PVWatts Calculator

Estimates the energy production and cost of energy of grid-connected photovoltaic (PV) energy systems throughout the world.NREL's PVWatts Calculator is a web application developed by the National Renewable Energy Laboratory (NREL) that estimates the electricity production of a grid-connected roof- or ground-mounted photovoltaic system based on a few simple inputs. It allows homeowners, small building owners, installers and manufacturers to easily develop estimates of the performance of potential PV installations. To use the calculator, you type the address or geographic coordinates of the system's location, specify the system size and array orientation, and provide some information about the system's cost and electricity rates. PVWatts calculates estimated values for the system's annual and monthly electricity production, and for the monetary value of the electricity.The PVWatts Calculator is suitable for very preliminary studies of a potential location for a photovoltaic system that uses crystalline silicon photovoltaic modules.