calc.engineer / Solar & Power / Solar Sizing

Solar Sizing v1.0.0

Sizes an off-grid solar power system by calculating the number of panels and battery bank capacity required for a given daily energy consumption. Accounts for system losses (inverter, wiring, charge controller), battery depth-of-discharge, and autonomy days for cloudy weather. Outputs panel count, total panel wattage, battery capacity in kWh and Ah, and minimum charge controller amperage (with 25% safety margin per NEC 690.8). Supports 12V, 24V, and 48V system architectures. Use for cabin, RV, telecom tower, and remote IoT deployments.

← from battery_lifefeeds wire_gauge →feeds battery_life →feeds ups_runtime →
Daily energy consumption in kilowatt-hours (kWh)
Average peak sun hours per day for your location (hours)
Rated wattage per solar panel (W)
Battery bank system voltage: 12, 24, or 48 V
Number of days the battery bank should sustain load without solar input
Battery depth of discharge (0-1), default 0.8 for LiFePO4
Overall system efficiency (0-1), accounts for inverter, wiring, and controller losses
Fill in the inputs and Compute to see the structured result.

From an agent (MCP) or the API

curl -X POST https://calc.engineer/api/solar_sizing \
  -H "Content-Type: application/json" \
  -d '{"daily_kwh": …, "peak_sun_hours": …, "panel_watts": …}'

MCP: connect to https://calc.engineer/mcp and call solar_sizing.

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