3.5 Passenger Motive Power Considerations (New 2017)

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1 Introduction 3.5 Passenger Motive Power Considerations (New 2017) This section of Part 3 primarily contains material pertaining to trains hauled by dieselpowered locomotives with a focus on the characteristics and attributes that affect capital and operating costs. A discussion of Head End Power (HEP) is included as this is an important function to consider in planning and managing locomotives and rolling stock used in passenger service. Through the application of standards and recommended practices, locomotives and rolling stock can be used in many applications and locations across the general railroad system of transportation in North America. This extends to locomotive hauled passenger equipment, which has a high degree of inter-compatibility that is not easily attained in other modes of rail transit. This is due in large part to the efforts of the Association of American Railroads (AAR) and the American Public Transportation Association (APTA) in maintaining specifications, standards, and recommended practices. The use of these materials by operators and manufacturers has allowed for the transfer and use of locomotives and passenger cars between operations from across North America. The application and maintenance of standards also facilitates the movement of passenger rolling stock in freight service, or the use of freight service locomotives on passenger trains for special operations. The American Public Transportation Association s (APTA) Passenger Rail Equipment Safety Standards (PRESS) program has also developed a variety of specifications for vehicles, vehicle subsystems, and appliances used to support passenger service. This section references APTA standards additional information may be found at the APTA PRESS website: Operators, locomotive builders, and rebuilding firms have collaborated to develop locomotive designs capable of supporting intercity and passenger rail services. This collaboration has been affected by section 305 of the US Passenger Rail Investment and Improvement Act of 2008 (PRIIA) that mandated the creation of standard specifications for new locomotives and rolling stock that would receive US federal funding for use in intercity passenger rail service. This mandate has been fulfilled by a committee organized through the American Association of State Highway and Transportation Officials (AAHSTO) as the PRIIA Section 305 Next Generation Equipment Committee (1). The size of this market for locomotives for US intercity passenger rail service has affected locomotive designs being offered for other rail services (such as commuter rail) that are not affected by this mandate. Among the changes to traditional locomotive designs brought about by the adoption of Section 305 specifications is a requirement for energy absorbing couplers (2). It may be challenging to move these locomotives equipped with this appliance in revenue freight

2 2 trains, which has been the standard practice for ferrying locomotives between manufacturers, rebuilders, and service locations. There are many policy and technology developments that are taking place as this section is being written (mid-2017) and practitioners should apply the current state of practice to the issues they face. In particular, AREMA member rail services will want to examine the current regulatory practices on vehicle compatibility and incorporate any required design review or acceptance testing into the scope and timeline of a given project Power for Onboard Systems on Locomotive Hauled Trains While HEP is a significant and visible means of providing power to passenger trains, it is one of many power sources that are used for operating appliances on passenger trains Multiple Unit Trainline Multiple-unit (MU) control and communications functions are commonly configured to use a 74VDC trainline. APTA has published a Recommended Practice document addressing topics relating to trainline configuration: 16. APTA PR-E-RP Recommended Practice for 27-Point Control and Communication Trainlines for Locomotives and Locomotive-Hauled Equipment Abstract: This document defines the Recommended Practices for 27-point MU control and communication trainlines, including functional hardware and interfaces on the vehicles with circuit functions, for use on new/rebuilt locomotives and locomotives-hauled vehicles Main Reservoir Air Many passenger cars are configured to use main reservoir air (commonly maintained at 140 psi.) to operate on-board appliances such as automatic exterior and interior doors, toilets, and to lift potable and non-potable water from storage tanks to the faucets where they are needed. Some appliances will use pressure-reducing valves to supply air at the pressure needed for specific applications (for example water-raising systems typically operate at 40 psi). Servicing and operating needs may require that a locomotive be idled to maintain main reservoir line pressure. Locomotive idling can be avoided by equipping terminals and/or yards with connection to a wayside source of trainline air. AREMA Manual Chapter 6, Part 8, Design Criteria for Passenger Stations contains additional information on design and hardware considerations for providing trainline air from wayside sources.

