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Cummins Unveils SmartEfficiency Initiative Improvements for Transit Buses


Cummins has unveiled the SmartEfficiency initiative for transit buses. As part of the SmartEfficiency initiative, Cummins revealed a number of improvements, including the the ISL G Near Zero (NZ) NOx natural gas engine, the isolated engine coolant loop system, and a new SmartSupport service program.

The isolated coolant loop for transit buses using the ISL G natural gas powertrain improves reliability and reduces downtime. A water-to-water heat exchanger will be mounted on the ISL G, and will provide heat to the passenger compartments, as needed, while providing a self-contained coolant flow to the engine compartment area. This new approach reduces potential coolant leakage or air infiltration for better Exhaust Gas Recirculation (EGR) cooler reliability and durability. Installation of the isolated coolant loop becomes standard in transit buses beginning January 2017.

The Cummins Westport ISL G Near Zero (NZ) offers transit authorities an alternative product that is certified to optional near-zero emissions standards. The ISL G NZ is built off the current ISL G platform, but requires Closed Crankcase Ventilation (CCV) that prevents crankcase emissions, a larger maintenance-free Three-Way Catalyst (TWC), and a unique engine calibration. Together, these improvements will allow the ISL G NZ to certify to 0.02g/bhp-hr, or 90 percent below the current U.S. Environmental Protection Agency (EPA) NOx standards, and provide up to a 15 percent reduction in CO2 emissions. The ISL G NZ can power transit and shuttle buses weighing up to 66,000 lbs. gross vehicle weight.

In order to provide greater service and support for transit authorities, Cummins is currently piloting a new service program, called SmartSupport, where Cummins will proactively replace critical engine components to reduce unscheduled downtime.

“The proactive replacement schedule is based on the predicted life of the component,” said Kartik Ramanan, Cummins General Manager of Global Bus. “With the future integration of Connected Diagnostics, Cummins will be further equipped to keep the transit authority fleets operating, and replace critical components when needed.”