Solar PV Calc is a FREE professional solar power system designer and calculator.
Used by homeowners, solar installers, and engineers to size complete off-grid and backup solar systems using real engineering formulas.
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ⚡ WHAT YOU CAN CALCULATE ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ✓ Solar panel array size (Wp) from daily energy needs ✓ MPPT charge controller amperage (sized by array, not load) ✓ Pure sine wave inverter sizing with 25% safety margin ✓ Battery bank capacity (Ah) at 50% depth of discharge ✓ DC & AC circuit breaker ratings ✓ PV string fuses and surge protection devices (SPD) ✓ Complete safety equipment list
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🔧 KEY FEATURES ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ✓ Add household appliances with wattage, voltage & daily hours ✓ 12V / 24V / 48V DC system support ✓ Automatic current calculation (I = W/V) ✓ Professional wiring diagrams ✓ Complete materials shopping list with quantities ✓ Step-by-step installation guide ✓ Financial ROI calculator — payback period & 25-year savings ✓ Cable sizing & panel angle calculator (Advanced Tools) ✓ Calculation history — save and compare multiple system designs ✓ Environmental impact — CO₂ saved and trees equivalent ✓ 100% offline — works without internet connection ✓ All data saved locally — no account required
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 📐 REAL ENGINEERING FORMULAS ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ • Daily Energy (kWh) = Σ(Watts × Hours) / 1000 • Solar Array (Wp) = Daily kWh / (Peak Sun Hours × 0.75) • Inverter (W) = Total Load × 1.25 • MPPT Controller (A) = Array Wp / Battery V × 1.25 • Battery Bank (Ah) = Daily Wh / (System V × 0.50)
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🌏 DESIGNED FOR THE PHILIPPINES ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ • 5 peak sun hours (Philippine average) • 230V AC, 50Hz standard output • 550Wp monocrystalline panel sizing • MPPT models available in the Philippine market
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ⭐ PRO VERSION (OPTIONAL) ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Go PRO with a single one-time purchase to enjoy a completely ad-free experience. All features remain free — PRO only removes ads.
Built by DarskeeWorks — solar engineering meets mobile technology.
Note: This app provides educational estimates for planning purposes. Always consult a certified solar installer before any actual installation.