Energy sharing within EH-enabled wireless communication networks

As energy harvesting (EH) technologies advance, wireless networks will potentially and eminently be powered by harvested energy such that carbon footprints can be reduced. Challenged by the dynamic nature of green energy source availability, various methods have been proposed so that harvested energy can be hoarded for future use or transferred to other devices, such as the storage unit of individual EH devices and energy sharing policy among multiple EH devices within the network. This article provides an overview of the architecture of EH enabled base stations and discusses two energy sharing mechanisms within the wireless communication network: direct energy transfer based schemes (through either the wired power grid or wireless energy transfer), and non-direct energy transfer based schemes (traffic offloading and cooperative transmission). We compare the energy sharing schemes and lay out basic design principles and research challenges on optimizing energy harvesting enabled wireless networks.