Tick the appliances you actually want to run, and watch your daily energy use, peak load and a ballpark solar-plus-battery size update live — before you talk to anyone.
Defaults assume a typical off-grid US home — ~4.5 peak sun hours, $ pricing, 240V dryer/range further down.
Defaults assume a typical off-grid European home — ~3.2 peak sun hours (PVGIS-style), € pricing, 230V kettle further down.
PSH
Wh/day
150W is compressor running wattage, not a 24h draw — compressor duty cycle ≈ 8h/day equivalent, which is what the hours field defaults to.
Wh/day
Wh/day
Wh/day
Pump motors surge hard on start-up — roughly 3× running watts for a second or two. That spike is folded into the surge estimate below, not into daily kWh.
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Wh/day
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240V split-phase appliances need a split-phase/NEMA-aware inverter or transfer setup — not every off-grid inverter supports this natively.
Wh/day
230V single-phase is standard European off-grid wiring — no split-phase inverter needed.
Can you run this off-grid?
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Daily energy use
0 kWh/day
Peak running load
0 W
Estimated surge
0 W
Ballpark solar array
0 kW
Ballpark battery bank
0 kWh usable
How this is calculated
Every appliance you tick contributes watts × hours run per day to the total — the energy math a battery bank actually has to hold. Untick anything you wouldn't run off-grid; the defaults above are typical values, not your house.
Peak running load is the sum of running watts for everything ticked — the continuous rating your inverter needs to clear if it all ran at once. Estimated surge adds the start-up spike of your single biggest motor on top (compressors and pumps commonly pull 2–3× running watts for a second or two) — not every motor's surge added together, since motors essentially never start in unison. Same rule generator and inverter sizing guides use.
The ballpark array divides daily kWh by your peak sun hours and a roughly 78% system-efficiency figure, which folds in inverter, charge-controller, wiring and battery round-trip losses. The ballpark battery bank multiplies daily kWh by two days of stored autonomy and divides by an 80% usable depth-of-discharge — a common sizing rule for LiFePO4 off-grid banks.
Fridges, freezers, well pumps and mini-splits cycle on and off — the hours/day defaults already approximate typical duty cycles, not continuous run time.
Peak sun hours is the single biggest lever on array size — swap in your own location's number (PVGIS for Europe, NREL for the US) for a tighter estimate.
These are planning-stage numbers, not a system design. An installer sizes the real thing from a load study and a look at your roof or site.
If your verdict says a big battery can carry the house, this is the hardware tier it means. Picked on merit from what’s on the market right now — street prices, checked July 2026.
Anker SOLIX F3800 — 6,000W with genuine 120/240V split-phase from a single unit — carries a well pump or dryer where rivals need a second box. $1,999–2,400 · View
EcoFlow DELTA Pro 3 — 4kWh base, 4,000W output, expandable to 12kWh — the storage-first pick when your verdict says “close, but batteries”. $2,700–3,000 · View
Some links above may earn Grid CEO a referral fee at no cost to you — disclosure.
EcoFlow DELTA Pro 3 — 4kWh, 3,600W continuous at 230V, expandable to 12kWh. €2,800–3,500 · View
EcoFlow DELTA 3 Plus — 1kWh expandable to 5kWh — the smaller wall when your load list comes back modest. €700–850 · View
Some links above may earn Grid CEO a referral fee at no cost to you — disclosure.
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