3 Electrical Hardware on Passenger Cars Passenger cars using HEP will be equipped with transformers and rectifiers that convert HEP to a range of voltages for specific systems (such as HVAC, food service, lighting, communications, and outlets accessible to passengers). Passenger cars will also have a battery backup system for emergency lighting that is commonly operated via batteries carried on the car and charged from the HEP trainline. 32-volts DC is common, however, other voltages may be found on equipment currently in revenue service Special Rolling Stock used with Locomotive Hauled Trains The use of passenger cars with control cabs and depowered locomotives have created opportunities for service providers to extend the functionality of locomotive hauled train sets Cab Cars on Locomotive Hauled Trains The dieselization of passenger rail services in the 1950s was soon followed with the development of cab control cars (commonly referred to as cab cars). Cab cars are coaches that have an engineer s cab, control stand, brake valve, horn, bell, headlight and (on some cars) sand boxes. Today cab cars are widely used, with almost all locomotive hauled commuter rail services (both diesel and electric) in North America using cab cars instead of turning a train. Using cab cars allowed commuter rail operators to avoid turning a consist on a wye or balloon-loop, turning a locomotive on a turntable, or running a locomotive capable of bi-directional road operation around a train. Additionally, using a cab car allows for a quick change of direction of consist (relative to other options) without requiring additional fixed infrastructure in stations or yards. The design convention for cab cars has traditionally included an end-door and diaphragm to facilitate the placement of a cab car within a consist with other cars while not impeding the passage of passengers and train crew. Since 2010, cab car designs have emerged that incorporate crash-energy-management appliances and design techniques. These cars also have a streamline front that does not include an end door. While cab cars offer many advantages, they do have higher initial capital costs relative to a coach. Cab cars are also subject to many of the same regulatory mandates that apply to a locomotive which require scheduled inspections on specified interval. Control and braking equipment, as well as the additional steel that is required to meet enhanced crashworthiness standards, combine to make cab cars weigh more than coaches. Incorporating the characteristics of cab cars into operating simulations and facility design will improve the accuracy of projecting initial capital costs and projection of lifecycle costs.

4 De-powered Locomotives as Cab Cars A number of passenger operators use or have used de-powered locomotives as cab cars. Amtrak uses a number of F-40PH locomotives as cab cars on its state-sponsored corridor service trains, which are referred to as non-powered control units (NPCU). Many NPCUs have doors to accommodate checked baggage or bicycles. All NPCUs have been ballasted to provide a stable ride absent the weight that was provided through the weight of the prime-mover and other appliances that were removed in the conversion. Other railroads have used locomotives as a dedicated source of HEP. In this capacity they have been referred to as auxiliary power units or power cars. Common configurations included using the prime-mover to drive a HEP generator (while removing the traction motors and associated control wiring) or installing a self-contained generator set on a sled. This option allowed commuter operators to use locomotives configured for freight service to overcome equipment shortages and to use locomotives in both freight and passenger services. However this strategy came with the extra weight (and fuel costs) along with the added expense of maintaining locomotive trucks carbody and brake components. Most services that adopted this option have retired their cab/power cars in favor of locomotive provided HEP and cab cars Overview of Motive Power Alternatives for Providing Passenger Service Multiple Unit (MU) vehicles offer an alternative to providing service with a locomotive hauled train. Unlike a locomotive hauled train, a MU vehicle integrates with the passenger carrying vehicle. MU vehicles can operate as single vehicles or can be joined to form multi-car trains. A single MU vehicle may consist of a single car, cars intended to operate jointly in revenue service as a married pair, or as an articulated unit comprised of multiple cars. MU vehicles are principally differentiated by their propulsion source. Electric Multiple Unit (or EMU) vehicles use power from a line-side source, such as an overhead contact system or a third-rail. Diesel Multiple Unit (or DMU) vehicles use power from a diesel engine Electric Multiple Unit (EMU) Vehicles North American light rail and heavy rail rapid transit use EMUs almost exclusively. The exceptions being a small number of services in North America that use DMUs and street cars built without multiple-unit capabilities. Providing services with EMUs requires a significant commitment in electrification infrastructure. Electrification may consist of overhead contact systems using DC or AC power, or 3 rd rail using DC power. The prevailing trend for the past half-century is for electrification to be limited to services that will have a high service frequency and that are expected to carry significant passenger volumes.

