Energy consumption in general and interference in particular are among the most critical issues in wireless networks. In this paper we present the E-BUM calculus, a Energy-aware calculus for Broadcast, Unicast and Multicast communications in wireless ad hoc networks. We formalize the notions of senderand receiver-centered interference and provide efficient proof techniques for verifying the absence of interference between a specific set of nodes. Keywords--process algebra; manets; interference; topology control