MPE-X Low Emissions Locomotives

MotivePower is committed to assisting railroads in their ongoing efforts to reduce locomotive emissions and improve operating efficiencies. We designed and manufactured the only four liquefied natural gas locomotives operating in North America and were the first to provide Tier 2 low horsepower locomotives and Tier 2 commuter locomotives.

Ultra Low Emissions Multi-Engine Switchers:

Replacing the single conventional engine on switchers with two or more smaller, more technically-advanced engines offers significant operational savings and environmental benefits. MotivePower's first three-engine locomotive is available for field demonstrations. A two-engine model will also be available.

  • 2 or 3 engine design
  • Tier 3 nonroad emissions levels
  • Integrated automatic engine start/stop
  • High visibility operator's cab
  • QES-III microprocessor control system
  • Pressurized engine carbody
  • Built-in system redundancy
  • 35% or more fuel savings depending on duty cycle
  • 80-90% reduction in NOx
  • 70-80% reduction in PM
  • Simpler and reduced maintenance requirements (modular/mobile maintenance)
  • High tractive effort
  • Improved reliability


MP21B Multi-Engine MP20B Single Engine MP20C Single Engine
Horsepower 2,100 (700 bhp x 3) 2,000 thp 2,000 thp
Engine Cummins QSK-19 (Tier 3 nonroad) MTU-Detroit Diesel 12V4000 (or equivalent) MTU-Detroit Diesel 12V4000 (or equivalent)
Traction motors D77 / D78 D77 / D78 D77 / D78
Maximum speed (nominal) 50 mph 70 mph 70 mph
Continuous tractive effort 55,000 lbs 55,000 lbs 82,000 lbs
Starting tractive effort 85,000 lbs 85,000 lbs 128,000 lbs
Weight (nominal) 275,000 lbs 277,000 lbs 390,000 lbs
Length 59' 2" 59' 2" 68' 2"
Height Plate C / Plate L Plate C / Plate L Plate C / Plate L
Fuel capacity 2,500 gal 2,500 gal 3,900 gal
Alternators 1800 rpm constant speed Kato 350 KVA variable speed Kato 350 KVA variable speed
Air compressor Electric driven rotary screw WLN WLN
Dynamic brake Optional Optional Optional
Locomotive control Q-Tron QES-III microprocessor Q-Tron QES-III microprocessor Q-Tron QES-III microprocessor
*1,400 bhp model (MP14B) coming soon *Tier 2 MPXpress commuter locomotive also available

Download a printable version of the MPEX Low Emissions Locomotives brochure.