1. Home
2. Environment
3. Environmental Programs
4. ecoTRANSPORT
5. ecoFREIGHT
6. Rail
7. Installation of Auxiliary Power Units on Locomotive

Installation of Auxiliary Power Units on Locomotive

The analysis and conclusions contained in this case study are those of the authors alone and do not necessarily represent the point of view of the Government of Canada.

Organization
Huron Central Railway

Major Findings
Using auxiliary power units instead of main locomotive engines to warm the engines for periods below 5^oC saved at least 19,000 L per season per GP38 locomotive and reduced CO₂ emissions by about 53 tonnes.

Project Timeline
November 2005 to June 2006

Please note that some figures such cost savings on fuel are based on data from the period that this project took place.

Introduction

The U.S. Environmental Protection Agency (EPA) estimates that, on average, railway locomotives are inactive 40% of every day. In cold climates, idling the main engine during inactive periods maintains cab temperature and protects the engine cooling system from freezing. This practice consumes fuel and releases emissions.

With a financial contribution from Transport Canada's Freight Incentives Program, the Huron Central Railway acquired auxiliary power units (APUs) to reduce idling in locomotives. This project took place from November 2005 to June 2006.

Project Description

The APUs were linked to the main systems to provide heating for the main engine and maintain battery charge, brake pressure and cab comfort, as required.

Data from the APU can be sent via satellite to give real-time indication of idling time and fuel savings resulting from using APUs instead of the main engine, since they use about 10% of the fuel required to operate the main engine. While a GP 38 locomotive consumes about 15.2 L (4 US gallons) per hour, an APU consumes about 1.9 L (0.5 US gallons). The use of the APUs should result in savings of 13.3 L (3.5 US gallons) per hour.

For Huron Central's operating climate, APUs were expected to provide fuel, emissions savings and engine wear savings in December, January, February and March - months where the overnight temperature is likely to fall below 5^oC. When the temperature is above 5^oC, Huron Central operating policy requires inactive locomotives to be shut down completely.

Project Goals and Objectives

The purpose of this project was to confirm the effectiveness of APUs for reducing fuel use and emissions of idling railroad locomotives during cold weather. The K9®APU tested is a diesel engine genset that consists of a 48 HP, 1800 rpm, 4 cylinder turbocharged engine that produces 16 kW, 240/120VAC, 60Hz power, and an engine shutdown timer. The system protects the main locomotive engine during shutdown times by monitoring and maintaining the lube oil and water temperatures, battery charge, brake pressure, and cab comfort as required.

Project Methodology

Huron Central Railway installed and monitored the performance of APUs on two locomotives serving its Sault Ste. Marie - Sudbury route. The model K9® APUs manufactured by EcoTrans were installed on General Motors EMD GP38 locomotives (2,000 hp).

Fuel consumption was measured for each locomotive at each refuelling. Emission factors provided by the Railway Association of Canada were used to calculate the emissions savings resulting from fuel savings.

Results

APUs effectively reduced fuel consumption and emissions for the months of January, February, March, and to a lesser extent, April and May. No data is available for November and December, but it could be expected that the use of APUs would result in some fuel savings for these months.

Over most of one winter during the project, there were over 22,000 hours of overnight idling hours when the main engines were converted to auxiliary power. The resulting fuel savings per locomotive are shown in Table 1. During the project period, no maintenance problems were reported for the APU.

   Table 1 Fuel savings by month for one GP38 locomotive

	January	February	March	April	May	Total
Days with lows below 5oC (2-year average)	31	28	29	11	5	104
Overnight hours (14 hours per day)	434	392	406	154	70	1,386
Main engine fuel use (15.2 L/hour)	6,597	5,958	6,171	2,341	1,064	22,131
APU fuel use (1.9 L/hour)	825	745	771	293	133	2,766
Savings per locomotive (L)	5,772	5,214	5,400	2,048	931	19,365

The fuel savings translate to 52.9 fewer tonnes of CO₂ emissions (Table 2).

   Table 2 Emission reductions based on 19,365 L of diesel
for one GP38 locomotive

Emissions	Reduction
Carbon dioxide (CO2) (2.73 tonnes per 1000 L)	52.9 tonnes
Methane CH4 (0.00015 kg per L)	2.9 kg
Nitrogen oxide (NOx) (0.0011 tonnes per 1000 L)	0.02 kg

Conclusion

Using main locomotive engines to maintain engine heat during overnight idling hours is expensive in terms of fuel consumption, greenhouse gas emissions, and engine wear. The testing of EcoTrans K9® APUs for periods below 5^oC saved at least 19,000 L per season per GP38 locomotive and reduced CO₂ emissions by at least 53 tonnes.

Additional Information

• Huron Central Railway
• Teleflex EcoTrans Inc.
• Railway Association of Canada

Alternative Format

The following document is available for downloading or viewing:

PDF version (Size: 150 KB)

Date modified:

2012-02-08

Primary navigation