Four floors below one of Manhattan's most iconic office buildings, something strange happens every night. Machines silently freeze half a million pounds of water into ice, roughly three city buses' worth. By morning, the ice has melted, and the chilled water cools the building throughout the day. CBS News reported in June 2025 that this is how Eleven Madison Avenue keeps itself air-conditioned, based on interviews with the company that installed the system. A study conducted by the National Energy Assistance Directors Association and published in May 2025 revealed that the average summer household cooling bill in the United States for June through September was estimated to be $784. The same CBS report cited this figure as the highest summer average in the 12-year history of the organization's records on cooling expenses.
Meet the "ice battery"
