Short-Term Solar Radiation Forecasts in Support of Smart Grid Technology

In order for solar and wind energy resources to supply a greater share of future electricity needs, the US power grid will require new transmission lines to connect power-generation facilities with consumers. The grid will also require smarter controls to better match fluctuating supply and demand cycles. For example, solar energy generation facilities will be impacted by local changes in the cloud distribution. If these intra-day changes could be detected and forecast, the information could be used to order increases (decreases) in power production (consumption) from elsewhere. We have integrated cloud remote sensing and forecast technologies into a system design that can provide the smart grid with such information. The proposed system combines imager data from ground- and space-based remote sensing systems, a cloud forecast model to provide a detailed forecast of various cloud properties for time periods of minutes up to an hour or more, and a radiative transfer model for computation of downwelling solar irradiance in the appropriate waveband at the solar collector. Our paper will describe the components of the forecast system and demonstrate some of its capabilities.