This paper contains a discussion of electric power requirements in Native American communities in general, focusing on the Navajo Nation in Arizona in particular. The discussion includes the feasibility of achieving sustainability of the electric energy supply. The work described includes results and comments developed by a group of secondary school educators in Arizona. Details of photovoltaic residential electric supplies are described. Native American cultural perceptions and issues are included in a format which may be unusual for an engineering paper, but hopefully give insights to factors that influence power engineering decisions on American Indian reservations. A conceptual view and suggested model and parameter identification approach to the fuel depletion curves are also described.