In this paper we develop an energy aware decentralised routing algorithm for adhoc networking of batterypowered wireless microsensors. The useful life of such networks is limited by the battery life of individual sensors and thus the goal of any networking algorithm is to maximise both the lifetime and the coverage of the network, whilst dealing adoptively with sensor failures and changes in network topology. As sensors may be owned and supported by different stakeholders, we view them as selfish agents maximising their own utility. To this end, we develop a mechanism that enables such agents to follow locally selfish strategies which, in turn, result in the achievement of good global performance.