LOUISVILLE, Ky. (WDRB) - Ride the bus for free and help the environment.

That's the idea behind ZeroBus.

The new fleet of zero-emission TARC buses run on electricity, and will replace the diesel-powered trolleys.

Free rides are available to passengers along Main, Market and 4th Streets.

The fleet includes 10 buses and two charging stations.

They cost a total of $11 million, the majority of which is covered by federal and state grants.

Louisville Metro contributed $500,000 to the project.

Officials say the new buses will save TARC about $10,000 a year.

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