How much electricity does a TV use overnight?
A modern TV left on overnight draws somewhere between 30 and 150 watts depending on its size — a 32" set uses around 32W, while a 65" set draws closer to 100W. Left on for five hours after you fall asleep, five nights a week, a 65" TV uses about 182 kWh a year. At the US average residential rate of 17.65¢/kWh, that's roughly $32 a year — not nothing, but not the whole story either.
How much does it cost to leave a TV on all night?
For a single TV, the honest answer is: not very much. A 32" TV run 3 hours a night costs about $6 a year. A 65" TV run 5 hours a night costs about $32. Add a couple of streaming sticks, a soundbar, or a game console left idle-on — at 90W, consoles are a bigger hidden load than most people expect, adding roughly $29 a year on their own — and the number climbs, but device electricity alone rarely justifies a subscription by itself. The bigger lever, for most households, is the thermostat.
Does turning down the thermostat at night actually save money?
Yes, and the effect is larger than any single device. The Department of Energy estimates that a 7–10°F overnight setback for about eight hours saves roughly 10% on heating and cooling costs — since heating and cooling is close to half of a typical household's energy bill, that 10% is worth far more than switching off a TV. A more modest, realistic setback of 3–4°F saves proportionally less, and homes with heat pumps see roughly half the benefit, because the auxiliary resistance heat that kicks in on recovery erodes some of the saving. This calculator applies that discount automatically when you select a heat pump.
How much CO₂ does leaving a TV on produce?
Using the EPA's national grid average of 0.394 kg CO₂ per kWh, a 65" TV run overnight produces roughly 72 kg of CO₂ a year from electricity alone — equivalent to about 183 miles of driving. It's a real number, but it's a modest one: about 1% of a single person's annual carbon footprint. This calculator uses the US average grid intensity rather than a state-specific figure, since a reliable free source for state-by-state carbon intensity wasn't available for this version — a household on a cleaner regional grid would see a somewhat lower true figure, and one on a coal-heavy grid somewhat higher.
Figures throughout this page are estimates based on published wattage figures, EIA state electricity and gas rates, and EPA emissions factors, using the assumptions shown in the calculator above. Actual savings vary by device, usage and local electricity rates.