Electric vehicles charging at Coca-Cola's Atlanta headquarters.
As electric vehicle adoption continues to grow, carmakers and government agencies are increasing their support of public EV charging infrastructure. While much of the attention is focused on public charging—especially fast charging along highway corridors—the importance of workplace charging is also on the rise. Considering that employees often park their car for long periods, workplace charging can be one of the most useful and cost-effective ways to encourage electric car adoption.
In January 2013, the US Department of Energy announced 13 major US employers and eight stakeholder groups had joined the new “Workplace Charging Challenge” to help expand access to workplace charging stations for American workers across the country. By January 2017, more than 400 employers had joined as partners, resulting in 750 workplaces with over 7,500 charging stations accessible to nearly one million employees.
Logically, car companies like General Motors took an early lead. GM now has more than 500 workplace charging stations across the country, including 357 in Michigan, 53 in New York, and 24 in California. In the eight or so year since beginning to install charging stations, General Motors learned that low-cost Level 1 charging was just as important as Level 2 240-volt charging.
Level 2 charging can add 20 to 25 miles of range in an hour—compared to Level 1’s so-called trickle-charge that adds about four miles in an hour. But GM discovered that installing Level 2 represented on average about $10,000 in cost per charge spot, while Level 1 cost only about $1,000 on average.
The faster charge was enjoyed by EV drivers, but many of them found it inconvenient to unplug and move their electric car or plug-in hybrid in the middle of the day. When the charging spots are occupied by fully charged cars, the infrastructure was not being fully utilized. Meanwhile, plugging a car in for an eight-hour workday in a less expensive Level 1 location could add 30 or more miles of range—which is helpful for many local commuters.
Coca-Cola, which has about 100 charging stations at its Atlanta Headquarters, installed a smart mix of charging levels—about 80 percent of which are Level 1. The company has the single largest EV charging site in Georgia.
The company’s goals were to allow EV commuters to add only about half their battery capacity during the day. Perhaps more importantly, Coca-Cola required employees to allow their co-workers to unplug cars that were fully charged or otherwise did not need the charge. EV-driving employees at Coca-Cola can communicate with one another via an internal chat service. The company also experimented with shifts and alternative-day scheduling, so that an employee is only allowed to use the charging spot on specified days or hours.
Coca-Cola found that it’s better to be slightly behind demand—adding EV chargers as you need them rather than installing stations that are seldom used. Networked charging stations with payment systems were often not warranted.
These lessons will be key to employers just beginning to add workplace charging. To support these efforts in New York City, CALSTART, an organization dedicated to supporting clean transportation, in April announced “Charge to Work.” The program will include a three-year marketing and outreach campaign to engage more than 100 businesses to encourage employees to adopt EVs.
Also in April, The San Diego-based Center for Sustainable Energy announced that it will help California manage a $200 million program to dramatically increase the number of electric vehicle charging stations. “This really changes the landscape of electric vehicle charging in California,” said Colin Santulli, director of clean transportation for the Center for Sustainable Energy. He also noted that while most EV owners charge their vehicles primarily at home, the need for workplace charging is critical.