In this paper, an energy-aware routing algorithm based on renewal process is proposed to choose highly competitive solutions for routing performance in cognitive radio ad hoc networks (CRANs). Moreover, we propose a new medium access scheme through spectrum forecast for secondary users to access the primary users¡¯ channels. Thereby, the proposed algorithm can allow selected routes corresponding to minimum energy possible between source and destination nodes in cognitive radio networks. The contribution of this paper is achieved through energy utilized in the network. Simulation results show that energy consumption, system throughput and end-to-end delay can be optimized by using proposed algorithms.