Steamy NYC subway air would be sucked out to cool stations, heat buildings under proposed plan

Hot air would be sucked out of New York City’s sweltering subway system to cool stations in summer and heat municipal offices during winter, under a plan that will be studied this year, authorities said Monday.

The study, of what are called thermal energy networks, will be conducted at Manhattan’s Chambers Street J/Z-Brooklyn Bridge-City Hall 4/5/6 station, and will examine whether it’s feasible to "capture, store and then transfer the excessive heat" to warm the Dinkins Municipal Building upstairs at 1 Centre St., the largest city-government office building in the world, according to Janno Lieber, head of the Metropolitan Transportation Authority, which runs the subways.

While already being used at St. Patrick’s Cathedral and the New York Botanical Garden and in Canada and Europe, "this technology has never been tested before in a transit system here in this country," Lieber said.

For the subways, the aim is to reduce underground temperatures by several degrees, he said, which would make a difference in the Chambers Street/Brooklyn-Bridge-City Hall station complex. The 4/5/6 platform is one of the "sweatiest" stations in the 472-station system, with average temperatures peaking at 96 degrees.

The study, said to cost about $800,000, will analyze how much cooler the stations can be and how much money could be saved, Lieber said Monday.

Mayor Zohran Mamdani, who joined Lieber on a disused platform, said that if successful, the excess heat from summer would heat nearby municipal buildings, such as City Hall, Surrogate's Court and the Department of Education.

"Anyone who has stood on a subway platform in August knows that our stations do not just get hot; they turn into underground saunas," Mamdani said.

Under the plan, heat would course through a system of circulating pumps and pipes drilled 500 to 600 feet underground. Radiant cooling, according to a news release, "removes heat by circulating chilled water through panels on walls and ceiling or through tubing embedded in the floors."

The MTA is looking to determine the feasibility of the plan by the end of the year, and design work could begin as early as next year. There is currently no cost estimate, according to MTA spokeswoman Laura Cala-Rauch.

By Matthew Chayes

matthew.chayes@newsday.comchayesmatthew

Matthew Chayes, a Newsday reporter since 2007, covers New York City.