Greater Portland Metro and ShuttleBus-Zoom may come together to bring the first electric-powered buses to Maine.

The two bus systems are considering whether to jointly apply for state and federal grants to replace up to a half-dozen aging diesel buses in their fleets with electric ones. Electric buses are more expensive to buy than diesel but run cheaper, cleaner and more quietly, according to Metro manager Greg Jordan and Al Schutz, the director of ShuttleBus-Zoom (also called SH-Zoom), the regional transit service that serves Biddeford, Saco and Old Orchard Beach.

“The future of public transit is electric, not diesel,” said Schutz, who also serves as the head of the Maine Transit Association. “We need to be smarter with our resources, stop polluting the planet. Battery technology has advanced so far and so fast that what would have been impractical and much too expensive just a few years ago is not only possible, but it’s becoming quite practical. With the grants available to us, the time to do this is now.”

An electric bus manufacturer that wants to partner with Metro and SH-Zoom will be in Portland on Tuesday showing off one of its vehicles and giving free rides around the Old Port, the Arts District and other locations at noon, beginning at the Metro office at 114 Valley St.

Passengers who try it out will notice the bus is 5 feet longer, holds twice as many people as Metro’s biggest in-service vehicles and runs much quieter, Jordan said.

That manufacturer, Proterra, is one of several that Metro and SH-Zoom are considering. The California company has sold electric buses that are in operation now in Massachusetts, Connecticut and New York City. But New Flyer, a Winnipeg-based bus manufacturer, is entering into the Northeast electric bus market, too, leasing five vehicles to the Metropolitan Transit Authority for a three-year review in its busy Manhattan corridor.

The two local bus services must decide if they want to join with a particular manufacturer to apply for a Federal Transit Administration (FTA) grant to fund no-emissions vehicles, and seek a share of Maine’s $21 million piece of the federal legal settlement with Volkswagen, the carmaker that cheated in its emissions testing.

The FTA allows bus services and manufacturers to pair up to seek the grants, a way to streamline the procurement process. The bus systems and the host communities that fund them will have to make up their minds soon. The application for the federal program, which handed out $55 million in grants in 2017, is due in June.

The managers say going electric would have no impact on rider fees, but might allow the services to expand, and eventually lead to on-demand bus stops.

A 2016 Columbia University study of New York City’s public bus fleet, which includes a mix of vehicles powered by diesel, hybrid and compressed natural gas, found that switching its fleet over to electric buses would save the city nearly 500,000 metric tons of carbon dioxide emissions a year.

Unexpectedly, that same study showed buses powered by natural gas, like Greater Portland Metro’s, produced more emissions than regular diesel buses because they were 25 percent less fuel-efficient.

That study also looked at the financial impact of converting to electric. It found that electric buses costs about $300,000 more per bus to buy than diesel buses, which in New York City run about $450,000 to $750,000.

Jordan said gas-powered buses like the ones that Metro has mixed into its fleet cost slightly more than diesel, but not by much, calling them basically comparable.

The study concluded that, given the favorable difference between electricity and fuel costs, and the lower maintenance costs for electric buses, the overall lifetime cost of an electric bus is about 12 percent less than the cost of a diesel bus.

It concluded, however, that it would take about 7½ years for an investor funding a new electric bus purchase to recover the money, which might make it harder for municipalities to raise capital for them.

The 37-vehicle Metro fleet is now a half-and-half mix of diesel buses and some newer buses that run on compressed natural gas, Jordan said.

The buses that operate on the peninsula are bigger, seating around 35 people, and more likely powered by natural gas, while the buses that serve Freeport are smaller, seating 20 passengers, and are more likely to be diesel.

If Metro goes electric, it would likely replace four diesel buses manufactured in 2004, Jordan said.

At one time, Metro had planned to replace all of its diesel buses with ones powered by compressed natural gas, but Jordan has pulled back from that plan, worried that a problem with the natural gas pipeline capacity could leave the Portland system without a power source and its buses parked.

The buses it has purchased most recently, as part of its regular replacement cycle and a planned expansion to Gorham and Westbrook, have been a mix of diesel and gas buses, he said.

SH-Zoom operates an all-diesel 22-vehicle fleet of buses and trolleys that carry about 400,000 single-trip passengers a year, Schutz said.

The age of his fleet is a critical problem, Schutz said – its oldest bus was put into service in 1999, and its newest is already eight years old.

If SH-Zoom goes electric, he would replace as many of his diesel buses as he could.

Penelope Overton can be contacted at 791-6463 or at:

poverton@pressherald.com

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