Solar System Calculator
Size your solar panel array, battery bank, and inverter based on your energy needs and location.
New to off-grid? Start with our 3-question path finder for a personalized off-grid guide.
Calculation Assumptions
- 75% overall system efficiency (wiring, temperature derating, charge controller, battery round-trip)
- LiFePO4: 80% depth of discharge · Lead-acid: 50% depth of discharge
- 20% battery safety margin for capacity headroom
- Prices in USD as of 2026-06-19. USD base prices, typical US retail market. Verify quarterly on manufacturer sites, Amazon.com, or Home Depot.
- Inverter sized at 1.25× peak load; MPPT controller sized at 1.25× array watts ÷ system voltage
System Summary
Updates live as you adjust inputs.
Solar Array
800
W
Panels
2
× 400W
Battery
250
Ah @ 24V
Inverter
1,500
W
Solar Array
2 panels
400W × 2 = 800 W total
Min required: 593 W (at 4.5 peak sun hrs)
Shop 400W solar panelsBattery Bank
6,000 Wh
250 Ah at 24V · LiFePO4
2 days autonomy · 20% safety margin
Shop 24V LiFePO4 batteriesInverter & Charge Controller
Inverter
1,500 W
pure sine wave
MPPT Controller
60 A
charge controller
Estimated Cost
Federal ITC (expired 2025) does not apply to systems installed in 2026 — the total above is your full estimated cost.
Estimates based on USD base prices, typical US retail market. Verify quarterly on manufacturer sites, Amazon.com, or Home Depot. Prices as of 2026-06-19. Does not include installation labor or permitting.