Regional Transportation District officials are casting a wary eye on the prospect of a 100% electric bus fleet in its systemwide electrification planning to meet Gov. Jared Polis’ greenhouse gas reduction mandates.

Problems with electric vehicles’ range, winter performance and reliability have RTD assessing the balance between emissions reductions and its mandate to provide affordable, reliable service to the public.

In 2021 Denver said it was going to replace 1,000 diesel buses with electric versions, but in the spring of 2022 RTD cancelled an $18 million plan to buy 17 buses, saying they didn’t have enough space or charging infrastructure to support them.

“That’s the thing that everyone wants to go buy — some battery buses,” Stuart Summers, spokesperson for RTD told The Denver Gazette. “The part that people don’t realize is where are you going to store them? How are you going to charge them? Also, they’re not like a diesel bus (in) that you won’t get maybe the same mileage out of them. So, then you have to rethink of all your routes. We have some very long routes that go clear across the district.”

Currently RTD has 36 operating electric buses on the 16th Street Mall route, Summers said.

“If we get a battery electric bus, it may not work on that specific route because you may go one or two runs and then you have to go back to get it recharged,” Summers said.

Electric busses don’t work as well during cold because heating the passenger compartment depletes the battery much faster, he said. Internal combustion buses use waste heat from the engine to keep passengers warm.

“We’re doing a big assessment right now to say, in order for us to transition correctly and successfully, how do we do it in the right approach,” said Summers. “What facilities would be needed or equipment or training? And then how could we start to phase in route modeling and thinking about it in the holistic approach.”

“Battery electric buses are a quickly developing technology and are being added to fleets in Colorado by school districts and transit agencies,” Matt Inzeo, spokesperson for the Colorado Department of Transportation, said in a statement.

“As manufacturers improve electric bus technology to address current limitations, transit agencies can use a mix of operational strategies to ensure reliability year-round, including pre-conditioned batteries, indoor vehicle storage, data-driven route modeling, and driver training,” Inzeo said.