A complete useful tool for Solar PV system sizing, Rooftop and Electrical calculations. SOLAR PV CALCULATIONS • Solar PV calculations, • PV array shadow calculations, • Simple SPV off-grid load calculations, • SPV off-grid system sizing calculations, • PV water pumping calculations, • Solar voltage drop calculations, • Solar rooftop calculations, • Solar irradiance with monthly data, • Tilt angle with monthly data. ELECTRICAL CALCULATIONS • Ohm's Law, • Voltage drop calculations, • Cable cross