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Calculated scenario · sourced manifest

Portable Power for a Three-Day Outage

1 station passes every configured check; 78 fail at least one.

Energy per day
2,952 Wh
Sourced manifest ↓
Running load
334 W
Sourced manifest ↓
Worst-start surge
1,354 W
Sourced manifest ↓
Required delivered energy
8,856 Wh
Sourced manifest ↓
Stations passing
1
Sourced manifest ↓
Stations failing
78
Sourced manifest ↓
Edit this plan in the sizing tool →

By the BatteryRank Engineering Team

01 · Load manifest

Every load in the calculation

Average draw applies each sourced duty cycle; energy is average draw × quantity × daily hours × scenario days.

Sourced device loads and calculated energy
DeviceQuantityHours / dayAverage drawScenario energySource
Refrigerator (full-size)AC12463 W4,536 WhSource · 2026-07-06
Chest freezerAC12430 W2,160 WhSource · 2026-07-06
Wi-Fi router + modemAC12418 W1,296 WhSource · 2026-07-06
LED lamp (60W-equivalent bulb)AC489 W864 WhSource · 2026-07-06

02 · Reading the plan

What the numbers for a three-day outage leave out

What this situation actually demands

Three days is the point where a battery stops being the answer. The manifest asks for 8,856 Wh delivered, and the two cold appliances are 2,232 Wh of every 2,952 Wh day — 76% of the plan sits in two compressors. Only the largest, heaviest tier of the catalogue carries that on stored energy alone, which is why the useful question here is not "how big a battery" but "how does it get refilled". The 400 W array in this plan is not an accessory to the answer; over 72 hours it is most of it.

Where these plans go wrong

Treating 72 hours as a capacity figure. Multiply the day out, arrive at 8.9 kWh, and you have specified a station that weighs more than most people can move alone and costs more than the food it protects. The second mistake is subtler: the always-on Wi-Fi router draws 18 W around the clock, which is 432 Wh a day — half again what four LED lamps burn in eight hours, and 1,296 Wh across the outage. Nobody budgets for the router, and it is the third-largest line on this plan.

What this plan does not model

The 0.35 and 0.30 duty cycles behind those compressor figures describe appliances holding temperature in a conditioned house. Three days into a summer outage the house is not conditioned, and both cabinets will cycle harder than modelled. The solar side is looser still: the harvest shown assumes usable sun, and a multi-day grid failure is usually caused by the weather that removes it. Neither figure knows your latitude, your season, or the storm that started this.

03 · Station picks

The one station that covers this plan

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Solar-balanced plan

EcoFlow DELTA Pro Ultra X

Projected runtime
3.5 days
Headroom
17.9%
Weight
135.5 kg

Why it fits

10,000 W sourced solar-input ceiling; 10,000 W usable in this plan

Main compromise

No measured compromise across 1 eligible models

Open sourced model dossier →

Solar balance

What recharging changes

On EcoFlow DELTA Pro Ultra X, the configured 400 W array harvests 1,120 Wh/day.

The remaining deficit is 2,353 Wh/day, for about 5.2 days of modeled runtime.

Review the published solar method →

Explore passing models by projected runtime

This ordered data view is separate from the single recommended buying strategy above.

  1. 01EcoFlow DELTA Pro Ultra X3.5 days

Questions from the same calculation

How much power do you need for a three-day outage?
8,856 Wh of delivered energy over 3 days, drawing 334 W if every device runs at once. Refrigerator (full-size) alone is 51% of that energy, so it is the load worth measuring first — the rest of the manifest barely moves the answer.
What decides whether a station can start this setup?
Refrigerator (full-size). Its sourced 1,200 W startup demand, arriving while the other devices keep running, sets a worst-case moment of 1,354 W — well above the 334 W running total. A station sized only to the running figure will carry this plan right up until that device restarts.
Why is every load on this plan running through the inverter?
None of the devices in this manifest has a manufacturer-supported DC input, so each one pays the DC-to-AC conversion cost. Where a device does offer a native 12 V cord — camping fridges especially — using it is the cheapest runtime you can buy.
Do I really need three days of stored energy?
Almost certainly not, and planning that way is what makes this scenario unaffordable. The 8,856 Wh figure assumes both compressors and the router run untouched for the full 72 hours. In practice people run cold appliances in blocks and watch a thermometer instead of a clock, which is a rationing decision rather than a purchase decision — and it moves the requirement far more than any station in the catalogue does.
Why does adding solar change this more than adding capacity?
Because capacity is spent once and an array is spent daily. A station that covers one day of this manifest and recharges each morning covers three days; a station holding three days of energy with no way to refill covers exactly three days and then stops. At the 2,952 Wh daily figure, an array that closes even half the gap turns a fixed deadline into an open-ended one.
What can I cut from this plan, and what has to stay?
The four LED lamps are 288 Wh a day between them — under 10% of the plan, and the cheapest comfort you can keep. The router is 432 Wh, and unlike the lamps it buys nothing while you sleep, so a timer on it is the single easiest saving here. The refrigerator and the freezer are the plan; everything else is noise around them.