The document summarizes a PhD student's research proposal on developing an energy-efficient routing protocol for wireless sensor networks. It outlines the objectives to compute high-energy forwarding paths, find non-congested nodes, and determine sink mobility. It then reviews related work on routing protocols and identifies gaps regarding energy and buffer residual status. The literature review covers 18 publications and their applications and limitations. Finally, it provides an outline of the proposed methodology, models, conclusions and future work.