How Long Will a Power Station Run My House? (2026 Runtime Tables)
Affiliate disclosure: This post contains affiliate links. As an Amazon Associate I earn from qualifying purchases. Product picks were chosen on the merits — no brand pays for placement.
How long will a power station run my house? There is no single answer, because it depends entirely on what you mean by “run.” Keeping a fridge and some lights alive is a very different job from powering the house as normal. This guide gives you real runtime numbers for both, and the arithmetic to work out your own.
The short answer
Running essentials only — fridge, lights, internet, phones — a 2 kWh unit lasts roughly 6–7 hours and a 4 kWh unit roughly 12–14. Running the house as normal including air conditioning, any portable unit lasts well under two hours. The gap between those two scenarios is the entire subject.
Runtime by capacity and load
These figures assume a 320 W essentials load — fridge cycling at 150 W, freezer at 60 W, router at 15 W, lights at 35 W, device charging at 15 W, plus margin — and include the roughly 15% real-world loss you should always subtract.
| Capacity | Essentials (320 W) | Fridge only (150 W) | + Window AC (900 W) |
|---|---|---|---|
| 768 Wh | ~2 hours | ~4.5 hours | ~40 min |
| 1,056 Wh | ~2.8 hours | ~6 hours | ~55 min |
| 2,048 Wh | ~5.5 hours | ~11.5 hours | ~1.8 hours |
| 3,840 Wh | ~10 hours | ~21 hours | ~3.5 hours |
| 4,096 Wh | ~11 hours | ~23 hours | ~3.8 hours |
Two things jump out. Dropping to fridge-only roughly doubles your runtime, which is why load discipline matters more than capacity during a long outage. And air conditioning collapses everything — even the largest portable unit gives you an afternoon, not a day.
Work out your own number
To answer “how long will a power station run my house” for your own setup, take three steps. First, add up the average watts of everything that must run. Second, divide your unit’s watt-hours by that number. Third, multiply by 0.85 for real-world losses.
Worked example: a 2,048 Wh unit running 320 W of essentials gives 2,048 ÷ 320 = 6.4 hours, then × 0.85 = about 5.4 hours. Full method in watt-hours explained.
Use average draw rather than the number on the appliance label. A fridge label shows peak compressor draw, but it only runs about 30% of the time. Divide the annual kWh figure on the yellow Energy Guide sticker by 8,760 to get a true average.
How to stretch it during an outage
Pre-chill before the outage. If a storm is forecast, turn the fridge and freezer to their coldest setting. The thermal buffer buys you hours later.
Fill empty freezer space with water bottles. Frozen mass holds cold and reduces compressor cycling, which directly reduces watt-hours consumed.
Open the fridge as little as possible. Every opening triggers a compressor cycle costing 20–40 Wh. Planning meals so you open it once every four hours rather than hourly is worth real runtime.
Charge devices from USB ports directly. Skipping the inverter saves roughly 15% versus using an AC wall adapter.
Deploy solar the moment it is safe. Even overcast panels return 20–40% of rated output, and post-storm skies usually clear while the outage continues.
Matching capacity to outage length
Short outages, a few hours: 1 kWh is plenty. The Anker SOLIX C1000 Gen 2 covers the fridge and recharges in 49 minutes when power returns.
Overnight: 2 kWh. The Bluetti AC200L runs essentials through the night with margin.
Full day or more: 4 kWh plus solar. The EcoFlow Delta Pro 3, or the Anker SOLIX F3800 Plus if you need 240V for a well pump.
Multi-day: battery alone will not do it. You need expansion capacity plus 400 W or more of solar for daily recharge. See the home backup master guide.
Frequently asked questions
How long will a power station run my house if I want everything on?
Not as normal, and not for long. Whole-home including air conditioning is a 20 kWh-plus proposition that usually means a permanent installation. Portable units are built for essentials-plus backup, which for most households is what actually matters.
Why is my real runtime shorter than the calculation?
Inverter conversion costs 10–15%, compressor startups spike consumption, and cold reduces available capacity. There may also be loads you forgot — standby electronics, a garage freezer, a sump pump cycling quietly.
Does running at high load drain it faster than the maths suggests?
Slightly, yes. Inverters are less efficient near their rated ceiling, and heavy draw generates heat that costs a little more energy. Expect marginally worse than calculated when running close to maximum output.
How much solar do I need to keep up with essentials?
A 320 W continuous load consumes about 7,700 Wh per day. Covering that needs roughly 1,600–2,000 W of panels in good sun, which is a serious array. A 400 W array meaningfully extends your runtime but will not fully offset a constant essentials load.
Last updated: July 18, 2026. Runtime figures are calculated estimates including a 15% efficiency allowance; actual results vary with temperature, appliance age, and load profile.
