Free off-grid calculators

Free solar, battery, load, rainwater and preparedness calculators.

• Solar Array & Battery Sizer — Size your panel count, MPPT controller amperage, and LiFePO4 battery bank in kWh with cold-temperature safety buffers.
• Homestead Load Consumption Profiler — Catalog daily appliance wattages, detect deep well pump surge spikes, and export direct into the Solar Calculator.
• Rainwater Catchment Tool — Compute annual gallons harvested from your roof sq ft and dimension freeze-protected underground cistern capacity.
• 5-Pillar SHTF Readiness Audit — Audit your off-grid vulnerabilities across power, water, calorie seeds, tactical comms, and field medical gear.
• DC Wire Gauge & Voltage Drop Calculator — Calculate exact DC voltage drop across copper cable runs between your solar array, charge controller, battery bank, and inverter.
• Generator Fuel & Run-Time Estimator — Determine fuel gallons required for continuous emergency generator run time based on homestead electrical load.