Impact of Wind Power's Capacity Credit on the System Reliability Index: A Case Study of Southern Sulawesi Systems

Renewable energy resources (RES) generating units are becoming popular in power systems. However, some have intermittent characteristics like wind power plant (WPP). With the presence of intermittent RES, the generation expansion planning (GEP) procedure needs to be modified due to intermittent characteristics. Capacity credit is the instrument to measure the intermittent generating unit in comparison to dispatchable unit. The modification is proposed by calculating the capacity credit sensitivity of different levels of WPP in the GEP procedure so that the contribution can be measured. The proposed method is applied to the Southern Sulawesi System (SSS), which has a peak load of 1,592 MW and abundant wind and hydro power potential for the 2021 - 2030 planning horizon. The energy production and capacity credit calculation are based on the wind profile local data. The result shows that additional 360 MW penetration of WPP will increase the system reserve margin by 16.61% to ensure LOLE 1 day/year. Moreover, the generation cost is increased to 0.09 c$/kWh. In addition, the average capacity credit value is only 8.71% for the current wind potential in SSS.