National Solar Radiation Data Base

1991- 2005 Update: Typical Meteorological Year 3
Brief Summary of the TMY3s

This directory contains the data files for the typical meteorological year (TMY) data sets derived from the 1961-1990 and 1991-2005 National Solar Radiation Data Base (NSRDB) archives. Because they are based on more recent and accurate data, these new TMY3 data sets are recommended for use in place of earlier TMY2 data. The TMY3 data set contains data for 1020 locations, compared with 239 for the TMY2 data set.

The TMY3s are data sets of hourly values of solar radiation and meteorological elements for a 1-year period. Their intended use is for computer simulations of solar energy conversion systems and building systems to facilitate performance comparisons of different system types, configurations, and locations in the United States and its territories. Because they represent typical rather than extreme conditions, they are not suited for designing systems to meet the worst-case conditions occurring at a location.

TMY, TMY2 and TMY3 data sets cannot be used interchangeably because of differences in time (solar versus local), formats, elements, and units. Unless they are revised, computer programs designed for TMY and TMY2 data will not work with TMY3 data. NREL provides a conversion program to reformat TMY3 data to TMY2 data (see the Software section below.)

The TMY3 data sets and manual were produced by NREL's Electric Systems Center under the Solar Resource Characterization Project, which is funded and monitored by the U.S. Department of Energy's Energy Efficiency and Renewable Energy Office.

20-AUG-2008 NOTICE

All illuminance values for all TMY3 stations from January 2 to 31 should be multiplied by 100 to obtain the correct units of Lux. All luminance values for the same dates should be multiplied by 10 for the correct units of Candela per square meter.

NREL will be posting a corrected data set in the near future.

The Data



Map of TMY3 Sites

Figure 1. Shows the geographical coverage of the TMY3 ground stations.

Related Data Sets

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