When evaluating a 325kW photovoltaic panel, the output current depends on three critical factors: system voltage, power factor, and environmental conditions. Using Ohm's Law (Current = Power / Voltage), a 325kW system operating at 480V AC would theoretically generate approximately. Estimate daily, monthly, and yearly solar energy output (kWh) based on panel wattage, quantity, sunlight hours, and efficiency factors. Losses come from inverter efficiency, wiring, temperature, and dirt. Increasing panel count or choosing higher wattage. Technical parameter Maximum Power (W) 80W Optimum Power Voltage (Vmp) 15. 90V Optimum Operating Current (Imp) 5. solar installer uses is kWh/day = kW × PSH × derate, where the derate factor is 0. 83 by NREL PVWatts v8 default — or 0.