Currently run-time reconfigurable hardware offers really attractive features for embedded systems, such as flexibility, reusability, high performance and, in some cases, low-power consumption. However, the reconfiguration process often introduces significant overheads in performance and energy consumption. In our previous work we have developed a reconfiguration manager that minimizes the execution time overhead. Nevertheless, since the energy overhead is equally important, in this paper we propose a configuration memory hierarchy that provides fast reconfiguration while achieving energy savings. To take advantages of this hierarchy we have developed a configuration mapping algorithm and we have integrated it in our reconfiguration manager. In our experiments we have reduced the energy consumption 22.5% without introducing any performance degradation.