One of the most critical issues in wireless ad hoc networks is represented by the limited availability of energy within network nodes. Most of the researches focused on the problem of routing issues rather than energy efficiency or prolongation of network lifetime. In this paper, we proposed a multicast power greedy clustering algorithm (termed as MPGC) with the mesh scheme in the multicasting protocol of ad hoc wireless networks. The greedy heuristic clustering partitions a large-scale ad hoc network into a hierarchical cluster structure. Nodes in a cluster determine adaptively their power levels so as to be power efficient. The clusterheads acting as the agents of transmitters/receivers can reduce efficiently bandwidth consumption and complexity of mesh structures. Besides, the mechanism of cluster maintenance can remarkably prolong the network lifetime. The power aware multicasting protocol based on ODMRP executes suitably on the super-nodes topology formed by clusterheads. The results of the simulation show that our scheme achieves better performance for ad hoc networks, in terms of network lifetime and network scalability.