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3 kWh

The load sheet that stops you buying the wrong array.

Daily watt-hours decide everything. Panels, battery, inverter — they're just math on top of what you actually run.

People shop panels first. That's backwards. A microwave for 15 minutes is 250 Wh. An induction burner for 45 minutes is 1,125 Wh. Heat is what blows solar budgets. Propane or wood wins there in 2026 economics.

Use it in 10 minutes. List every load × hours. Sum Wh/day. Array watts ≈ daily Wh ÷ sun hours ÷ 0.75. Bank Wh ≈ daily Wh × days of autonomy ÷ DoD (0.80 LiFePO4, 0.50 AGM).

Typical daily loads

LoadWattsHrs/dayWh/day
Energy Star refrigerator1508 (cycled)1,200
LED lights, cabin (10 bulbs)805400
Laptop + phone charging1006600
12 V water pump600.530
CPAP machine408320
Starlink / internet6012720
TV1004400
Microwave1,0000.25250
Induction cooktop (per burner)1,5000.751,125

Draw figures are published manufacturer/DOE typicals on solar-sizer.com.

Worst-month sun hours

ClimatePeak sun hrs/day
US Southwest (AZ, NV, NM)5–6
US Sun Belt average4–5
Pacific Northwest winter1.5–2.5
Northeast / Midwest winter2–3

A minimalist cabin at 3 kWh/day typically wants about 1,200–1,500 W of panels in most of the US, with a 400–600 Ah 12 V LiFePO4 bank (or 24/48 V equivalent) to ride cloudy days.

Comment keyword: SUN — that's the word we ask for on X/LinkedIn. We DM this page.

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