New York City Mayor Zohran Mamdani announced a feasibility study with the MTA focused on subway heat beneath City Hall. The study will examine whether heat from Brooklyn Bridge-City Hall station can warm nearby municipal buildings during winter. It drew attention because the proposal links subway cooling with winter heating through an underground thermal system.
Mamdani began by describing the problem the project aims to address. He said subway platforms become “underground saunas” during August. Brooklyn Bridge-City Hall, he added, becomes one of the city’s hottest stations during summer.
The study will examine whether that accumulated heat can serve another purpose once temperatures fall. Mamdani said the city wants to use it to heat the municipal campus above the station.
Mamdani then outlined how the proposed system could work. Boreholes would extend between 500 and 600 feet underground beneath the area. He said it could reduce steam consumption while lowering heating costs for the city.
He closed by linking the proposal to broader station improvements. Mamdani said the work would make the stations “cool again” while making “what is old new again.”
Zohran Mamdani’s Subway Heat Plan Draws Questions Over Cost and Feasibility
The proposal drew competing reactions over whether the thermal system could work as envisioned and what pursuing it could ultimately cost.
One X user questioned the central concept, writing, “So he is he moving heat from summer to winter, good trick. Don’t need a study for that just show us how you store heat for 6 months.” Another asked, “I’d like to see this feasibility study and who is bidding on the project or is this going to be an endless gov sponsored money pit?”
A separate response focused on implementation and oversight: “Not a bad idea, however it will be expensive and I don’t trust your administration to oversee a project like that.”
Others welcomed the idea. One response stated, “Now this is the sort of government action I want to see – forward-thinking and innovative.” Another wrote, “I know some folks will find a way to knock anything Zohran tries. But props to him for trying something new in America”
Mamdani described the proposal as a feasibility study rather than a finalized system and did not provide a projected cost in the remarks shown. Whether the idea ultimately moves forward remains to be seen, but it has already prompted plenty of discussion among New Yorkers about both its practicality and its potential cost.
