Last week’s localized power outage meant the White electric express bus could only charge at the Kimball Junction Transit Center—not at the other end of its route at the Old Town hub. The City is looking to reduce carbon emissions by switching to an all-electric fleet. But what happens if the power goes out?
Park City Transportation Planning Manager Alfred Knotts says the City recognizes that risk and has contingency plans in place for an outage or grid failure. In addition to the quick-charging stations at Old Town and Kimball Junction, Knotts says new chargers—similar to the ones used for personal electric vehicles—power the City’s most recent additions to the fleet.
“So we just received seven new electric buses and those have overnight charging capabilities that allow them to pretty much run their routes throughout the whole day on one charge," Knotts said. "Now, they will hit the fast chargers every once in a while to keep them at a certain level, but that is the infrastructure that we're planning for, and building and providing.”
Knotts says the electric buses can go about 250 miles on a full battery, though a few factors impact the range. Cold weather drains the battery faster, as well as driving uphill, and even the driver’s acceleration and braking habits affect the charge.
Knotts says the Transit team will soon present a fleet conversion policy to the City Council, outlining a plan to maintain the level of transportation service as the fleet transitions. Part of that is the ability for the new chargers at the bus depot to run on a backup power supply, if the power grid fails. Knotts says the City can also buy back the electric bus batteries it leases from the manufacturer once the lease ends.
“Once those batteries are taken out of the bus and we do replace them, we can retain those or buy those, and those can be charged and held as back up,” Knotts said.
Additionally, Knotts says the seven new electric buses replaced old diesel ones. Now that those diesels are past their useful life, they belong to the City, so they can be kept on hand in case of emergency.
“When we do have issues with chargers, and we have issues with diesel buses too, we can put those back into the system, and the customer doesn't feel that reduction in service,” Knotts said.
Park City Transit currently has 13 electric buses in rotation, with more on the way. The full fleet is 43 vehicles, but that includes some that don’t yet have electric technology available to them, like shuttle services for people with disabilities and the Main Street trolley. The City also acquired diesel buses in 2016, and as part of an agreement with the Federal Transit Administration, the City has to hold onto them for the span of their useful lives—12 years or 500,000 miles—or pay interest back to the federal government. Knotts says those buses could be replaced in 2028.