"In the end we wanted to design a bus around the system and not a system around a particular bus," said DTA General Manager Dennis Jensen, who explained that original plans to bring a quick-charge bus to Duluth have been scrubbed in favor of another variety of electric bus: an extended-range model.
The DTA was awarded a grant worth $6.3 million from the Federal Transit Administration in February 2015 to receive six buses that would charge in minutes and hold a charge for 25 miles. But regular charges would have brought a reduction in popular cross-city routes and forced passengers to transfer buses more often. Also, the quick-charge buses couldn't be counted on to maintain comfortable cabin heat during cold-weather months without diminishing the operating range of the buses, Jensen said.
The DTA will continue to share roughly $1.1 million in the total cost of nearly $7.5 million for the buses. The new delivery date is expected to be sometime after June of next year.
The DTA and the bus manufacturer, Proterra of Greenville, S.C., are now collaborating on an extended-range bus model that will charge overnight and be used for several hours a day during peak morning and late-afternoon hours.
Under the quick-charge option, the DTA would have had charging stations at its new Duluth Transportation Center downtown on Michigan Street and at the University of Minnesota Duluth, which, along with the hospitals and mall, is among the most popular destinations for DTA passengers. But disturbing the campus became yet another issue with the quick-charge buses, and Jensen said the extended-range buses will be able to charge in the DTA's garage on Michigan Street in Lincoln Park.
Currently, the DTA is working with Proterra on adding supplemental heat to the buses — both for passengers and the driver. Jensen isn't convinced base models would generate enough heat.
"We've done a lot of studies on this," Jensen said. "We don't feel the battery will give you that level of heat required here. We're looking at supplemental heat — a cold-weather package."
Jensen said he's been in contact with the Worcester Regional Transit Authority in Massachusetts, where Proterra electric buses already are in operation. While not as harsh as Duluth's, Worcester's winters have posed a significant testing ground for the electric buses. To hear their top official tell it, Jensen and his staff are right to pursue supplemental heat sources — such as kerosene heaters — that don't draw electricity from the battery.
"We are finding them to be very efficient," said Jonathan Church, chief executive officer and administrator for the WRTA, of the electric buses. "When the cold weather comes, their performance does go down, using more electricity for heat. But overall their performance has been good for us, and we've been pleased."
The original federal grant process, which included applications from 70 cities and awarded buses to 10, was designed to prove how quick-charge buses would work in harsher climates. Rep. Rick Nolan, DFL-Crosby, who serves on the House Transportation Committee, said at the time that Duluth was "probably the best city in the nation to demonstrate fast-charging electric bus technology."
But in eschewing the quick-charge buses even before their arrival, Jensen believes the process to have worked.
"The whole point of the grant was to look at Duluth as a good test market," he said. "It just wasn't working for us."
With its low temperatures averaging single-digit degrees in the winter months and its long, narrow and hilly landscape, the city requires something more than a quick-charge battery could provide. It requires durability, and the FTA, Jensen said, is continuing to comply with the city's needs.
"When a bus is operating on a flat, dry street, it takes less current than going up hills in 3-4 inches of ice and slush and so forth," Jensen said.
The DTA already uses supplemental heating systems on its diesel and hybrid diesel buses in an attempt to keep the temperature at about 50 degrees. The driver compartments are also designed with added heating to stay warm despite the frequent opening and closing of doors.
"The last thing you want," Jensen said, "is a driver with cold feet."
The notion of forcing riders to transfer downtown as buses charged also played a role in the DTA reconsidering quick-charge buses. Earlier this year, the DTA faced some rider backlash when it opened the Duluth Transportation Center and included fewer of the popular "through routes" that take riders from all over the city to the hospitals, mall and colleges and universities without transferring.
The DTA listened to the criticism and quickly restored the through-routes. Jensen said he and his staff were loath to test riders' patience again by reintroducing more transfers.
"We looked at a 10-minute charge as meaning (riders) would have to get off the bus and wait for another bus," he said. "We felt it would be too much of an impact on our operations."
©2016 the Duluth News Tribune (Duluth, Minn.) Distributed by Tribune Content Agency, LLC.
