Concept Definition of a Zero Emissions Boost Locomotive for Regional Passenger Rail

The advantages of rail electrification have been demonstrated worldwide, yielding reductions in energy costs, locomotive maintenance, polluting emissions and noise; but these benefits are compromised by the high capital costs of the overhead catenary infrastructure. Both the significant initial investment and loss of the operational flexibility, relative to conventional diesel-electric locomotive solutions, impede consideration of rail electrification in many applications. Described in this paper is a way to retain the best features of both dedicated electric and conventional diesel-electric for powering regional and commuter rail services characterized by frequent and energy-intensive stop and go operations. The innovation is a ‘Zero Emissions Boost Locomotive’ (ZEBL), a new type of locomotive “B” unit that is coupled in a ‘plug and play’ manner behind a conventional diesel-electric locomotive. The ZEBL is an all-electric motorized unit containing a power pack of batteries and ultracapacitors providing energy-capture, storage and regeneration to boost train acceleration. The ZEBL provides an open platform that allows future expansion to incorporate new energy storage technology and grid connectivity through wireless power transfer (WPT) during station stops. Simulations indicate that adding a ZEBL to an existing commuter train boosts acceleration reducing trip time and allowing much longer trains, while its energy regeneration features significantly reduce fuel consumption, diesel emissions and wear and tear on the consumable braking components.