After over a year of testing, Chicago is ready to commit to all-electric buses.

The Chicago Transit Authority (CTA) took delivery of two electric buses in 2014, and found them satisfactory.

So the city now plans to purchase 20 to 30 all-electric buses over the next few years, as part of an overall modernization of its fleet.

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The CTA claims to be the first major transit agency to put all-electric buses into daily revenue service. Its pair of buses have operated continuously since October 2014.

Both are 40-foot models made by New Flyer Industries.

Each is equipped with a 300-kilowatt-hour lithium-ion battery pack, which the CTA says provides a range of 80 miles.

Chicago Transit Authority electric buses

Chicago Transit Authority electric buses

Charging takes three to five hours, and is done overnight while the buses are idle.

The pair have already carried around 100,000 passengers on 13 routes--racking up 25,000 in-service miles.

No significant mechanical issues cropped up during testing, according to the CTA. The buses' battery packs are intended to last their entire service lives--meaning about 12 years.

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Officials claim the emissions reductions from operating the two buses is the equivalent of removing 14 internal-combustion cars from the road, and adds up to $39,000 in health-benefit savings.

In an "average year of use," the CTA expects each bus to save $25,000 in fuel, and $55,000 in public-health costs.

The agency will issue a request for proposals later this year, for both additional 40-foot electric buses and charging stations that will be placed along their routes.

Chicago, by Flickr user Mr Hicks46 (Used under CC License)

Chicago, by Flickr user Mr Hicks46 (Used under CC License)

The entire project will cost an estimated $30 to $40 million, which will come from a yet-to-be-finalized group of Federal funding sources, the CTA said.

In addition to all-electric buses, the CTA will continue to operate diesel-electric hybrids, which currently make up about 15 percent of its fleet.

MORE: Proterra Electric Bus Travels 700 Miles In 24 Hours With Regular Recharging (May 2014)

As part of a fleet modernization effort first announced by Mayor Rahm Emanuel in 2012, the CTA is also recently retired older vehicles that date back to 2000-2002, and performed overhauls on newer vehicles.

That includes adding particulate filters to some diesel buses, in order to reduce harmful particulate-matter emissions.

[hat tip: Brian Henderson]


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