How long will a power station run a fridge, furnace or router? 24-hour power plans
Real-world examples of using a 500, 1,000 or 2,000 Wh power station through a day without power: summer with the fridge, a winter evening with the heating, working from home. How to calculate, what the station itself uses and how much a solar panel adds.
In short
- Formula: hours ≈ capacity in Wh × 0.85 ÷ load in W. A 1,000 Wh station gives you about 850 Wh of usable energy.
- With 1,000 Wh you can run the router, phones, lights and the fridge for a few hours for a whole day. Or a gas furnace blower for a winter evening.
- The station's inverter itself draws 10–30 W while the AC outlets are on. Switch them off when not in use.
- A 200 W panel brings 600–1,000 Wh a day in summer; in winter, often less than a third of that.
Estimated runtime 0 hours
Total load 0 W
The load is higher than the output rating: the station will shut down. Pick fewer appliances or a stronger station.
Estimate assumes 85% efficiency. Real consumption varies by appliance; check the label or measure with a plug-in power meter.
A power station’s capacity in watt-hours doesn’t mean much until you know what it means in daily life. Below are concrete plans for a full day without power on three station sizes. To calculate for your own devices, use the calculator above or our power station calculator.
How to calculate
Runtime in hours ≈ capacity (Wh) × 0.85 ÷ load (W)
The 0.85 factor accounts for inverter losses. For devices powered from USB or 12 V, losses are smaller and you can use 0.9.
Example: a 12 W router on a 1,000 Wh station runs about 1,000 × 0.85 ÷ 12 ≈ 70 hours.
Idle draw
When you switch on the AC outlets, the station’s inverter uses 10–30 W by itself, even with nothing plugged in. Over 24 hours that’s 240–720 Wh, sometimes half the battery.
Rule: switch on AC only when you need it and use USB-C or 12 V for everything you can.
Plan 1: 500 Wh station (≈ 425 Wh usable)
Communications and light for a family, for a day.
| Device | Draw | Time | Energy |
|---|---|---|---|
| Wi-Fi router (via USB-C/12 V) | 10 W | 12 hours | 120 Wh |
| 4 phones, full charge | ~15 Wh each | once | 60 Wh |
| 2 LED lamps | 7 W each | 5 hours | 70 Wh |
| Laptop | 50 W | 2 hours | 100 Wh |
| Radio | 5 W | 5 hours | 25 Wh |
| Total | 375 Wh |
No fridge and no heating. For those you need a bigger station.
Plan 2: 1,000 Wh station, summer day (≈ 850 Wh usable)
| Device | Draw | Time | Energy |
|---|---|---|---|
| Fridge, plugged in with breaks | ~60 W average | 8 of 24 hours | 480 Wh |
| Router | 10 W | 24 hours | 240 Wh |
| Phones | once | 60 Wh | |
| LED lamps | 14 W | 5 hours | 70 Wh |
| Total | 850 Wh |
Plan 3: 1,000 Wh station, winter evening (≈ 850 Wh usable)
| Device | Draw | Time | Energy |
|---|---|---|---|
| Gas furnace blower or wall boiler (pump and controls) | ~120 W | 4 hours | 480 Wh |
| Router | 10 W | 12 hours | 120 Wh |
| LED lamps | 14 W | 5 hours | 70 Wh |
| Phones | once | 60 Wh | |
| LED TV | 60 W | 2 hours | 120 Wh |
| Total | 850 Wh |
Furnace blowers vary widely (some draw 300–800 W), so measure yours. The heating system must be able to run from an outlet and the station needs pure sine wave output. See our guide to backup power for a gas boiler.
Plan 4: 2,000 Wh station (≈ 1,700 Wh usable)
| Device | Draw | Time | Energy |
|---|---|---|---|
| Fridge, on continuously | ~50 W average | 24 hours | 1,200 Wh |
| Router | 10 W | 24 hours | 240 Wh |
| Phones and laptop | 160 Wh | ||
| LED lamps | 14 W | 5 hours | 70 Wh |
| Total | 1,670 Wh |
Or in winter: a boiler for 8 hours (≈ 960 Wh) plus router, lights, phones and TV.
How much a solar panel adds
| Panel | Clear summer day | Winter or cloudy day |
|---|---|---|
| 100 W | 300–500 Wh | 50–150 Wh |
| 200 W | 600–1,000 Wh | 100–300 Wh |
| 400 W | 1,200–2,000 Wh | 200–600 Wh |
Figures are indicative and depend on orientation, tilt, shade and latitude. In winter, don’t rely on a panel alone for long outages.
Tips for a long outage
- Charge everything to 100% when a storm, blizzard or heatwave is forecast.
- Prioritize: communications and light, then the fridge, then comfort.
- Batch your AC use: switch the outlets on once for the fridge and other devices, then off again.
- Keep the station warm in winter: batteries deliver less in the cold and won’t charge below freezing.
To choose a station, see how to compare power stations, and for the rest of your outage plan, our power outage guide.
Frequently asked questions
Why does my station run for less time than I calculated?
Three usual reasons: the inverter draws 10–30 W on its own while on, devices use more than their label says (especially fridges in summer), and batteries deliver less in the cold. Measure real use with a plug-in power meter and leave a 15–20% margin.
Should I power my router from USB or the AC outlet?
From the DC ports (USB-C or 12 V) if your router supports it, with the right cable. You avoid inverter losses and idle draw. The same goes for phones, laptops and lamps.
How long will a fridge run if it's on all the time?
A modern fridge-freezer averages about 40–80 W because the compressor cycles on and off. On a 1,000 Wh station that's 10–20 hours. You don't need to keep it on constantly: 1–2 hours every 4–6 hours with the door shut keeps it cold and doubles your runtime.
Can I run an air conditioner or space heater?
Only very briefly. A 1,500 W space heater drains a 1,000 Wh station in well under an hour. For heat, run your furnace blower or boiler controls (they use little power) or other sources; see our guide to heating without power.
Sources and further reading
Preper is for general education and does not replace instructions from your local authorities or advice from a doctor. In an emergency, call your local emergency number.