The SAM web site will be upgrading Monday, May 23 from 4:00-5:00pm (Denver/mountain time). 

After doing a major change to our infrastructure, we have found a minor issue that we have corrected but will need to reboot the web site for it to take affect.

To make it as convenient as possible, we have scheduled it for Monday, May 23rd at 4:00pm (mountain). The process takes 15-20 minutes, but the site will only be unavailable for a short time. However, your session information will be lost (eg if you're writing a post, what you have written could be lost). 

Downloading Solar Resource Data, Sep 2018

Supporting materials

Managing the Solar Resource Library in SAM

P50/P90 Analysis

About the National Solar Radiation Database (NSRDB)