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Power station calculator: what size do you need?

Add each device once and set its hours a day. The calculator checks running watts, starting watts and hours on 43 current stations calculated, from maker specs maker spec with list prices checked . Your plan is saved in the page address, so you can bookmark or share it. Nothing is sent to a server.

1. Your devices

No devices yet. Add a fridge, CPAP, router, or anything else you want to keep running.

2. Your plan

Example: a fridge through a 24-hour outage

A worked plan with live picks, so you can see what the shortlist gives for a common case before entering your own devices.

Yes. PECRON E2400LFP runs a full-size fridge through a 24-hour outage for about 33 h. calculated from maker specs, .

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Best fit
PECRON E2400LFP
About 33 h calculated
2,048 Wh LiFePO4 · 2,400 W continuous
Starting headroom 75%
$649 list price, checked · In stock
3-year warranty · 20.5 kg
Cheapest in-stock station with at least 20% spare runtime, a published warranty of at least two years and a published surge rating.
Check price for PECRON E2400LFP
Budget
PECRON E1500LFP
About 25 h calculated
1,536 Wh LiFePO4 · 2,200 W continuous
Starting headroom 77%
$549 list price, checked · In stock
5-year warranty · 17.4 kg
Cheapest in-stock station that works at all; trade-off: less than 20% spare runtime.
Check price for PECRON E1500LFP
More headroom
PECRON F3000LFP
About 50 h calculated
3,072 Wh LiFePO4 · 3,600 W continuous
Starting headroom 78%
$899 list price, checked · In stock
5-year warranty · 28.7 kg
Cheapest station that works in the next size class up (3,000–4,999 Wh).
Check price for PECRON F3000LFP

Goal: 24 h. Hours use maker inverter efficiency where published, otherwise the 0.85 estimate, and leave out idle draw the maker doesn't publish. Stations shown out of stock or with availability not shown are skipped. How we pick.

How the estimate works

  • Runs: your devices' running watts added together must fit the station's continuous rating.
  • Starts: the others running plus the largest motor or compressor start must fit the surge rating. With no published surge rating we compare to continuous and say so.
  • Hours: rated Wh × (1 − reserve), divided by (your average watts plus idle draw) ÷ inverter efficiency.
  • Boost modes are never counted. Outside the maker's temperature range we show "not supported by maker" and no hours.

Device watts come from cited sources (ENERGY STAR data, maker manuals, and a generator maker's wattage chart); your own label reading always wins. Read the methodology and the data sources.