Keeping the lights on...NOAA helps improve solar energy forecasts for more efficient power management

solar instruments
Total sky imager for tracking clouds at a Solar Facility in Southern Colorado (Credit: David Longenecker, CIRES)

Providing people with the electricity necessary for day-to-day life is the priority of power companies. The U.S Department of Energy (DOE) SunShot initiative launched in June 2011 is a collaborative effort with the goal to make solar energy cost-competitive with other forms of electricity by the end of the decade. Solar increases the diversity of the nation’s electrical sources, promotes energy independence and national security while reducing environmental concerns. Because the power produced by sunlight-converting photovoltaic (PV) plants can be quickly reduced by passing clouds, there is an inherent degree of high variability that provides challenges for power grid operators. As part of the SunShot Initiative, researchers from NOAA’s Earth System Research Laboratory (ESRL) are working with collaborators on a DOE-sponsored project to develop better short-term (hours to day-ahead) solar energy forecasts that will help improve the operation of the electric power grid and lower integration costs for solar power. These improvements will help power providers to better manage their grid system needed to dependably ‘keep the lights on’ while reducing spinning reserves.

“NOAA is uniquely qualified to provide forecasts on weather dependent energy resources such as wind and solar,” says Kathy Lantz, a CIRES researcher working at ESRL’s Global Monitoring Division (GMD). “This is an exciting area of research with many societal benefits.”

GMD will provide high-quality solar irradiance (solar radiation) data from their seven fixed SURFRAD stations, and seven fixed ISIS stations across the U.S. These stations collect global horizontal solar irradiance measurements and their components direct beam solar irradiance as seen by concentrating solar power systems and scattered solar irradiance. These sites also collect measurements of phenomena that attenuate solar irradiance in the atmosphere, such as aerosols and clouds.

“Our long-term NOAA SURFRAD and ISIS stations, including two recent power plant locations, will provide accurate solar irradiance data to verify improvements in the solar irradiance forecast,” says Lantz.

GMD has also built two moveable SURFRAD systems. One system will spend a year co-located at a Xcel Energy PV plant in the San Luis Valley of Colorado, in collaboration with NCAR. A second moveable SURFRAD system will be deployed in October in Rutland, Vermont, at a Green Mountain Power PV station in collaboration with IBM.

ESRL’s Global Systems Division (GSD) has a significant involvement in the project. They are focused on improving solar forecasts for the six-hour and day ahead periods in their state-of-the-art weather models.

“NOAA is always working to improve its weather forecasts,” says Melinda Marquis, team leader of ESRL’s Renewable Energy Program. “As a result of this project, GSD is working to improve forecasts of irradiance from NOAA Rapid Refresh weather models, which provide foundational forecasts to many sectors. Comparing output from the models to observations collected at the SURFRAD and ISIS stations is a key step in this effort. We look forward to more feedback from our partners at NCAR, IBM, and the power industry.”

CIRES is a partnership of NOAA and CU-Boulder


  • Kathy Lantz, CIRES researcher at NOAA's Earth System Research Laboratory, 303-497-7280
  • Barb DeLuisi, a Communication Specialist at NOAA's Earth System Research Laboratory, 303-497-4233