When it comes to deploying plug-in electric cars in municipal fleets, Indianapolis appears to be leading the way.

The city announced last week that it will replace 425 non-police-pursuit vehicles with electric cars and plug-in hybrids by early 2016, as it works toward a goal of converting the entire fleet to "post-oil technology" by 2025.

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The influx of plug-in cars will give Indianapolis the largest fleet of its kind in the U.S., the city says.

And the transition is made possible in large part by a new financing model developed by Vision Fleet, which is partnering with Indianapolis on the green-fleet effort.

Known as the "Clean Mile Solution," this financing model combines all of the costs of ownership--including purchase prices, fuel or electricity costs, and maintenance--into one set fee.

It's a method that resembles a popular model used to finance clean-energy projects, GreenTech Media notes--one that has dramatically increased the adoption of those types of projects.

Under this setup, Indianapolis will pay for the use of cars over time, without owning them outright.

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This eliminates the typically higher upfront purchase costs of electric cars compared to internal-combustion models.

City officials say it will actually make the plug-ins--collectively dubbed the "Freedom Fleet"--less expensive to operate than the gasoline sedans they'll replace.

They claim each gasoline-powered sedan would have cost taxpayers roughly $9,000 per year over the next decade, while the new electrified vehicles will only cost around $7,400, saving $1,600 per year.

That includes savings of 2.2 million gallons of gasoline over the next decade, at a projected cost of $8.7 million, for the fleet of Nissan Leaf, Chevrolet Volt, and Ford Fusion Energi plug-ins.

2014 Chevrolet Volt

2014 Chevrolet Volt

As part of its $32 million, seven-year contract with the city, Vision Fleet will also provide usage data to improve fleet efficiency.

Prior to finalizing its contract, the company used onboard telematics equipment to monitor vehicle use, leading to a reduction in fleet size by 100 cars.

Vision Fleet will install similar equipment in its electric cars. Data collected can be used to improve efficiency by suggesting changes to driving styles, routes, and charging times, or even facilitating reimbursement for at-home charging.

Maximizing electric miles for the Volt and Fusion Energi cars in the fleet will be important, as many of their environmental and economic benefits are lost if drivers treat them like ordinary gasoline cars and don't plug them in.

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