The car then runs off of electric power when idling.

That factors out to about 60 miles per gallon for city driving, while a traditional Ford Crown Victoria only gets about 18 miles per gallon.

The result of increased fuel efficiency, Riney says, is a huge economic incentive for taxi companies to operate hybrid cabs.

On Tuesday Riney will take his argument before the Cambridge License Board in a public hearing. He will also present a petition signed on PlanetTran’s website by various supporters and members of the community.

Riney hopes the hearing will be the last major hurdle in making PlanetTran fully operational.

“I wouldn’t describe the process with the license board as troubling—just rigorous,” Riney said. “the more people that sign the petition, the easier the process will be.”

If PlanetTran is successful in Tuesday’s hearing, Riney is optimistic for the future.

“I hope to have a fleet of taxis to serve the Harvard community in the fall,” Riney said.

—Staff writer Adam C. Estes can be reached at estes@fas.harvard.edu.