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 40-km Grid Data 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.
In this version, performance is first calculated for the the nearest TMY2 location and then translated to the desired 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 the 40-km Grid Data calculator.
For more information, see PVWatts Version 2 – Enhanced Spatial Resolution for Calculating Grid-Connected PV Performance.
To use the PVWatts Grid Data (Version 2) calculator, see:
- PVWatts Frequently Asked Questions
- PVWatts Version 2 Calculator
- How to Change PVWatts Parameters
- How to Interpret PVWatts Results
- PVWatts Revision History
About PVWatts™ Viewer
The PVWatts™ Viewer is an interactive map providing access to multiple data sets which link directly to their corresponding PVWatts Calculators, allowing the user to determine energy production and cost savings of grid-connected solar photovoltaic (PV) systems. Both calculators are accessible through the viewer by querying their corresponding data layers, which feature weather data in the form of specific locations (239 TMY2 sites in the United States and 76 international) as well as a 40km x 40km grid which covers the United States.
- Site Specific Data (Version 1) offer individual data for specific locations, depicted as a black cross with a yellow center.
- Grid Data (Version 2) allow users to create estimated performance data for any location in the United States and surrounding territories by selecting any point within one of the 40km grid cells.
The PVWatts Viewer provides easy access to both datasets. This application, built on ESRI Flex Viewer, utilizes an interactive web mapping interface that allows you to query both data sets simultaneously for any specified location. The screenshot below illustrates the various data sets as they are displayed in the PVWatts Viewer. Station locations are indicated by a black cross with a yellow center and a 40km solar resource grid (yellow to red squares) is overlaid on top of a street map of the United States.