5 5 Many older EMUs have been converted to locomotive hauled coaches by removing the electric propulsion equipment and installing couplers and HEP connections that facilitate their use with locomotives and other coaches. This has provided a way to gain additional use from vehicles whose propulsion components may require replacement but whose car bodies remain sound Diesel Multiple Unit (DMU) Vehicles While DMUs (by definition) use diesel engines, they are differentiated by how power from the engine is transferred to the rails. In North America there are DMUs using either diesel hydraulic or diesel electric power. The predominant design for diesel hydraulic driven DMUs uses a horizontally mounted under floor engine connected to a hydraulic torque converter that conveys power to the drive shaft and final drive. Diesel-electric DMUs use a diesel engine connected to a generator that produces power regulated by a power converter that is used to drive electric traction motors. On both types of DMUs, power for auxiliary functions (such as HVAC) may be drawn from the engine providing propulsion or produced by a standalone auxiliary generator depending on the vehicle s configuration Planning Considerations Services Provided with Multiple Unit Vehicles Managers and planners have long looked at multiple unit (MU) vehicles as a way to provide passenger services when demand may vary. MU vehicles can operate more efficiently in terms of energy consumption compared to locomotive hauled trains for short consists. This is largely due to propulsion systems that are sized to propel a single car. Many MU vehicles are equipped with automatic couplers that integrate multiple unit connections and other train line connections. These couplers can facilitate operating plans that require the adjustment in consist sizes to efficiently handle variances between peak and off-peak passenger loads. MU vehicles (operating alone or in a consist) also have a higher ratio of horsepower to trailing tons compared to locomotive hauled consists. This characteristic offers civil engineers an opportunity to design infrastructure with steeper grades with fewer compromises to operating performance (relative to those required for locomotive hauled consists). Some MU vehicles are capable of operating around tight-radius curves, which have allowed some services to develop special infrastructure to reach key destinations via street running. Favorable horsepower per trailing ton ratios also allows for faster acceleration compared to locomotive hauled trainsets, an important consideration for reducing travel times on services scheduled to have multiple stops. While MU vehicles offer a number of potential advantages, careful analysis of lifecycle costs is necessary to securing the potential benefits of using these vehicles. MU vehicles will have a higher initial cost compared to a locomotive hauled coach due to their greater technical complexity. This greater complexity (relative to a locomotive hauled coach)

6 6 requires specialized maintenance throughout vehicle s lifecycle. Service availability may be compromised by regulatory mandates that apply to a locomotive that require scheduled inspections on specified interval. Specific maintenance requirements and vehicle configuration have to be incorporated into service facility design. Many operators of MU vehicles have encountered challenges in ensuring consistent detection using track circuits, with a failure to shunt being the most serious malfunction. This has been especially true for DMUs operating over lines using DC track circuits, the lightweight of DMUs, relative to other passenger cars or freight rolling stock, has been widely cited as the causal factor for their shunting problems. However, shunting problems have persisted with modern DMUs, which have axle loadings approaching that of many locomotives. International research on shunting problems and DMUs have found that shunting problems result from the relatively few wheelsets available to shunt (compared to a locomotive hauled train) which can amplify the effect of any wheel-rail interactions that impede shunting. DMU operators have successfully addressed shunting issues by using a combination of operating rules address sanding, wheel-cleaning blocks mounted on the vehicle, and tuning track circuits. In the United Kingdom, many classes of DMUs are required to be equipped with a Track Circuit Assistor (TCA), a vehicle-borne device that electrically assists the shunting of DC track circuits. Robust planning that takes into account capital costs associated with vehicles, facilities, and train control along with lifecycle operating costs can help in identifying the tradeoffs associated with any fleet plan. For many services, optimal fleet planning may result in a combination of MU and locomotive hauled consists Head End Power This section will provide a brief overview of Head End Power practices in North America that are most commonly used for revenue, common-carrier service. The focus is on the characteristics and attributes that affect capital costs, operating costs, and service performance Definition APTA maintains a series of recommended practice documents defining Head End Power as provided by locomotives, wayside sources, as it is used by passenger cars, and the performance requirements and specifications of hardware. APTA defines Head End Power (HEP) as: A system by which 480 VAC 3-phase electrical power, to operate auxiliaries, is provided to railroad vehicles from a central source via a trainline system. The power source can be a locomotive (hence Head End ), power car, or wayside source (4).

