Smart Grid in radio access networks (SG-RAN): Smart energy management at cell-sites

In this paper, we research on an interdisciplinary field of how the Smart Grid can help energy cost reduction in wireless communications. We study how the advances in the Smart Grid such as the information on predicted electricity price can be used to help reduce the energy cost of the cellular networks. Particularly, smart energy management at cell-sites is studied to minimize the electricity cost for mobile operators by leveraging time-varying electricity prices in the Smart Grid. We first propose a theoretical framework to optimally manage energy at a single cell-site (without and with energy harvester, respectively) by judiciously choosing which power source (the Power-Grid or a storage-battery) to use, when and how much to use in the cell-site; as well as controlling when and how much to charge the storage-battery. Moreover, we extend the framework from a single cell-site to a network including multiple cell-sites with different electricity prices or energy storage capacity, etc., where cell association, power control, and scheduling can be jointly considered to provide load shifting and cell ON/OFF to achieve mobile network operation with the lowest electricity cost.