Abstract
Forecast of daily-solar-irradiance curve with higher precision is required for more efficient operation of energy supply system utilizing solar energy. We had developed ERDI method which calculates the daily-solar-irradiance curve from daily-total-insolation forecasted by feed-forward neural network. If the daily-solar-irradiance curve would have been forecasted by “Forecast method for Individual Site (FIS method)”, fiddly procedures such as selection of available data, training of the neural network, and generation of correction curve in ERDI method should be required for every forecast sites. The present paper presents the simpler method, in which a representative model was individually applied for 10 climatic districts, named the method of “Climatic-District Representative modeling in Japan (CDR method)”. CDR method obviously makes it possible that the daily-solar-irradiance curve can be forecasted in the site where the weather data is not available. Forecast errors between CDR and FIS methods were almost similar, which were in the range of 110 to 130Wh/(m2·h) nationwide.