7 7 The use of 480 VAC 3-phase electrical power is widely used, however it is not universal. The Greater Toronto Transit Authority, operator of commuter rail service for the Greater Toronto Area under the service name GO Transit, uses 575 VAC 3-phase power for their service. In the recent past, DC power was used for HEP for commuter coaches. HEP is colloquially referred to as Hotel Power to differentiate it from power produced for locomotive traction Industry Recommended Practices APTA has published three Recommended Practice documents addressing topics relating to HEP: 14. APTA PR-E-RP , Recommended Practice for Head End Power Source Characteristics. Abstract: This recommended Practice defines the characteristics necessary on new equipment for head end power (HEP) sources, including diesel-driven alternators, inverters and utility-supplied wayside power. The HEP source is comprised of power source, switchgear, control system (incorporating trainline complete functions) and connections to vehicle HEP trainline(s) (5). 15. APTA PR-E-RP , Recommended Practice for 480 VAC Head End Power System Abstract: This document defines the recommended practices for a Head End Power (HEP) system, including hardware component functional requirements, transmission, power distribution and load properties for use on new locomotivehauled passenger vehicles. Single bus and split bus forms are described to accommodate intercity and commuter type operations (6). 17. APTA PR-E-RP , Recommended Practice for 480 VAC Head End Power Jumper and Receptacle Hardware Abstract: This document defines the recommended practices for Head End Power (HEP) jumper/ receptacle hardware (7). Anyone working with HEP or planning a HEP installation should also search for any recommended practices, regulations, and safety rules pertaining to HEP that are specific to the locations, properties, and jurisdiction they are working on/in/around. Safety First!

8 HEP Power Requirements A detailed study of in-service HEP demand in kilowatts has yet to be published; however, service operators may maintain their own internal figures for planning and evaluation purposes. A manufacturer of wayside power hardware provides the following estimates on power requirements on a per-car basis: Open window coach (no HVAC) lighting and other appliances: 1 kw Coach equipped per Amtrak configuration: 20-40kW depending on climatic conditions, with higher ambient temperatures increasing load demands. Business or Office Car (sleeping car and limited food service capabilities): 50kW Dining Car (max load while cooking food and serving passengers): 100kW Dome Car with food service: 130kW Full-Length Dome Car with extensive food service: approximately 150kW The maximum capacity of the 480 VAC 3-phase power, is estimated to be 1,200 kw (8) Sources of HEP APTA identifies four sources of HEP (9): Alternator driven from locomotive traction prime mover Alternator driven from exclusive (stand-alone) engine Locomotive inverter (driven by prime mover) Wayside power (used in yards and terminals) This section will focus on HEP produced by the locomotive and on wayside power. However, there are other sources of HEP not addressed by APTA s recommended practice that have niche applications. HEP power cars (cars that have a self-contained diesel generator and alternator) are widely used on railroad office-car trains, tourist trains, and rural lifeline passenger trains hauled by freight locomotives. They are also used in a limited number of revenue service passenger operations (such as on articulated train sets built by Talgo used on a limited number of intercity passenger corridors in the US) where it has been deemed advantageous to avoid a single point of failure. In the recent past, some small commuter rail services used generator-equipped cars to provide passenger service from a pool of locomotives also assigned to freight service. Additionally, most railroad office cars have self-contained generator sets capable of powering a single car or multiple cars.

