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Power Outage Runtime Planner
Work out roughly how long your battery or power station could keep the important things running — and what to switch off first if it can't. Four short steps, nothing to sign up for, and every number stays in your browser.
Planning estimates only — not a performance guarantee.
Situation
STEP 1 / 4Step 1 of 4
How long do you need to cover?
Pick the situation closest to yours. You can change the hours afterward.
hours
Between 1 hour and two weeks. Longer plans get harder, not impossible.
Common questions
REFERENCE- How long will a 1000Wh power station last?
- It depends entirely on what you plug into it. After conversion losses, a 1000Wh unit typically delivers around 850Wh to your devices. That could be many nights of phone charging and a single LED lamp, or only a few hours of a full-size refrigerator. The planner adds up your own device list rather than guessing.
- How do I calculate watt-hours?
- Multiply a device's wattage by the hours you plan to use it. A 60W laptop for three hours is about 180Wh. For appliances that cycle on and off, such as a refrigerator, multiply again by the share of each hour the compressor actually runs.
- Can I run a refrigerator on a portable power station?
- Often yes for a limited period, but refrigerators vary substantially and draw a brief surge when the compressor starts. Check the label on your specific appliance and confirm your power station's continuous and surge output ratings, not just its capacity.
- Why is usable capacity lower than the advertised number?
- Converting stored energy into household AC power loses some of it, and real conditions such as temperature reduce it further. Planning with a conservative allowance is safer than assuming you get every advertised watt-hour.
- Can solar panels keep my battery topped up during an outage?
- Sometimes partly. A folding panel rarely produces its full advertised rating all day — shade, clouds, heat, angle, season, and window glass all reduce output. Treat solar as a bonus that may extend your plan, never as the thing that makes the plan work.
- Is this safe to use for medical equipment?
- No tool should be your only backup plan for life-sustaining equipment. Confirm backup power requirements with the device manufacturer and an appropriate healthcare professional, and never reduce medically necessary use to make a calculation fit.