EMPIRICAL EVIDENCE FROM CAISO: SMALL HYDRO RESPONSE TO THE INCREASING SOLAR PV

摘要

To achieve the 100% green electricity goal, we need to understand the relationship betweenrenewable resources in the market and identify clean sources of flexibility to integrate intermittentresources. In this paper we reveal a complementary relationship between small hydro power plantsand solar PVs in CAISO based on the system-wide hourly generation data from 2013-2017.Through a Bayesian structural time series model, we find that when the solar PV increases itsportion in the generation mix by 1%, small hydro will also increase its generation portion by 0.01-0.06%. Such response is more obvious in the morning net demand peak hours and the evening netdemand peak hours. The coefficients are small but statistically significant. The reason behind suchrelationship is the low operation cost, high flexibility, and dispatchability of small hydro in CAISO.Due to its benefit in emission and low LCOE, we suggest considering more small hydro projectsto accommodate the additional solar PV.