Expands an existing federal program to let entities that provide commuter rail passenger transportation apply to carry out projects that develop and implement regenerative braking and energy storage technologies. This change makes commuter rail operators explicitly eligible to receive support under the referenced statutory authority for energy-saving and electrification-related projects.

The text only changes eligibility; it does not itself appropriate money or create new funding levels. Commuter rail agencies and authorities can now pursue grants or projects under that program to reduce energy use, recover braking energy, and deploy storage systems that can lower operating costs and emissions.