This morning, the DesignLine EcoSaver IV hybrid electric bus made its passenger-carrying debut for New York City Transit.
DesignLine EcoSaver IV hybrid electric bus makes NYC debut early this morning on the M42 route (42nd Street Crosstown)
The DesignLine EcoSaver IV bus is different from other hybrid buses already in the NYCT fleet because it is a series hybrid. That means that the engine, in this case a turbine, is only used to charge the batteries, and not to directly power the vehicle.
The turbine fills the role of “Auxiliary Power Unit” (APU). The batteries in turn power the electric motor, which makes the bus go. There are many advantages to a series hybrid, and for this bus overall, one of which is the fact that the bus can operate in pure electric mode, with the turbine off (producing no emissions), in some situations. In all other situations, the turbine is running at the most efficient speeds to keep the batteries at an optimal charge, totally independent of the bus’s immediate acceleration needs.
The story of how this bus design, which originated in New Zealand, came to be for sale to bus authorities in the US, is interesting, and worth the short read.
I came away from my ride on the bus’s maiden voyage pretty impressed with its quietness and performance. I have no doubt that the fancy hybrid driveline is well engineered and quite capable. My only reservations are over how well the not-so-glamorous parts of the bus will hold up in the severe service conditions experienced here in New York City. How will the plastic straphangers and the full length glass doors and the flooring, etc., hold up? Until now, NYCT has generally only purchased proven, “heavy-duty” buses. I don’t know if the DesignLine EcoSaver IV hybrid electric bus can be considered “heavy-duty” in and of itself, but if it survives NYC’s streets and residents, leading to an expansion of the initial eight bus fleet to up to 80 with options, then it will certainly have proven itself worthy.
Here is a gallery of photos I took today of the bus’s grand debut: PHOTOS
Edit: As pointed out by Joe in his comment, the other hybrid buses in the NYCT fleet (Orion VII) are also series hybrids. So the DesignLine EcoSaver IV is not different in that regard.