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.

Energy Needs

Enter your daily energy consumption. Use the Home Load Calculator to find your exact daily usage.

Daily Energy Consumption (Wh/day)

4.62 kWh/day

Peak Simultaneous Load (W)

Inverter must handle at least 1,250 W

Location & Sunlight

Peak sun hours determine how much power your panels can generate each day.

Your Region

e.g. Illinois, Ohio, Kansas

4.5 hours/day

Average peak sun hours for Midwest US

System Configuration

Configure your system preferences to get accurate sizing recommendations.

Battery Type

System Voltage

Panel Wattage

Days of Autonomy

2 days

1 day7 days

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

1,600

Panels

× 400W

Battery

578

Ah @ 24V

Inverter

1,500

Solar Array

4 panels

400W × 4 = 1,600 W total

Min required: 1,369 W (at 4.5 peak sun hrs)

Shop 400W solar panels

Battery Bank

13,860 Wh

578 Ah at 24V · LiFePO4

2 days autonomy · 20% safety margin

Shop 24V LiFePO4 batteries

Inverter & Charge Controller

Inverter

1,500 W

pure sine wave

MPPT Controller

100 A

charge controller

Shop 1,500W inverters Shop 100A charge controllers

Estimated Cost

Solar panels$1,280

Battery bank$4,158

Inverter$375

Charge controller$480

Wiring & mounting$944

Total Estimate$7,237

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.

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