Recently, a large number of renewable energy (RE) sources such as wind farms (WFs), photovoltaic generations (PVs) have been introduced to power systems as a solution for the worldwide environmental issue. On the other hand, with the deregulation of the electric power industry such as the full liberalization of retail sector, power producer and suppliers who own RE sources have traded the generated electricity in the electric market. However, power outputs of RE sources fluctuate every moment and it is impossible to predict the power output perfectly. Thus, to operate RE sources according to the generation schedule notified in the market while suppressing their power output fluctuation, cooperation of energy storage systems with RE sources are required. This paper proposes a method for determining the scheduled generation of WFs by cooperating the predicted WF power output and heat pumps (HP)/biogas engine generator (BG) heat supply system (HP/BG heat supply system) which is a new energy storage technology developed by the authors. The proposed methods consist of two steps. In the first step, optimal operations of HP and BG are determined by utilizing the predicted WF generation so that the flexibility of HP/BG system can be ensured. In the second step, the operations of HP and BG are modified based on actual WF outputs including predicted errors. The validity and effectiveness of the proposed method are investigated through some computational simulations using MATLAB.