A grant from the TIGGER Program will help the Alaska Railroad Corporation (ARRC) overhaul and retrofit three of its GP40 locomotives with emission-reduction kits and idle-reduction systems. These upgrades will bring the locomotive engines into compliance with Environmental Protection Agency (EPA) standards for lower greenhouse gas emissions and improved fuel efficiency.

The retrofit involves the installation of the following equipment:

1. New after-cooler equipment to improve coolant water flow (moving cooler air through the engine turbochargers and root blowers will reduce emissions)
2. New engine fuel injectors that will improve fuel-burning efficiency (thus reducing emissions)
3. New power assemblies designed to reduce engine-oil consumption, also known as blow-by (using less oil will reduce emissions)
4. Automatic engine start-stop idle-reduction system, manufactured by ZTR Control Systems, to turn off the engine when the locomotive is not in use or is sufficiently warmed up (turning off the engine when it is not needed will save fuel and reduce emissions).

This project will achieve sizeable emission reductions and fuel savings at modest costs. At $460,000 per locomotive, the budget includes overhaul activities (such as work on the locomotive engine, generator, auxiliary generator, and air compressor) and the purchase of emission-reduction kits manufactured to comply with Tier 0+ emission standards. Work on the project began in 2011 and will be completed by May 2013. The work will be accomplished primarily during the winter months when passenger service requirements are at a minimum and the locomotives can be conveniently rotated out of regular service.