摘要： The energy storage and fossil-backup (fossil-hybridization) systems of a concentrating solar power plant (CSP) provide a continuous production of energy all over the year and satisfy the grid demand even when the sun is not shining. One could ask about the behavior of the energy production, or the levelized energy cost, as a function of the energy storage and of the fossil-hybridization in such plants. This paper tries to answer this question. For this task, there have been performed numerous simulations on a central receiver plant with a fixed nominal power, varying the storage capacity and the level of hybridization. The results showed that these variables impact differently. For the thermal storage, from capacities ranging from 0h to 24h, there is a specific intermediary capacity, 15h, in which the levelized energy cost is minimum. But for the fossil-hybridization, this energy cost always decreases with the increment of the hybrid level. The results also showed that, if a given energy production is supported by a certain level of hybridization, its energy cost would be less than that supported by a storage system. This is due to the relatively high investment costs related to the storage system, and the relatively low cost of fuel.