Project Name: Development of WRF-Solar v2—Improving Solar Forecasts
Funding Opportunity: Solar Forecasting 2
SETO Subprogram: Systems Integration
Location: Richland, WA
SETO Award Amount: $1,214,515
Awardee Cost Share:  $136,080
Principal Investigator: Larry Berg

This project will develop the second version of the Weather Research and Forecasting-Solar (WRF-Solar) model with special modifications that improve forecasts of solar irradiance. With these improvements, WRF-Solar v2 will be a new tool that improves intra-day and day-ahead forecasts. This version of WRF-Solar will function as an open-source model for solar forecasting researchers and could become the new standard for irradiance forecasting.

APPROACH

The research team will develop enhancements to WRF-Solar that address known shortcomings in the first version. Enhancements will include improved treatments of clouds and particles in the atmosphere that scatter or absorb sunlight, and the application of new approaches to account for the variability of the solar irradiance across a model grid cell. The team will also investigate the sensitivity of the WRF-Solar v2 forecasts to key parameters used in the model in order to better understand the uncertainty in solar forecasts.

INNOVATIONS

New techniques will be used in WRF-Solar v2 to better account for clouds—particularly fields of broken clouds, details of the size of cloud drops, and atmospheric particles—which will lead to significant improvements in forecasts compared to the previous version. The team will develop a new data-driven treatment of fine-scale variability in solar irradiance that will result in improved forecasting of rapid changes in the solar irradiance. Advanced mathematical techniques will also be used to estimate forecast uncertainty for both intra-day and day-ahead forecasts.