China's Power Department Refutes 24‑Hour Air‑Conditioner Savings Claim

Online posts in mainland China claimed that keeping an air‑conditioner running 24 hours a day reduces electricity bills, citing personal experiments that reported monthly costs as low as ¥118 versus higher costs for intermittent use. The State Grid Beijing Electric Power Company responded that the claim has no factual basis. It advised that for brief absences (under an hour) users can raise the thermostat by 1–2 °C instead of turning the unit off, which saves more energy than frequent on/off cycles.

The power department also recommended four practical measures: use a fan together with the air‑conditioner to lower perceived temperature by 2–3 °C; keep curtains closed to block strong sunlight; set the temperature in the “golden zone” of 26–28 °C (daytime 25–26 °C for comfort, night 27–28 °C to avoid over‑cooling); and, when returning home, start at 23 °C for rapid cooling then raise to 26 °C after about 30 minutes. The advice was echoed in Hong Kong media as the city experiences a heat wave and residents seek efficient cooling.