MTA to lower subway platform temperatures, harness thermal energy in Lower Manhattan

New York Mayor Mamdani, Governor Hochul and the Metropolitan Transportation Authority (MTA) announced a partnership to study a Thermal Energy Network (TEN) in the Brooklyn Bridge-City Hall 4/5/6 and Chambers Street J/Z station complex. The project will explore how to combat extreme heat on subway platforms while capturing and recycling excess heat to warm nearby municipal buildings during the winter.

The project would be the first thermal energy network installed in a U.S. transit system. The announcement comes days after Governor Hochul and the MTA announced plans for a comprehensive renewal project at the Chambers Street station, which is among the oldest in the subway system.

Brooklyn Bridge-City Hall 4/5/6 is one of the hottest stations in the subway system, with average temperatures reaching 96 Fahrenheit during the summer months, in 2025. While the MTA prioritizes reliable service in the short-term to get customers on air-conditioned trains and spend less time on platforms, this study will help identify ways to reduce heat, improve rider comfort, and mitigate heat-related issues that can lead to service delays.

The revitalization of Chambers Street J/Z, which will rebuild structures, replace tiles, upgrade stairways and restore the station from top to bottom, is being funded through congestion pricing. The project provides the MTA and City with a unique opportunity to study TENs as a tool to cool subway platforms while capturing and reusing excess heat in nearby municipal buildings during the winter, lowering energy costs over the long term.

TENs, already in use at several hospitals and universities, move heat between buildings, significantly reducing reliance on fossil fuels. The MTA and City will assess the feasibility of using TENs and geothermal infrastructure to absorb, store and transport excess heat between subway stations and adjacent municipal buildings.

The initial feasibility study will help determine how much cooling can be achieved and the potential energy cost savings for the City. The proposed geothermal network would capture, store and redirect excess heat that accumulates in the Brooklyn Bridge-City Hall and Chambers Street station complex to municipal buildings. Radiant cooling technology would absorb heat from Brooklyn Bridge-City Hall platforms, and potentially Chamber Street as well, and transfer it through pipes to geothermal boreholes drilled beneath the abandoned center platform at Chambers Street. The excess heat could then be stored in the boreholes and used during colder months to heat nearby municipal buildings.

The study will be conducted in partnership with New York City Department of City Administrative Services (DCAS), the Mayor's Office of Climate and Environmental Justice, the Office of the Deputy Mayor for Operations and the MTA. The contract for the feasibility study is expected to be awarded this fall. Pending confirmation of geothermal feasibility, design work will begin in early 2027.

This initiative is part of the City and MTA's broader efforts to address the threat climate change poses to the future of the transit system, including the growing impacts of extreme heat. Radiant cooling, which can be 25 to 35% more energy efficient than traditional air conditioning, removes heat by circulating chilled water through panels on walls and ceiling or through tubing embedded in the floors, allowing cool surfaces to absorb heat directly.

The Chambers Street station is particularly well suited for the study because its abandoned center platform would allow the MTA to test technology without disrupting passenger areas. Brooklyn Bridge – City Hall also experiences significant heat in part because of heat generated by trains dwelling at the 6 line terminal.

The partnership with the MTA builds on the Mamdani administration's efforts to confront the climate crisis and build a greener, more resilient city. Earlier this year, the administration released its Urban Forest Plan, plotting a course toward 30% tree coverage citywide. As temperatures rise, expanded tree canopy will help reduce heat and protect New Yorkers for years to come. The administration is also making historic investments in renewable energy, including the construction of 130 solar installations on schools across New York City that will provide 27.5 megawatts of electricity. An additional 86 projects are in the pipeline and would add another 17.2 megawatts.

As part of the administration's mission to reduce citywide emissions, the City is also accelerating vehicle electrification. The administration has already surpassed 1,000 electric vehicles for law enforcement and is on track to fully electrify the Sanitation Department, Parks Department and DCAS enforcement fleets by 2030 — five years ahead of the timeline required by local law.

Source: MTA