CSR is pursuing the longer term goal of the design and manufacture of a new passenger steam locomotive targeted at higher speed, passenger and commuter operations.  There have been roughly 60 years since the last major steam locomotive developments, a time in which materials sciences, combustion engineering, boiler engineering and biofuels research has progressed significantly, aided by modern computer modeling. 

We would like to make clear, though, that a modern steam locomotive will not resemble locomotive 3463; rather that locomotive would be a modern, computerized, streamlined prime mover designed to meet the needs of the passenger railroad industry at least with respect to:

  • Meeting all Government Safety and Emissions Regulations (FRA & EPA)
  • Following All Relevant AAR & APTA Standards
  • Single Person Operation of 1 or More Locomotives, Including in Mixed Consists with Diesels
  • Fully Automated Boiler Control
  • Capable of Push-Pull and Multiple Unit (MU) Operation
  • Bi-directional Operation at Full Service Speed
  • Dynamic Brake Capability (Counter Pressure Braking)
  • Axle Loadings
  • Clearances
  • Horsepower Rating
  • Increased Range to Passenger Diesels
  • Reduced Maintenance Costs Compared to Passenger Diesels
  • Climate Controlled End-cab Including Railroad Industry Standard Cab Amenities
  • Streamlined Carbody
  • Modular Design / Construction to Ease Maintenance
  • Advanced Adhesion System / Traction Control
  • Wide Range of Speed and Load Capability
  • Service Speed Limit

The newly-designed passenger steam locomotive would need to fulfill the needs of the passenger railroad industry, exceeding the expectations of the industry on issues including performance, emissions and maintenance costs, all the while having lower life-cycle costs than diesel-electric passenger locomotives. 


The modern steam locomotive, by virtue of its external combustion boiler system, can easily and efficiently burn solid, liquid and gaseous fuels, providing flexibility in the combustion of advanced and developmental biofuels not afforded through internal combustion prime mover engines of diesel-electric locomotives.  Working in collaboration with the University of Minnesota's Natural Resources Research Institute, a  leader in the development of torrefied biomass technologies, CSR will refine a sustainable biofuel that can be burned in the mechanically-simple, yet thermally-efficient gas producer combustion system of a modern steam locomotive. 


The majority of  intercity passenger rail in the U.S. operate over tracks with the capacity for "higher speeds" of 110-125 mph. However, in the absence of modern steam engines capable of reaching those speeds quickly, passenger rail providers are forced to rely on diesel-electric passenger locomotives, which develop maximum horsepower at low speed. Combined with inefficiencies of traction motors encountered at high revolution, these trains exhibit sluggish acceleration above 40 miles per hour, hampering their ability to reach full potential at 110 or 125 mph.  By comparison, the modern steam locomotive develops and maintains maximum horsepower above 40 mph, enabling higher speed acceleration than alternatives available today. Initial computer simulations suggest that the CSR's modern steam engine will significantly out-accelerate a modern diesel-electric locomotive to 110 mph, meaning that passenger operators would be able to realize electric-like acceleration at or below the cost of the diesel-electrics they currently use.

As a point-in-case, Amtak's new Chicago-St.Louis higher-speed rail corridor relies upon two diesel-electric locomotives to haul five-or-more cars to 110 mph in order to maintain the acceleration needed to make the schedule.  This results in twice the capital, maintenance expenses and increased fuel cost.  The graph below is representative of the drawbar horsepower of diesel-electric locomotives and the testbed locomotive 3463 relative to speed.

Note that it takes two diesels to match the drawbar horsepower of the rebuilt ATSF 3463, with the latter producing in excess of 5,000 horsepower between 55 and 125 miles per hour, the "sweet spot" in higher-speed rail operation.


In addition to being carbon-neutral and accelerating quickly, modern steam locomotives could be cheaper to operate and maintain than existing passenger rail trains. Electric railroads require the construction and additional maintenance of an overhead wire power system (known as catenary), a system that costs up to $2-3 million per mile to construct and upwards of $12,000 per mile to maintain each year.

Due to innovations in boiler maintenance, which traditionally accounted for up to 90% of all maintenance expenses, modern steam trains are expected to be cheaper to maintain and simpler to fix than current locomotives, while eliminating the need for catenary and its related expenses. CSR's Director of Engineering, Shaun McMahon, is a world-leader in modern steam locomotive boiler maintenance. Currently running modern steam in Ushuaia, Argentina, his utilization of Porta Treatment in his boiler water allows him to run his locomotives 300+ days per year with only one washout every 12 months (as compared to the 30 day washout cycle in the U.S.). In addition, he has run his locomotives with zero boiler maintenance time or expense under those harsh conditions for more than a decade.

What used to account for 91 cents of every maintenance dollar has been reduced to less than 8 cents, a savings resultant from 75 years of advanced research on modern locomotive boiler systems.

Burning torrefied biomass in a modern steam locomotive is also notably less-expensive than burning diesel in a diesel-electric locomotive, attributable to the low cost per million BTUs.  Combined with the previously-described technologies, CSR will reduce cost at every stage, from infrastructure construction and maintenance, to train maintenance and fuel cost.