This document summarizes an energy efficient clustering algorithm proposed for wireless sensor networks. It discusses the objectives, existing system, proposed system, simulation results and conclusions. The existing system uses a distributed self-organization balanced clustering algorithm (DSBCA) that has uniform cluster sizes and issues with node dropout. The proposed energy efficient clustering algorithm (EECA) forms unequal cluster sizes based on average neighbor energy and selects cluster heads through uneven competition ranges. Simulation results show the heterogeneous EECA provides longer network lifetime, higher efficiency and throughput than the homogeneous EECA.