Increasing sustainability and resiliency of cellular network infrastructure by harvesting renewable energy

The carbon footprint of cellular base stations is a source of concern not only because of their power consumption, which accounts for more than half of all of the cellular infrastructure, but also because of the large rate of growth in their deployment. This article discusses how the use of harvested renewable energy can contribute to solving this problem. The article also addresses the challenges associated with harvesting wind and solar energy, namely the variability in available energy and the large physical footprint of energy harvesters. This article explains that these challenges can be better addressed by jointly considering the harvested energy availability and the dynamic characteristics of base station power consumption. A realization of this approach is the recently introduced idea of a "sustainable wireless area" that integrates energy harvesters and a group of base stations in a microgrid architecture. This architecture enables an integrated harvested energy-cellular traffic management technique that shapes the traffic serviced by a base station based on the predicted availability of renewable energy. As a result, longer periods of operation powered from renewable energy are achieved while degradation of the users\´ qualityof- experience (QoE) is minimal and occasional. This article also explains how harvested renewable energy also increases the resiliency of cellular networks because they do not depend on lifelines for operation.