Abstract
Recently, an ACC-CAES generating system has been developed by applying ACC (Advanced Combined Cycle) technology to a conventional CAES (Compressed Air Energy Storage) system. The ACC-CAES has a potential advantage of high efficiency and high capacity factor over other energy storage. However, advantages of it from the viewpoints of power system operation are not fully revealed because of its peculiar operation characteristics compared with the other energy storage. The characteristics include (1) it requires fossil fuel even in the case of operation using stored compressed air and (2) it has an ACC generating mode as one of its generating states to be used as a conventional ACC generating system while detaching the air storage system. Therefore, it is necessary to examine operation patterns of the ACC-CAES and its contribution to economic operation of a power system. In order to achieve the objective, operation simulations of a power system with ACC-CAES generating systems are needed because operation of energy storage systems such as the ACC-CAES must be studied through an operation scheduling of a power system. This paper develops an optimal daily scheduling method of a power system with both ACC-CAES generating systems and pumped hydro storage systems using two-dimensional dynamic programming. Sensitivity analyses are undertaken with the developed method; the results show that ACC-CAES generating systems tend to be operated as a peak or intermediate power source that bears some similarities to thermal plants or storage systems and, from an operation point of view, they have an economic advantage over pumped hydro storage systems.
