In 2009 the DOE launched the EV Project, which will direct $230 million of public and private funds to “study methods to effectively deploy charging infrastructure in support of plug-in electric vehicles.” For the past two years, the under-publicized EV Project has collected data covering EV driving patterns and charging infrastructure utilization. In early March, EV Project managers Ecotality and the Idaho National Laboratory invited industry participants to discuss the project so far and suggest improvements in how the information can be recorded and disseminated.
During the day-long peer review meeting, run by EV Project managers, we reviewed the latest (Q4 2012) data, which contains very useful information about how much charging infrastructure is needed. Surprisingly, although several auto makers – who have much to gain from a robust charging infrastructure – were invited, none attended.
The bad news for companies hosting public EV charging locations is that the equipment is not being used very often. On average, the Level 1 or 2 AC charging stations enrolled in the EV Project were accessed only once every five days during the fourth quarter of 2012. While that utilization rate should improve as more plug-in vehicles are sold, it is nearly impossible to build a business case when the equipment is idled nearly all of the time. Data from the EV Project will help manufacturers and installers understand where chargers should be located within an area, and how many stations are needed per vehicle.
The few (54) DC fast chargers installed fared much better, with 1.6 visits per day. One significant finding from the project could lead to lower-powered DC fast chargers. The CHAdeMO charging equipment being used can deliver up to 50 kilowatts of power depending on the battery’s state of charge, but the report showed that the average power delivered was only 22 kW. This is because the chargers will reduce the power rate as the battery pack gets closer to full, to prevent overcharging, and many customers kept the vehicle plugged in after charging had slowed for some time.
If EV drivers on average spend enough time at a charging station for lower power equipment (20-25 kW) to meet their needs, then less expensive equipment could be installed. Many EVSE suppliers are now offering lower power DC fast chargers, including most recently ABB and Fuji. Developments in DC fast charging will be discussed during Navigant Research’s upcoming free webinar.
The afternoon sessions of the EV Project review were dedicated to more granular data to better inform industry players and consumers. Do PEV drivers tend to use charging infrastructure more or less frequently over time? How many times per day do vehicles in a specific region charge at public locations?
Companies need to make decisions about how many vehicles to produce and charging stations to deploy. The EV Project data provides a good foundation, but so far it has yet to make an impact on decision makers. Hopefully that will change soon.