Empirical Evidence from Bayesian Structural Time Series Model: Small Hydropower Responses to Increasing Solar PV in CAISO

摘要

To achieve the 100% green electricity goal,we need to understand the relationship between renewable resources in the market and identify clean sources of flexibility to integrate intermittent resources.In this paper we reveal a complementary relationship between small hydro power plants and 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 its portion 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 net demand peak hours.The coefficients are small but statistically significant.The reason behind such relationship 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 projects to accommodate the additional solar PV.