| Popis: |
This chapter discusses the use of ground-based visible wavelength imagery for short-term forecasting of solar-power output. It begins with selected applications of short-term forecasting to both transmission- and distribution-scale generation. The hardware used in sky-imaging systems is next presented, providing technical and historical information on system optics and sensory equipment (e.g., charge-coupled devices). A high-quality sky-imaging system designed by the authors (the USI) is then briefly examined. The core of the chapter consists of describing sky-imagery analysis techniques, followed by their application to a large solar-power plant. The techniques used to detect clouds, determine their height, and estimate their motion are explained. Application of these methods to generate a power forecast is presented in a case study of a 48 MW solar-power plant, for which a week of data was analyzed. The results are discussed and ideas for improvement are presented. Finally, recommendations for advancing ground-based visible-wavelength imagery and forecast performance are presented. |
