehicles. In theory, a low emissions technology that will not need much from the already existing electricity grid since the infrastructure is ready to support recharging during off-peak hours.
However, are we sure the fifty million PHEV 2030 forecasted owners will recharge their vehicle during off-peak hours?
In an article published by The Electricity Journal, Hadley and Tsvetkova present an analysis that shows the impact PHEV penetration can have in our electric grid. 
Taking into consideration type of connection to grid as well as capacity of the vehicle’s battery, different charging behaviors are modeled and their potential impact on the grid analyzed. The figure below shows the Base Load, or expected load to be generated by the utilities to satisfy electricity demands, and the additional load added by the PHEV recharging. For example, the 6 kW Evng scenario represents a PHEV being charged via a 240 volt and 30 amp circuit during the early evening. This particular example would be expected to raise the base peak load.
The results of the scenario where PHEV owners recharge their vehicle after work, versus during off-peak hours are as follows:
– Increase in Electrical Demand due to PHEVs in 2030: 3%
– Increase in Capacity Demanded due to PHEVs in 2030: between 130GW
– Increase in wholesale electricity prices: 40%
It will be a challenge to change our habits.