New York City officials are launching a study to explore harnessing the intense heat generated on subway platforms and redirecting it to warm nearby city buildings.
The initiative, announced by Mayor Zohran Mamdani and MTA Chair and CEO Janno Lieber, will focus on the Brooklyn Bridge-City Hall and Chambers Street subway stations, known for their extreme summer temperatures.
This project aims to install a thermal energy network (TEN), a system that captures, stores, and redirects heat. The goal is to cool the subway platforms, which can reach temperatures as high as 96 degrees Fahrenheit, and use that captured thermal energy to heat municipal buildings during colder months. Buildings potentially slated to benefit include City Hall, the David Dinkins municipal building, Tweed Courthouse, and Surrogate’s Court.
A contract for the feasibility study is expected to be awarded by the fall, with design work anticipated in early 2027. If successful, this would mark the first application of such a thermal energy network within a U.S. transit system.
Lieber noted that similar technologies are already in use elsewhere in the city, citing St. Patrick's Cathedral as an example, and emphasized the potential for a mutually beneficial outcome.
The project aligns with broader efforts to improve the city's infrastructure and combat climate change. The Chambers Street station, in particular, is scheduled for a modernization project, funded by congestion pricing tolls, which will address its dilapidated condition. This modernization includes repairing tiles, replacing fixtures, fixing leaks, and upgrading lighting, all of which could integrate with the thermal energy network installation.
The proposed system would involve drilling geothermal boreholes 500 to 600 feet underground, beneath an abandoned section of the Chambers Street platform to minimize passenger disruption. Radiant cooling technology would be employed to absorb heat from the platforms, transferring it through pipes to the boreholes for storage and later use.