What is PVWatts?

PVWatts is a web application developed by the National Renewable Energy Laboratory (NREL) that estimates the electricity production of grid-connected photovoltaic (PV) systems throughout the world. Users input information about their PV system (size, location, tilt, array type, module type, inverter efficiency, etc.), and PVWatts provides estimates of monthly and annual energy production, as well as other performance metrics. It is commonly used for preliminary feasibility studies, system design optimization, and educational purposes.