- 2015 IEEE. In this paper a novel approach is proposed to coordinate wind generators and battery energy storage systems (BESS) to provide both energy balancing and frequency regulation services in electricity markets. A robust optimization based model predictive control (RMPC) scheme is developed to determine the optimal bidding strategy for wind and storage, under uncertainty due to electricity price forecast error. Allowing the wind generation and battery energy storage combination to participate in both the energy balancing and frequency regulation markets increases their joint profits. The performance of the proposed Robust MPC-based optimal bidding strategy is demonstrated through a case study.