Resource

PV WATTs Version 2

Estimates performance data for any location in the United States

Version 2 of the PVWattsTM calculator allows users to select a photovoltaic (PV) system location in the United States from an interactive map. The PVWatts Version 2 calculator uses hourly typical meteorological year weather data and a PV performance model to estimate annual energy production and cost savings for a crystalline silicon PV system. It allows users to create estimated performance data for any location in the United States or its territories by selecting a site on a 40-km gridded map. The PVWatts Version 2 calculator considers data from a climatologically similar typical meteorological year data station and site-specific solar resource and maximum temperature information to provide PV performance estimation.

For Version 2, performance is first calculated for the the nearest TMY2 location and then translated to the desired Version 2 40-km grid cell location. The translation process uses grid cell monthly values of solar radiation and meteorological parameters. Because the translation process uses monthly values, hourly values of PV performance are not available for Version 2.