Evaluating the impact of Plug-in Hybrid Electric Vehicles on regional electricity supplies

Plug-in Hybrid Electric Vehicles (PHEVs) have the potential to increase the use of electricity to fuel the U.S. transportation needs. The effect of this additional demand on the electric system will depend on the amount and timing of the vehicles´ periodic recharging on the grid. We used the ORCED (Oak Ridge Competitive Electricity Dispatch) model to evaluate the impact of PHEVs on the Virginia-Carolinas (VACAR) electric grid in 2018. An inventory of one million PHEVs was used and charging was begun in early evening and later at night for comparison. Different connection power levels of 1.4 kW, 2 kW, and 6 kW were used. The results include the impact on capacity requirements, fuel types, generation technologies, and emissions. Cost information such as added cost of generation and cost savings versus use of gasoline were calculated. Preliminary results of the expansion of the study to all regions of the country are also presented. The results show distinct differences in fuels and generating technologies when charging times are changed. At low specific power and late in the evening, coal was the major fuel used, while charging more heavily during peak times led to more use of combustion turbines and combined cycle plants.