NYC Mayor Urges Residents to Set ACs to 78°F Amid Heat Wave and Grid Strain

New York City Mayor Zohran Mamdani posted on X on July 1, 2026, asking residents and businesses to set air conditioners to 78 degrees, turn off unused lights and electronics, and unplug devices to ease pressure on the power grid during an extreme heat wave expected to push temperatures above 100°F.[1][2] The official NYC.gov site confirmed the city is expanding emergency heat measures, including thermostat settings at 78°F in city buildings and encouraging conservation during peak demand.[3]

The appeal comes as New York faces documented grid vulnerabilities. The New York Independent System Operator (NYISO) has warned of the lowest reliability margins in years, projecting risks of shortfalls during multi-day heat waves of 95–98°F due to aging generation, plant retirements, and rising demand.[4][5] Similar concerns predate the current event, with reports highlighting thin reserves and potential localized blackouts as early as summer 2026.[6]

The measure has drawn criticism and online debate, with some linking it to broader energy policy choices such as the 2021 closure of the Indian Point nuclear plant.[7] Con Edison and other utilities have echoed calls for voluntary reductions to avoid outages.[8] This reflects a pattern of summer conservation requests tied to extreme weather and infrastructure constraints, extending beyond NYC to regional PJM and Mid-Atlantic grids under stress from high cooling loads.