Columbia is at a renewable energy crossroads.
With three out of 14 diesel buses currently beyond their useful life, the city is getting ready to replace them.
The days of buying new diesel buses for Columbia are over as the city attempts to make more sustainable energy choices.
Compressed natural gas and electric both present themselves as preferable alternatives to diesel. But deciding between natural gas and electric means weighing both financial and environmental costs.
On paper, electric buses look promising. They cost more upfront — each new electric bus could cost the city up to $800,000, compared to about $500,000 for one using compressed natural gas. However, they generally cost less in fuel and maintenance, making them potentially cheaper in the long-term. They’re also decisively less harmful to the environment.
The city has had unfortunate experiences with electric buses. In 2016, several new electric models were added to the city’s fleet through a leasing arrangement. Problems began to crop up quickly, with one catching fire, according to Columbia City Manager John Glascock. The faulty buses were returned.
“They just were not very well made,” said Michael Sokoff, transit and parking manager for the city. “We just would have problem after problem after problem.”
Still, Columbia gave electric a second chance. The city’s fleet now has four electric buses that have been in service for about a year.
As of August, those four buses had traveled 49,789 miles, saving 10,621 gallons of diesel fuel and reducing greenhouse gas emissions by 136 short tons, according to Sydney Olsen, spokesperson for the city, but they’re still under warranty.
“You know how this goes,” Sokoff said. “Once the warranty’s out, things start to happen.”
As such, Sokoff explained that he wants to run the four battery-powered buses through another winter and another summer, collecting data throughout the year to see how they hold up. Once they’ve proved their dependability, he said he will feel more comfortable going all-in.
“We want to make sure that before we commit to completely transitioning,” Sokoff said, “that we have a reliable fleet to transition to.”
Glascock echoed that sentiment during the Columbia City Council’s Oct. 18 meeting.
“We would like to really try them out first before we start investing heavily in them,” he said. “We’d love to invest in electric.”
Buses that run on natural gas are an environmental improvement over diesel and have proved reliable, which is why they caught the eye of city officials amid electric hesitancy. But they still use an internal combustion engine and contribute to emissions, and the city’s interest has drawn the concern of local environmentalists.
At the Oct. 18 meeting, Carolyn Amparan of the Sierra Club’s Osage Group stepped up to the lectern to emphasize the city’s effort to reduce emissions as a 2035 deadline, set by the city’s Climate Action and Adaptation Plan, creeps ever closer.
“Every single one of these decisions begins to be important,” she said.
Amparan asked that future cost analyses include social costs, noting that compared to electric, buses that run on natural gas contribute more not only to greenhouse gases but also to air pollution, which can affect pedestrians.
Despite the improvement over diesel emissions, emissions of carbon monoxide, methane and nitrogen oxides are still prevalent in CNG bus exhaust at a concerning rate, according to a study published last year by the National Institutes of Health.
The Sierra Club representative also urged the city to look to other transit systems that have adopted electric buses for guidance about ways to implement such a program at home — without fear of another bus bursting into flames.
Sokoff said that while the city does keep an eye on the latest data, Columbia’s specific geography and climate make it difficult to compare to other cities with a longer history of electric transit.
By watching how the current fleet performs on the city’s exact routes with hills, freezing winters and scorching summers, officials hope to better understand the potential of electricity as the sole fuel for the city’s bus fleet.
“They will be electric down the line,” Sokoff said. “We’re just asking for … a stopgap with CNG buses until we’re comfortable going full electric.”
Mark Haim spoke at the recent council meeting on behalf of Mid-Missouri Peaceworks. He agreed with Amparan, adding that choosing buses that use natural gas, even in the interim, represents a problematic investment in fossil fuels.
“Whenever you invest in fossil fuel infrastructure, you intend to use it for an extended period of time,” Haim said.
He also pointed to the effects of fugitive methane emissions, referring to the methane that makes its way into the atmosphere during the natural gas production and distribution process.
Fugitive methane emissions, though a smaller contributor to overall greenhouse gas emissions, are “a significant driver of short-term warming,” according to the World Resource Institute.
“We should be phasing out our compressed natural gas facility rather than buying new equipment that’s going to need to use that facility,” Haim said. “If we’re serious about meeting the goals of the Climate Action and Adaptation Plan, we’ve gotta take action now.”
Nevertheless, officials are anxious to replace three diesel buses. If the city can’t wait another year until the electric buses have been thoroughly vetted to buy replacements, compressed natural gas models could be the fill-in.
If new units are purchased soon and the city takes the advice of Public Works to pump the brakes on electric, natural gas will be the answer.
“We still need buses,” Glascock said. “The diesel ones are down quite often.”
The questions that remain are when the city will buy the new buses, and whether the council will agree with Public Works to not commit to electric until transit officials are comfortable doing so.
Columbia Public Works Department is aiming to have a report prepared for next Monday’s council meeting to further explain replacement options per the council’s request for additional context.