Solar Power for a Rural Cabin or Off-Grid Shed: What Size Do You Really Need?

Short answer: A rural cabin with a fridge, lights, TV, and basic tools needs 2,000–4,000 Wh daily. Without solar recharge, you need 4,000–8,000 Wh stored capacity for a 2-day buffer. With a 400W solar panel in good conditions, a 2,000–3,000 Wh system runs indefinitely for basic loads. A well pump changes the equation significantly.

Cabin Loads vs Camping Loads

A rural cabin or off-grid shed is fundamentally different from camping. The loads are higher, the runtime expectations are longer, and reliability matters more. You’re not trying to survive one night — you’re trying to run a functional space indefinitely.

Typical Cabin Daily Loads

Load	Watts	Hours/day	Duty cycle	Daily Wh
Refrigerator	120W	24h	40%	1,152 Wh
LED lights ×6	60W	5h	100%	300 Wh
TV / screen	80W	3h	100%	240 Wh
Laptop	65W	4h	100%	260 Wh
Router	15W	12h	100%	180 Wh
Phone charging ×2	20W	2h	100%	40 Wh
Total (no pump)				2,172 Wh/day

The Well Pump Factor

If your cabin has a well pump, it adds 500–2,000 Wh/day depending on usage and pump size. More importantly, the startup surge requirement (2,000–5,000W for a ½–1 HP pump) determines which power station you can use. A unit with less than 3,000W surge cannot reliably start most well pumps.

Sizing with Solar Recharge

The key advantage of pairing a solar generator with panels: you don’t need to store multiple days of energy — you recharge daily. With 400W of solar panels and 5 peak sun hours, you generate ~2,000 Wh/day — enough to run the cabin indefinitely in good weather.

For cloudy days, size your battery to cover 2–3 days without sun. At 2,172 Wh/day, that means 4,344–6,516 Wh of storage. The EcoFlow Delta Pro (3,600 Wh) covers 1.5 cloudy days; the Bluetti AC300+2×B300 (6,144 Wh) covers nearly 3 days.

Recommended Systems by Cabin Size

Cabin type	Daily Wh	Recommended storage	Recommended solar	Best unit
Small shed / workshop	500–800 Wh	1,000–1,500 Wh	200W panel	EcoFlow Delta 2
Basic cabin (no pump)	1,500–2,500 Wh	2,500–4,000 Wh	400W panels	EcoFlow Delta Pro
Cabin with well pump	2,500–4,000 Wh	4,000–7,000 Wh	600W+ panels	Bluetti AC300+2×B300

Related Guides

• Can the EcoFlow Delta Pro run a well pump?
• Solar generator sizing guide
• EcoFlow Delta Pro vs Bluetti AC300

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