Optimal design of bifacial PV system to mitigate duck-curve problem of power system with the UC problem

Abstract

High penetration of photovoltaic (PV) power generation systems is restricted due to the risk of a critical stability decline of the power system. The stability decline has been caused by the power supply/demand imbalance due to the mismatch between photovoltaic power generation and load demand, and exceedance of generators ramp up/down rate with netload variation. This risk is known as the “duck curve problem” in the planning phase. Measures have been proposed, such as demand response (DR), energy storage system (ESS) management, and curtailment of PV generation to mitigate this problem. In this paper, a bifacial PV system of the vertical installation is proposed for duck curve mitigation, which is the simplest and unprecedented approach for the power system. The bifacial PV module’s detailed irradiance model revealed that the proposed method could simultaneously achieves the three characterized peaks; low peak, shifted peak, and bimodal peak. The effect of three characterized peaks on the power system is verified by solving the unit commitment (UC) problem. Besides, the synergistic effect with the ESS management is also verified by the UC problem. Moreover, a multi-objective approach has been applied to the UC problem to assess the proposed PV system and ESS design. Finally, the proposal was clarified that advantages in points of PV installation and total PV output are increased to +34% and 21% respectively, daily operation costs are saved by 2.3%, and reduction of required ESS capacity is achieving to −94% by short cycle charge/discharge operation. This result is concluded that the proposal is in spite of a very simple method, it clarifies the remarkable effects of power system stability, economic advantage, and the possibility of high penetration of renewable energy.