Renewable energy could be the key for sustainable next-generation cellular networks. The authors' approach would let mobile operators feed base stations in a heterogeneous network using renewable energy sources. The authors compare their method to a classical grid-powered solution. They evaluate costs and CO ₂ emissions savings for different scenarios to demonstrate that properly powering a heterogeneous network with renewable energy can be a sustainable and economically convenient solution.

The increasing penetration of renewable sources in power systems yields various issues in network operation. Most of them are related to uncertainties of energy production. In particular, the variability of wind source does not allow for accurate forecasting of power generation. Production plans may not be accomplished, incurring penalties for system unbalance. For this reason, the use of an energy storage system can improve integration of wind energy in production planning and dispatch. In this paper, an approach for planning and operating an energy storage system for a wind farm in the electricity market is proposed. To this purpose, electrochemical batteries are employed to compensate for generation variations in order to set up a reliable hourly delivery profile, complying with market requirements. The delivery plan can be settled according to energy prices, as well. Moreover, an economic feasibility analysis is carried out on the combined wind-storage system.