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New York City Transit unveils greener buses

Paul Fleuranges: I'm Paul Fleuranges with a with a "Going Your Way Greener" podcast on TransitTrax, New York City Transit's podcast service. Listen closely.

(SOUND: White noise)

If you don't hear anything, that's a good thing. Because New York City Transit's new turbine-powered hybrid-electric bus is as quiet as it is green. It's a new breed of bus, running in service as part of an eight-bus, 90-day evaluation. Yet another example of the agency’s ongoing effort to examine new technology that will help us reduce emissions and provide more economical and environmentally friendly service. Joe Smith is Senior Vice President for New York City Transit's Department of Buses.

Joe Smith, Department of Buses: It's a ground breaker. There's no other turbine engines around, so it's a turbine engine in our duty cycle, and we want to see if it can survive. If it can survive and it operates as efficient and as reliable as a jet plane does, then it’s going to really, really improve our overall operations.

Paul Fleuranges: The bus also has a new sleeker shape, curved mirrors and large front window that give the impression the bus is smiling. But the key feature is that diesel turbine engine.

(SOUND: Engine running softly, quietly)

The first of its kind to operate in New York. The majority of Transit's 46-hundred bus fleet runs on a diesel piston engine. The buses are manufactured by DesignLine International USA in Charlotte, North Carolina. Tim Duncan is Electric Vehicle Production Manager.

Tim Duncan, Electric Vehicle Production Manager, Design Line International:
The whole bus is designed so that the batteries run the electric motors and its two electric motors that drive the propulsion system to move the bus along the ground and then, as the batteries get flat, the turbine generator starts up and will charge the batteries. And when the batteries get fully charged it will shut down and the vehicle will run on zero emissions; it’ll run for up to two hours without any emissions, and then when the batteries get low again, then the turbine kicks in.

Paul Fleuranges: This turbine is slightly different than the turbines used for jet engines. Instead of forcing out hot air to propel itself, this turbine spins at 96-thousand RPM's and runs a generator.

Tim Duncan: Well what it allows us to do is to drive the vehicle, and it ramps up and ramps down as we're propelling the vehicle across the road, but the turbine is running at one fixed speed, and it’s running at its most efficient point. So the turbine is running efficiently but it’s allowing the bus to operate the most efficient way possible as well. All the particulates are all burned off. When a conventional diesel bus runs down to an idle, there are some particulates that come out when you accelerate. We're just running at one fixed speed, a very fast speed, and constant temperature so there's no particulates at all.

Paul Fleuranges: Like the rest of the hybrid fleet, the new bus has regenerative braking, which recharges the batteries each time the bus operator applies the brakes.

(SOUND: Bus braking, beeping)

This energy-saving system is similar to braking systems on our New Technology subway trains. Smith adds this is the only bus in New York City Transit’s fleet that meets the EPA’s 2010 emissions standards without the need for treating the exhaust. And that's not all:

Joe Smith: How it differs from a regular bus is it doesn't have a water pump, radiator, starter, injectors it doesn't have all these items and it doesn't require the maintenance that these items bring with them, so it’s going to revolutionize our maintenance on the vehicle. It's like a bridge; every technology brings you a little bit closer to where you want to be, but what's great about this technology is that it’s reduced maintenance costs and maintenance costs are a brig driver in our budget, and without having oil and without having all these other issues to deal with it absolutely is the way to go.

Paul Fleuranges
: Other features include an efficient and long-lasting interior LED lighting system, a contact-less sensor system for air assist rear exit doors, a flip-out ramp for wheelchairs by the front entrance, and disc brakes on all wheels.


A 35 foot long version of the bus operated in Manhattan and Queens over a 30-day period back in the fall of 2007. This pilot is the second-phase test of a greater number of buses, built to New York City Transit specifications. Structural testing is currently underway as part of the New Bus Qualification program in addition to this in-service testing. The buses can seat either 35 or 37 depending on the configuration, with 30 standees. They will operate on some cross-town routes in Manhattan, especially the M42, during the evaluation period.

(SOUND: Bus driver announcing next stop.)

So the next time you see a bus heading across midtown, take a listen. You might not hear anything, which is good news for the environment. With a "Going your Way Greener" podcast, I'm Paul Fleuranges.
Thanks for listening and thanks for riding with New York City Transit.