Economic feasibility of a wind-battery system in the electricity market with the fluctuation penalty.

As the rapid development of wind energy and electricity markets, wind farms (WFs) in mounting numbers join the electricity markets such as spot and regulating markets, etc. The large-scale integration of WFs into the power system may threaten the safe and stable operation of power systems due to the inherent fluctuation nature of wind power, and as a consequence, the WFs may be penalized by the grid operator in the electricity market. In this case, WF owners will take actions to reduce the fluctuation and one of the promising strategies is to integrate battery storage system (BSS) into the WFs. Base on this idea, a novel framework of considering fluctuation penalty (FP) in the Danish spot market which is the electricity market investigated in this study is firstly proposed. The economic feasibility of integrating BSS into a WF in the spot market is analyzed and a bi-level programming is adopted to design the sizing of the BSS based on Return on Investment (ROI). This research also analyzes the impact of various fluctuation penalties and subsidies on the ROI. It is found that the net revenue of integrating BSS into a WF can increase by 15.8% and the FP can reduce by 64.9% in the spot market with the FP. [ABSTRACT FROM AUTHOR]