Over the last century, the car has become the primary means of transportation for the developed world, as well as an icon of wealth and culture. Trillions of dollars were invested in the refueling infrastructure for cars, which now supplies about nine million barrels of gasoline per day to the U.S. alone (EIA, 2010). Today however, the auto industry is at the tipping point of the greatest transition it has ever experienced.
Still, the main barrier to electrification of the car industry is the electric car’s limited range. The fear of getting stranded on the side of the road with an empty battery, first observed in General Motor’s EV1-project is named: ‘Range Anxiety’ (Acello, 1997). Besides this barrier on the consumer’s side, electricity grid operators and independent researchers have expressed their concerns with the additional load from electric cars on the grid, especially during peak hours on hot summer days (IRC & KEMA, 2010), (PGE, 2009), (Papavasiliou, 2008). This study aims to provide insights into these issues by characterizing driving behavior in the United States using a dataset published by the Federal Highway Administration of the U.S. Department of Transportation. The hypothesis is that people overestimate the EV-range that they find necessary for their daily driven needs. All data and results are available from the website and can be used as a backbone for further research on range requirements and grid integration of electric vehicles.
In the first part of this study, a statistical analysis is conducted on the distances driven by the U.S. population. The results are projected on typical range bins seen in the portfolio of electric cars that are available as of 2011. The second part covers car usage patterns on an hourly basis for weekdays and weekends, which are in turn used to assess when cars are connected to the grid and available for charging. This may benefit Vehicle-to-Grid (V2G) studies and other Smart-Grid initiatives.
Part 1: Driving Range Requirements (on both National and State level)
Part 2: Usage Patterns for grid integration
Before the methodology and results are covered, some background around EV implementation phases is given, which will introduce the range bins used in the results. Then, a more detailed description is given on ‘Range Anxiety’, experienced by current and future EV-owners.
U.S. Energy Information Administration. (2010). Annual Petroleum & Other Liquids. July 28th, 2011. Retrieved from http://www.eia.gov/dnav/pet/pet_cons_psup_dc_nus_mbblpd_a.htm
IRC ISO/RTO Council, & KEMA. (2010). Assessment of Plug-in Electric Vehicle Integration with ISO / RTO Systems. Retrieved from http://www.isorto.org/atf/cf/%7B5B4E85C6-7EAC-40A0-8DC3-003829518EBD%7D/IRC_Report_Assessment_of_Plug-in_Electric_Vehicle_Integration_with_ISO-RTO_Systems_03232010.pdf
Pacific Gas and Electric Company. (2009). “The Perfect Storm for Electric Vehicle Market Growth in California” Smart Grid Workshop. California Public Utilities Commission Smart Grid Rulemaking. San Francisco.
Papavasiliou, A., Lee, A., Kaminsky, P., Sidhu, I., Tenderich, B., & Oren, S. (2008). Electric Power Supply and Distribution for Electric Vehicle Operations. Retrieved from http://cet.berkeley.edu/dl/EV2Grid_FinalREVISED.pdf