The Altoona Works BP4 is a B-B battery-electric locomotive rebuilt by the Altoona Works of the Norfolk Southern Railway. It was created in 2007 by replacing the diesel

prime mover Prime mover may refer to: Philosophy *Unmoved mover, a concept in Aristotle's writings Engineering * Prime mover (engine), motor, a machine that converts various other forms of energy (chemical, electrical, fluid pressure/flow, etc) into energy ...

of an

EMD GP38 The EMD GP38 is a four-axle diesel-electric locomotive built by General Motors Electro-Motive Division between January 1966 and December 1971. The locomotive's prime mover was an EMD 645 16-cylinder engine that generated . The company built 70 ...

(Norfolk Southern #2911, formerly Conrail #7732) with 1,080 12-volt lead-acid batteries and associated control equipment. The converted locomotive was redesignated Norfolk Southern #999.

Design

Despite appearing somewhat similar to a conventional

diesel electric locomotive A diesel locomotive is a type of railway locomotive in which the prime mover is a diesel engine. Several types of diesel locomotives have been developed, differing mainly in the means by which mechanical power is conveyed to the driving wheels ...

, the BP4 has no diesel engine; battery charging is provided by plugging in an external power source. Battery life is extended by the use of

regenerative braking Regenerative braking is an energy recovery mechanism that slows down a moving vehicle or object by converting its kinetic energy into a form that can be either used immediately or stored until needed. In this mechanism, the electric traction mo ...

, which returns about 35% of braking power to the batteries. The BP4 is designed to operate 3 shifts on a single battery charge. This conversion significantly alters the external appearance of the locomotive, with the cab (which is actually brand new) being moved forward on the frame to make room for a large louvered battery box, which takes the place of the locomotive's

long hood The long hood of a hood unit-style diesel locomotive is, as the name implies, the longer of the two hoods (narrower sections of the locomotive body in front and behind of the cab) on a locomotive, particularly American-type freight locomotives. ...

. The fuel tank is similarly replaced with another battery box. BP4 development was undertaken by Norfolk Southern, along with Brookville Equipment, Penn State University, the

United States Department of Energy The United States Department of Energy (DOE) is an executive department of the U.S. federal government that oversees U.S. national energy policy and manages the research and development of nuclear power and nuclear weapons in the United Stat ...

, and the

Federal Railroad Administration The Federal Railroad Administration (FRA) is an agency in the United States Department of Transportation (DOT). The agency was created by the Department of Transportation Act of 1966. The purpose of the FRA is to promulgate and enforce rail saf ...

. $1.3 million in federal funding subsidized the program. The locomotive was initially converted in 2007; after initial battery issues, a better battery management system was installed in 2009. A further rebuild was undertaken in 2014, changing the batteries from lead-acid to lead-carbon. Despite the continued tweaking, NS 999 was unable to fulfill the railroad's requirements and the project was dropped. Norfolk Southern put the 999 up for auction, along with several other locomotives, in November 2019. 999 was purchased by Rail Propulsions Systems, where it was upgraded for eventual use in the Los Angeles Basin region.

References

B-B locomotives Electric locomotives of the United States Battery electric vehicles EPA Tier 2-compliant locomotives of the United States Norfolk Southern Railway locomotives Rebuilt locomotives Standard gauge locomotives of the United States Unique locomotives Shunting locomotives {{US-train-stub