9 9 With limited exceptions, HEP provided by the locomotive or through a stand-alone generator (on a car or locomotive) lacks the capability to synchronize across multiple units. On a multiple-unit locomotive consist, only one locomotive will be providing HEP with other locomotives being dedicated to providing traction power a HEP from Locomotive Traction Prime Mover Example locomotive types: F40PH, F40PH-2, F40PHM-2, F40PH-2D, The widespread adoption of HEP by intercity and commuter railroads in the 1970s and 1980s was facilitated, in part, by EMD s F40PH locomotive. Introduced in 1977, the F40PH (and variants) became a symbol of passenger service in North America. With over 400 units produced between 1977 and 1989, these locomotives were used throughout the United States and Canada. While many units have been retired and scrapped, others continue to provide a significant part of service for many large commuter and intercity passenger rail operations. Moreover, several units have been regeared to enable them to be used by short line and regional railroads in both passenger and freight service. The F40PH produces HEP from a generator driven by the prime-mover. When producing HEP (as selected by the engineer in Normal mode) the prime mover operates at a constant speed of 893 RPM (or throttle notch 8). The load on the prime mover is determined by two factors. Increasing HEP demand will increase load on the prime mover, up to the maximum output of the HEP generator. The throttle controls the excitation of the main generator. This increases power to the traction motors and load on the prime-mover. The prime-mover s mechanical governor maintains a constant speed under varying load conditions by adjusting the amount of fuel supplied to the primemover. An F40PH operating in MU with another locomotive that is providing HEP (or operating in a service where HEP is not required) will be set up to operate in the HEP isolate mode. In this mode, the throttle will directly control the prime-mover speed using a conventional throttle notch RPM sequence and HEP will not be produced. Providing HEP from a prime-mover driven alternator is attractive because of its mechanical simplicity and the durability of these appliances. However, there is a tradeoff in that the prime mover must run at a high constant speed. The fuel consumption associated with maintaining HEP even at periods of low demand, along with a desire to minimize engine noise and emissions around station and terminal areas motivated many operators to retrofit their F40PH units with stand-alone engines. An additional drawback for HEP produced via a locomotive driven prime mover is that the kw output for HEP comes directly at the expense of power that is available to the traction motors. The conversion of horsepower (HP) to Kilowatts is calculated using the conversion factor of.746kw to 1HP. An example of this calculation is shown below.

10 10 For a train pulled by 1 F40PH, producing 3000HP, with a consist of 4 coaches assumed to be demanding 30kW each and 1 dining car assumed to be demand 100kW (for a total of 220kW) HP will be needed to produce the necessary HEP leaving HP available for traction b Alternator Driven from Exclusive (stand-alone) Engine Example Locomotive Types: F40PHCAT, F40PHM-2C, F59PHI, MP36, MP40, BL20GH, BL36PH, GP40TC, a variety of locomotives remanufactured from GP40 locomotives. Producing HEP from a stand-alone engine is widely practiced. The first HEP equipped locomotives (entering service in the early 1960s) were equipped with stand-alone engines and many F40PH locomotives (and variants of this model) have been rebuilt with standalone engines as well. The main advantage with this strategy is that the stand-alone engine can run independently of the prime mover. This may reduce fuel consumption by allowing the prime mover to operate across all throttle notches when running or to be idled or shutdown at terminals. Additionally, it means that the locomotive s tractive effort will be unaffected by HEP demand. The use of a stand-alone engine also provides some redundancy as HEP can continue even if there is a failure of the prime mover that prevents the train from moving. However, this strategy comes with a tradeoff in that the stand-alone engine has its own its own maintenance schedule, servicing practices, and parts requirements that differ from that of a locomotive prime mover. Maintaining stand-alone engine introduces another system that shop forces will have to master and incorporate into maintenance schedules c Locomotive Inverter Example locomotive types: P32AC-DM, P42DC, PL42AC, HSP46, SC-44, F-125 An inverter (an appliance that converts DC power to AC) provides an alternative way to obtain HEP from the prime mover. The predominant design for locomotives using inverters is for the prime-mover to drive an alternator that produces AC power. Power from the alternator is rectified to DC. This DC power is then fed to a bus bar (often referred to as a DC Link) that feeds inverters. The inverter converts power from the DC link to HEP power. The use of a DC link also facilitates capturing power that is created by dynamic braking and using it for propulsion or HEP. Additional inverters may be used to provide AC power for traction motors on locomotives using AC traction motors. Some manufacturers have used identical inverters for HEP and traction power, providing for limp home capability should one inverter fail in service. The power regulating function of the mechanical governor is replaced by microprocessor control that controls the prime mover based on a combination of throttle position and HEP demand to ensure that there is sufficient power available on the DC link for all

