Toward green sensor field, power consumption emerges to be an important issue in wireless sensor network (WSN), where sensors are likely to operate on limited battery power. Sensors nearer the sink have to take forwarding traffic load for sensors far away from the sink. Hence nodes of inner shells centered at the sink would deplete their energy budget faster, leading to what is called an energy hole problem (EHP) around the sink. The operational lifetime of sensor network is deteriorated because of such an uneven node power consumption patterns. To model the proposed approach for qualitative analysis, a Petri Net model was developed to configure all relevant system aspects in a concise fashion. On quantitative work, a comprehensive mathematical analysis on power profile has been made in detail. For approaching greener technique, the power consumption patterns are concentrated on the nodes located in the innermost shells of WSN, which dominated the EHP issue. Network simulation results validate that the proposed green scheme indeed provides a feasibly cost-effective approach for lifetime elongation of sensor networks.