2018 年 39 巻 3 号 p. 1-10
In 2012, the Japanese government enforces Feed-in Tariff and promotes the installation of renewable energy into the power system. In particular, photovoltaic (PV) system has been installed in large scale. Net load curve in the power system where large amount of PV system is installed is lower than the conventional load curve in the daytime. In this paper, the long term fluctuation of future net load curves in Kansai area which are estimated by distribution of insolation, forecasting data of PV capacity and observed load data in KEPCO is evaluated. The PV capacity forecasting is based on open data of PV capacity in cities, towns and villages provided by Agency for Natural Resources and Energy.
The result shows that the phased change of the fluctuation properties is occurred as the large amount of PV system is installed into conventional power system. In particular, the load curves in morning turned in decreasing trends from increasing trends. Moreover, the cases of rise in net load during over 6 hours are increased.