A 1/2 HP garage door opener draws about 875 watts while the door moves (roughly 400-1,000 W) and can surge to about 2,350 W at start. It only runs a few minutes a day, so daily energy use is small.
- Running watts
- 875 WTypical; 400–1,000 W across models
- Starting watts
- 2,350 WGenerac's chart lists about 2,350 W to start a 1/2 HP opener…
- Per day
- 0.15 kWh0.05 h of use
- Current
- 7.3 AAt 120 V while running
Figures checked against DOE, ENERGY STAR and manufacturer data on . Your model's label is the final word.
Watts by model and setting
Most garage door opener models draw between 400 and 1,000 W while running; a typical one draws about 875 W. Motor runs only about 3 minutes a day (875 W x 0.05 h = about 0.04 kWh); most daily use is standby power for the receiver and sensors, about 1-15 W depending on age (around 0.1 kWh/day at 5 W).
- Motor size: 1/3, 1/2 and 3/4 HP-equivalent models
- AC chain-drive motors draw more and surge harder than DC belt-drive motors
- Door weight, spring balance and track condition change the motor load
- Built-in lights add up to 100 W per socket on older models; LED lights add little
- Standby draw ranges from about 1 W on newer models to 14 W or more on older ones
Running a garage door opener on a generator or power station
- Generator: at least 875 running watts and 3,225 starting watts (running plus the 2,350 W start surge, the cautious way to size it). Check both numbers on the spec sheet. A generator rated 3,500 W or more covers it with room to spare.
- Power station: continuous output of at least 875 W and a surge rating that covers about 2,350 W. Pure sine wave output is the safe choice for motors and electronics.
| Power station capacity | Estimated runtime |
|---|---|
| 500 Wh | 0.5 h |
| 1,000 Wh | 1 h |
| 2,000 Wh | 1.9 h |
| 3,000 Wh | 2.9 h |
Based on 875 W average draw and 85% usable capacity.
- You rarely need to power an opener in an outage: every opener has a manual release cord so you can open the door by hand
- Many newer DC openers have optional or built-in battery backup that gives a number of cycles without grid power
- If you do power one, a power station with pure sine wave output and a surge rating above about 2,400 W covers most 1/2 HP AC models
- Run a gas generator outdoors only, at least 20 feet from doors, windows and vents; carbon monoxide from generators kills. Use heavy-duty extension cords or a professionally installed transfer switch, never backfeed a home outlet.
Add it to the generator calculator
Questions people ask
Can a portable power station open my garage door?
Usually yes, if its surge rating covers the motor start (up to about 2,350 W for a 1/2 HP AC opener). Each open or close uses only a few watt-hours of battery.
How much electricity does a garage door opener use per year?
Mostly standby: older units drawing around 10-14 W use over 100 kWh a year, while newer models at about 1 W use under 10 kWh plus a little for actual door cycles.