11 11 locomotive functions. The microprocessor regulates DC voltage by controlling the excitation of the alternator and fuel injection. The HEP inverter can produce 480v 3- phase power from a range of DC voltages, depending on load condition. This allows the prime mover to operate over a wider range of speeds (between throttle notches 4 and 8 on many locomotives), saving fuel and reducing noise d Wayside Power Using wayside power to provide HEP at terminals and yards can provide a means to power passenger cars independent of a locomotive, potentially offering fuel savings and flexibility in equipment assignments. Alternate terms for wayside power include hotel power, shore power, and standby power. Wayside power is the preferred term for railroad applications. AREMA Manual Chapter 6, Part 8, Design Criteria for Passenger Stations contains additional information on design and hardware considerations for providing wayside power at stations and terminals, including wayside provision of trainline air to operate air-dependent passenger car systems Assessing the Costs and Benefits of Wayside Power relative to HEP Provided by Locomotives Wayside power offers an advantage to operators in reducing fuel consumption by allowing a locomotive and/or stand-alone HEP generator to be shut down completely between runs. This practice offers environmental advantages in reducing local emissions around terminals and yards and reducing ambient noise around terminals and shops. In these ways, the use of wayside power can forestall the mandate of other mitigation measures. Using wayside power in terminals and coach yards to maintain a constant interior temperature in winter operations can assist in preventing accumulation of ice and snow around below-floor electrical appliances, prevent freezing of water, toilets, air-operated doors. However, wayside power also has its tradeoffs. Purchasing and installing the hardware can be expensive. Power cabinets and associated appliances can be a target for vandalism. Additionally, labor costs in using the installed infrastructure may be high if the work is claimed by a craft vs. being handled by a utility worker or a contractor that is able to perform other tasks. AREMA Manual Chapter 6, Part 8, Design Criteria for Passenger Stations contains additional information that addresses these issues and how they may be mitigated.

12 Forecasting the Costs and Benefits of Installing Wayside Power The following method can be used to provide a pro-forma estimate of the cost savings in terms of fuel consumption that may be expected from installing wayside power. 1) Gather Information on Operating Practices: a) Calculate Power Usage by Locomotive Type: i) If an auxiliary generator is used to provide HEP, gather information on the amount of power that is used to power the trainset by kw. For an operating service, this may be done by establishing a sampling method to record HEP power output from trains currently idling at layover. For a new service, this could be done by using the HEP power requirements in this section multiplied by the amount of time that the train could be kept on power. ii) For HEP provided by the prime mover (via an alternator or an inverter), use manufacturer-provided data on fuel consumption by throttle notch/to calculate an estimation of fuel that is currently being used to provide HEP at the station and/or that is being used to idle the prime mover. iii) Note, power needs will vary depending on climate, the type of equipment being operated, and the amount of servicing that will be done inside the train at the location. It will be necessary to estimate costs for each season for locations with significant differences in climate conditions or operating practices. b) Review the amount of time that a train could be kept on power. Include arrival time and the time that would be needed by staff to connect/disconnect the train to power and shutdown / start-up the locomotive. The time needed to connect/disconnect can be very short depending on operating practices and staffing. Some North American commuter railroads have staff trained and positioned to routinely perform this task in less than a minute after trains arrive at a terminal. 2) Estimate the cost of fuel used at layover by multiplying the total gallons used by the price gallon for each layover time at a given location. This can be used as the basis for an annual total. 3) Estimate utility costs for providing wayside power. Information on power consumption by kw consumption calculated in step 1 can be used as a basis for calculating estimated electric utility costs. 4) Estimate the cost of additional labor hours and/or positions needed to connect/disconnect the rolling stock from wayside power infrastructure should also be assessed.

