Regulation intensity assessment of pumped storage units in daily scheduling for renewable energy consumption

To flexibly consume variable renewable energy (VRE), the pumped storage units are facing severe issues induced by regulation duties (e.g., tear, fatigue, vibrations, etc.). This work aims to assess the regulation intensity of the pumped storage unit (RIPSU) for VRE consumption considering both the power grid and units. Firstly, the definition of RIPSU focusing on source-grid coordination is innovatively proposed. Furthermore, a novel assessment model including five important indicators: number of startups and shutdowns, operation duration of power generation, comprehensive utilization hours, regulation mileage, and operation duration in vibration zones, is recommended in VRE systems with pumped storage (PS). Secondly, taking the minimization of VRE consumption deviation as the objective, a day-ahead scheduling model of the Wind-Photovoltaic-Pumped storage hybrid system is established to optimize operation for a better evaluation. Finally, the feasibility of the assessment model is demonstrated by a case study in the Jilin Province of China. The results show that RIPSU will generally increase by approximately 2% to 5% for every 5% rise in VRE consumption. The multiple influencing factors on RIPSU are investigated, including energy consumption demand, resources of VRE, and load demand. The study could support the reliability evaluation in various co-operations of PS and large-scale VRE.