Scenarios › What size power station for an off-grid cabin

What size power station / solar generator for an off-grid cabin?

A weekend cabin runs a fridge, lights, WiFi, and electronics off solar, topped up each day. You size for the overnight-and-buffer window the battery carries alone, then match solar input to replace it by day. Here is a 12-hour buffer for a modest cabin, and the expandable units worth it if you want to coast through cloudy stretches.

3,107 Whcapacity needed

330 Wrunning watts

1,380 Wsurge to clear

12 hruntime horizon

This load: Refrigerator (modern) · LED Lights (10 bulbs) · WiFi Router + Modem · Laptop. Want to tweak it? Open the full sizing tool and adjust the appliances and hours.

What size you need

You need about 3,107 Wh — and 4 units fit. The smallest sufficient is the EcoFlow DELTA Pro; we never push more capacity than your load can use. Surge to clear: 1,380 W.

The math
Running watts (everything on at once) = 330 W
Surge watts (worst single startup + the rest running) = 1,380 W
Average draw (cyclic loads counted by their duty cycle) = 233 W
Watt-hours = 233 W × 12 h ÷ 90% usable reserve = 3,107 Wh

EcoFlow DELTA Prosmallest that fits

3,600 Wh 3,600 W cont · 7,200 W surge expandable ~14 h on this load $$$

The whole-home contender on wheels — 3,600 W, expandable to 25 kWh, panel-ready with a transfer switch.

LiFePO4 · AC + EV charging; expandable to 25 kWh · 99 lb

Check price at EcoFlow → Full specs

Anker SOLIX F3800

3,840 Wh 6,000 W cont · 9,000 W surge expandable ~15 h on this load $$$

A 6,000 W, 240 V system for whole-home backup including a well pump and electric range, expandable to ~27 kWh.

LiFePO4 · 120/240 V; expandable to 26.9 kWh · 132 lb

Check price at Anker SOLIX → Full specs

Goal Zero Yeti PRO 4000

3,993 Wh 3,600 W cont · 7,200 W surge expandable ~15 h on this load $$$

Goal Zero’s LiFePO4 flagship — 4 kWh, 3,600 W, whole-home with the transfer switch and tanks.

LiFePO4 · Fast AC; expandable to ~27 kWh · 104 lb

Check price at Goal Zero → Full specs

EcoFlow DELTA Pro 3

4,096 Wh 4,000 W cont · 8,000 W surge expandable ~16 h on this load $$$

A 4 kWh, 4,000 W (120/240 V) system built specifically for whole-home backup.

LiFePO4 · AC/solar/EV; expandable to 48 kWh · 113 lb

Check price at EcoFlow → Full specs

🔗 The "Check price" buttons are brand-direct affiliate links. Once our brand affiliate programs are approved these will earn a commission — at no extra cost to you, and it never changes which unit we recommend. Disclosure.

The load, appliance by appliance

Appliance	Running	Surge	Duty
Refrigerator (modern)	150 W	1,200 W	35%	size on its own →
LED Lights (10 bulbs)	100 W	—	100%
WiFi Router + Modem	20 W	—	100%
Laptop	60 W	—	100%

⚡ Informational only — a computed sizing estimate from published appliance-wattage charts and manufacturer station specs. It is not an electrical guarantee. For hardwired or whole-home backup, transfer switches, or any permanent install, consult a licensed electrician. Appliance wattages are representative chart values and vary by model; check your nameplates. Duty cycle (how much of the time a load actually draws) is how we keep the watt-hour estimate from overselling capacity.

Common questions

What size power station / solar generator for an off-grid cabin?

For Refrigerator (modern), LED Lights (10 bulbs), WiFi Router + Modem, Laptop over 12 h, you need about 3,107 Wh of capacity, 330 W continuous output, and at least 1,380 W of surge. The smallest unit that clears all three is the EcoFlow DELTA Pro; a step-up like the next size adds headroom for longer outages.

How many watt-hours does this load need?

About 3,107 Wh for 12 h — we take the duty-weighted average draw (233 W, since cyclic loads like fridges and pumps don't run constantly), multiply by the hours, and divide by a usable-capacity reserve. Running watts are 330 W; surge is 1,380 W.

Other scenarios

Power station for a home outage (fridge + CPAP + sump pump)

12 h

What size power station runs a CPAP all night?

8.0 h

What size power station / battery backup for a sump pump?

6.0 h

What size power station / solar generator for van life?

12 h

What size power station runs a refrigerator in an outage?

24 h

What size power station runs a 1500 W space heater?

3.0 h

Sources: appliance wattages — standard appliance/generator sizing charts; station specs — manufacturer published specifications (compiled 2026-06-15; approximate). Informational only — a computed sizing estimate from published appliance-wattage charts and manufacturer station specs. It is not an electrical guarantee. For hardwired or whole-home backup, transfer switches, or any permanent install, consult a licensed electrician.