Railroad electrification in the United States

Railroad electrification in the United States began at the turn of the 20th century, with many private railroad companies seeking to electrify portions of their network. The introduction of electrification by various companies led to the development of multiple divergent electrification systems in different geographical areas, few of which were interconnected. Despite this divergence in method, most of these systems shared a small number of common reasons for electrification.

Mainline railroad electrification in the United States is quite rare in comparison to most European or East Asian rail networks, with less than 1% of mainline trackage in the country being electrified. Most of the systems discussed in this article are either no longer electrified, or are now part of the Northeast Corridor and Keystone Corridor systems used by Amtrak and several commuter rail lines. A few isolated systems, operated exclusively for hauling coal from mines to power plants, also retain their electrification. Most mass transit, streetcar, and interurban systems were electrified very early in their existence (many from the beginning) but are not within the scope of this article.

Opposition to electrification by the major Class I railroads for its cost and perceived lack of benefit forms a large part of the reason for its relative lack in the US. For example, the Association of American Railroads opposes electrification due to its high capital costs. Opponents of electrification also argue that since the entire United States railroad network contributes only 0.56% of the nation's greenhouse gas emissions, electrification would be of negligible benefit to the environment.