13 13 5) Calculate the total cost difference by subtracting the sum of utility costs of wayside power and labor costs from the total value of fuel savings. 6) The gallons of diesel saved calculated in step 2 can be multiplied by 22.2 to produce an estimate of pounds of CO2 saved by wayside power (10). Other emissions factors (e.g. SOx, NOx, etc.) will depend on emissions factor data provided by the manufacturer. The results of a cost/benefit analysis will depend greatly on fuel prices and electric utility costs. Price fluctuations may change the period over which the savings from reduced fuel consumption can match infrastructure costs Practical Considerations in Obtaining the Costs and Benefits of Wayside Power Installations Realizing the operating economy and economic potential of wayside power will depend on how its implementation is managed and how operating and financial data is tracked and analyzed. Front line managers may be reluctant to use wayside power to its greatest potential. There is a popular perception among mechanical forces regarding the relationship between shut/down restart events having a negative effect on locomotive reliability. It is often thought that, if a prime mover or auxiliary generator is shut down, a fault might occur when restarting it that could delay service. For operations that rely on contracted service providers, this perception could result in the continued idling of prime movers and stand alone generators, even when wayside power is available, in the interest of avoiding service disruption penalties. Additionally, contract revision may be necessary to align the cost saving interests of the service sponsor with the contract operator. In many traditional contracts, a contractor s compensation is pegged to the total cost of service. Reducing fuel consumption can have the result of reducing the contractor s total payment implicitly pitting the interests of the operating contractor against those of the service sponsor. In some cases, the consistent use of wayside power has only come through significant operating rule revisions, rule enforcement exercises, and contract revisions Considerations in Assessing Costs and Benefits after Installing Wayside Power The preceding section provided an overview of a range of technology alternatives and operating practices. In order to track the impact on fuel usage (a key driver of operating costs) it is important to identify the basis on which fuel usage is tracked by a given operation.

14 14 If fuel purchases are invoiced directly to an operator for a single operation (and not shared amongst other lines or services) then the cost savings will be realized immediately in reduced fuel payments. Tracking the impact of technology or operating practices can be more complicated if fuel costs are allocated across multiple lines or a large system. In places where allocation methods are used, ensuring that the cost savings flow back to the entity that sponsored the investment in wayside power requires identifying the allocations method and reaching an agreement on how to best assess and distribute fuel savings that reflects changes in appliances or operating practices. In locations where multiple lines are supported from a single fueling point, train miles or car miles are often used as a basis for dividing fuel usage. Other methods may use a train performance calculation as the basis for allocating shared fuel costs. A notable allocation method is Amtrak s Diesel Power Usage Factor (DPUF), which uses train-miles, train weight, route profile, running time, and idle time to allocate fuel usage to individual lines or services that share common fueling points (11). 1. Next Generation Corridor Equipment Committee. Vehicle Specifications. American Association of State Highway and Transportation Officials, Online Next Generation Corridor Equipment Committee, and Amtrak, Mechanical Department Bureau of Rolling Stock Engineering. Specification for Diesel- Electric Passenger Locomotives, PRIIA Specification No Revision A. Release Date July 10, 2012., p. 98. Section 6.5 Crash Energy Management (CEM). 3. Passenger Rail Equipment Safety Standards Task Force, American Public Transportation Association. 16. APTA PR-E-RP Recommended Practice for 27-Point Control and Communication Trainlines for Locomotives and Locomotive-Hauled Equipment. Edited March 22, Online Passenger Rail Equipment Safety Standards Task Force, American Public Transportation Association. 15. APTA PR-E-RP Recommended Practice for 480 VAC Head End Power System. Edited March 22, Section Definitions, p Online Passenger Rail Equipment Safety Standards Task Force, American Public Transportation Association. 14. APTA PR-E-RP , Recommended Practice for Head End Power Source Characteristics. Edited March 22, Online.

15 15 6. Passenger Rail Equipment Safety Standards Task Force, American Public Transportation Association. 15. APTA PR-E-RP Recommended Practice for 480 VAC Head End Power System. Edited March 22, Online Passenger Rail Equipment Safety Standards Task Force, American Public Transportation Association. 17. APTA PR-E-RP , Recommended Practice for 480 VAC Head End Power Jumper and Receptacle Hardware. Edited March 22, Online. PR-E-RP pdf. 8. Northwest Rail Electric Inc. Typical HEP Configurations. Online Passenger Rail Equipment Safety Standards Task Force, American Public Transportation Association. 14. APTA PR-E-RP , Recommended Practice for Head End Power Source Characteristics. Edited March 22, Section Power sources, p Online United States Environmental Protection Agency. (2005). Emission Facts: Average Carbon Dioxide Emissions Resulting from Gasoline and Diesel Fuel. Washington DC. 11. Federal Railroad Administration United States Department of Transportation, John A. Volpe National Transportation Systems Center United States Department of Transportation. Update on the Methodology for Amtrak Cost Accounting Amtrak Performance Tracking (APT). Volume 2, Appendices A F. April 22, p. D-16. Online.