Design of energy efficient wireless networks is the primary research goal for evolving billion device applications like Internet of Things (IoT), smart grids and Cyber Physical Systems (CPS). Energy efficient models can reduce megawatts of power through out globe thereby reducing carbon foot print by improving overall network lifetime of large scale networks. Recent advances in physical layer have optimized energy consumption of IEEE 802.15.4 Physical layer, but energy efficiency of MAC and network layers is also essential to realise Green wireless networks. Though anycast multi-hop communication is initiated by many recent researchers by obtaining reliability, delay and energy expressions, still there is no model that captures relay nodes state wise behaviour effectively. In this paper a new energy model with 3-dimensional Markov MAC model with generalized anycast routing and state behaviour is proposed and developed for asynchronous wireless ad hoc networks. Proposed state behaviour of node model has consideration of MAC and network parameters like minimum backoff exponent, maximum backoff stages and retries along with network parameters like packet length, wake up rate, Sleep, Idle-Listen, Active-Tx and Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) states. Results show that total energy of derived model depends on many network and MAC parameters. Affect of most of the considered parameters are analysed with simulation results. Total energy of the multi-hop network reduced to 25% with variation in minimum backoff exponent and increased by 45% with increase in packet length. It is observed that derived analytical energy model better fits with most of the parameters that affects energy. © 2014 IEEE.