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Pick what you want to run and get the exact watt-hours and output watts to look for — or flip it around and see how long a power station will keep your gear going.
As an Amazon Associate we earn from qualifying purchases at no additional cost to you. Capacity tiers are general guides — always match the unit's output watts to your highest-draw appliance.
Sizing a power station comes down to two separate numbers that people often confuse. You need enough watt-hours (Wh) — the size of the battery — to run your gear for as long as you want, and enough output watts (W) — the strength of the inverter — to turn everything on at once. A huge battery with a weak inverter still can't start a microwave; a strong inverter with a tiny battery dies in minutes. The calculator above solves for both.
For each device, multiply its running watts × hours used, add them all up, then pad the total to cover real-world losses:
So if your devices need 600Wh of actual work, you should shop for roughly 600 × 1.15 × 1.25 ≈ 860Wh of rated capacity. That's exactly the math the tool runs for you.
Anything with a motor or compressor — fridges, pumps, power tools, air conditioners — briefly pulls a startup surge of 3–6× its running watts. A fridge that runs at 150W can spike past 1,000W for a split second when the compressor kicks on. If the station's surge rating can't cover that spike, it shuts off even though the battery is full. The calculator flags this and tells you the minimum output to look for.
Use these as ballpark figures — your actual device may differ, so check its label or measure it with an inexpensive plug-in watt meter.
| Appliance | Running watts | Startup surge |
|---|---|---|
| Phone charging | 10 W | none |
| Laptop | 60 W | none |
| Wi-Fi router + modem | 15 W | none |
| LED lights | 10 W | none |
| CPAP (no humidifier) | 40 W | none |
| Mini fridge | 60 W | ~180 W |
| Full-size refrigerator | 150 W | 600–1200 W |
| TV (50" LED) | 100 W | none |
| Microwave | 1000 W | ~1500 W |
| Coffee maker | 800 W | none |
| Space heater | 1500 W | none |
| Portable AC (8k BTU) | 1000 W | ~2200 W |
| Corded drill | 700 W | ~1500 W |
Phones, lights, a fan, and charging a laptop or camera sip power — a 300–500Wh unit covers a weekend. Add a 12V fridge and you'll want 1000Wh, plus a solar panel if you're out longer than a couple of days.
To keep a fridge, phones, Wi-Fi, and some lights going through a typical outage, target 1000–2000Wh and at least 1500–1800W output for the fridge surge. For multi-day outages, pair it with solar or a unit you can recharge from your car.
Turn off the heated humidifier and you're often under 40W — a 500Wh station can cover two nights. Use the machine's DC port if it has one to skip inverter losses entirely.
Running several appliances and recharging daily means 2000–3000Wh+ with an expandable battery and a high-output inverter. Size your solar to roughly replace your daily watt-hour total.