Demand response and pumped hydro storage scheduling for balancing wind power uncertainties: A probabilistic unit commitment approach

Wind generation with a low capacity factor and uncertain nature poses many challenges in grid integration and secure operation of power system. This demands larger quantities of balancing services known as Ancillary services (AS), at cheaper cost in short notice of time. Operating Reserve is a major portion of Ancillary service that can balance the power system with wind integration uncertainties. Utilizing Energy Storage and Demand Response as Operating Reserve, maximum wind energy integration can be achieved in a constrained power system. This paper presents the participation of Pumped Hydro Storage (PH) and Demand Response (DR) as Operating Reserve Ancillary services (ORAS) to mitigate the issues related to wind power integration into the system. Simultaneous scheduling of PH and DR in Energy and Ancillary service markets with wind uncertainties has been attempted by solving Probabilistic unit commitment problem using Lagrangian Relaxation (LR) method. Various cases studied by emphasizing on optimization of operating cost and cost of Operating Reserve are presented and results are found to be encouraging.