NRE 3GS21B

NRE 3GS21B
A new NRE 3GS21B locomotive in the Union Pacific scheme.
Type and origin Power type Diesel-electric Builder National Railway Equipment (NRE) Model 3GS21B Build date December 2006 (2006-12) – Present Total produced 182
Specifications Gauge 4 ft 8+1⁄2 in (1,435 mm) Prime mover Cummins QSK19C (×3) Engine type Diesel engine (×3) Aspiration Turbocharger (×3) Cylinders 6 (×3)
Performance figures Power output 2,100 hp (1,570 kW)
Career Operators See list

The NRE 3GS21B is a low-emissions diesel genset locomotive built by National Railway Equipment (NRE). Instead of a single prime mover, the NRE genset locomotive is powered by three separate 700 horsepower (522 kW) Cummins QSK19C engines providing a total power output of 2,100 horsepower (1,570 kW). Each engine could be individually started or shut off depending on load reducing overall diesel emissions and improving fuel efficiency.^[1] More than 150 of the 3GS21B genset locomotives have been produced to date, with the majority of these units being manufactured at NRE's Mount Vernon shops in Southern Illinois.^[2] In addition, three road slug models have also been produced.