Editing Grand Central Terminal (section)

==== Power and heating plants ====
[[File:GCT M42 Basement-Rotary-Untapped New York-Michelle Young.jpg|thumb|alt=A large piece of electrical equipment in the terminal basement|[[Rotary converter]] relics in the [[M42 (sub-basement)|M42 basement]]]]
Grand Central Terminal contains an underground [[sub-basement]] known as [[M42 (sub-basement)|M42]]. Its [[electrical substation]] is divided into substation 1T, which provides {{Convert|16,500|kW|}} for third-rail power, and substation 1L, which provides {{Convert|8000|kW|}} for other lighting and power.<ref name="IEEE-PES" /> The substation—the world's largest at the time—was built about {{Convert|100|ft|m}} under the Graybar Building at a cost of $3 million, and opened February 16, 1930.<ref name="IEEE-PES" /><ref>{{cite news|url=https://www.nytimes.com/1930/02/16/archives/huge-power-plant-100-feet-under-city-biggest-substation-in-world.html|title=Huge Power Plant 100 Feet Under City – Biggest Substation in World Moved Into Bedrock Under Grand Central Terminal – Service Never Cut Off – $3,000,000 System Ran Trains While Being Moved to Make Way for New Waldorf|date=February 16, 1930|website=The New York Times |issn=0362-4331|access-date=December 26, 2018|archive-date=December 27, 2018|archive-url=https://web.archive.org/web/20181227084742/https://www.nytimes.com/1930/02/16/archives/huge-power-plant-100-feet-under-city-biggest-substation-in-world.html|url-status=live}}</ref> It occupies a four-story space with an area of {{Convert|250|by|50|ft|m}}.<ref name="IEEE-PES" /><ref name="RN p. 157" />