The answer — one pick, priced
Get the
Anker SOLIX F3800
no budget ceiling
Real 120V/240V backup at a tenth the cost of an installed system — 6,000 W, transfer-switch ready, and expandable to 26.9 kWh as your loads grow.
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Fit ledger — need → measured evidence
■ The catch — co-equal billing, always
3.84 kWh is critical-circuit capacity, not a whole house. It is a fraction of the 30 kWh+ the field converged on for true whole-home coverage, and feeding panel circuits still means paying an electrician for a transfer switch. Getting to 26.9 kWh means buying expansion batteries at full price.
Dealbreaker? Runner-up №2 lifts the ceiling to 90 kWh ↓
■ Every product has a catch. Verdicts that hide it are how bad buys happen.
Runners-up — if your needs differ
Adjacent verdicts — same method
Traps — this verdict avoids
The vanished 30% credit
The One Big Beautiful Bill Act killed the 30% federal 25D credit for homeowner-owned batteries finished after 2025-12-31 — and the IRS counts the expenditure when installation is *completed*, so a 2026 install gets nothing. That is $3,500–$5,500 of real cost added back to an installed system. Not tax advice.
Surge watts aren't run watts
Continuous (rated) wattage powers your loads; peak/surge figures last 3–10 seconds and only cover motor-start inrush. A single 13.5–15 kWh battery rarely runs central AC and an electric range at the same time without load management.
Whole-home math
True whole-home coverage needs 30 kWh+ of usable storage — most homes start with one 10–15 kWh unit on critical circuits (fridge, lights, internet, well pump). And installed quotes of $11,500–$18,500 per battery include labor and permits, while Amazon prices are hardware-only.
Provenance — 11 sources, dated
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