Microgrid for radio access network resilience against power grid outages: Design and operation

The continuous increase in electricity demand, combined with factors such as political instability, cyberattacks, and the rising frequency of natural disasters linked to climate change, poses significant challenges to the reliability and stability of the power grid. Failures in the power grid can have cascading effects on the communication infrastructure, which heavily depends on a stable electricity supply. Enhancing the resilience of computing and communication facilities is therefore essential to support critical aspects of daily life. To address this, we view a group of Base Stations (BSs) in a Radio Access Network (RAN) as consumers and producers within a Micro Grid (MG) equipped with Photovoltaic (PV) panels, energy storage, and interconnected by dedicated power cables for energy exchange. We propose novel RAN resource and energy management strategies designed to maximize RAN Quality of Service (QoS) during Power Grid Outages (PGOs), given the available energy within the MG. Our evaluation considers factors such as the number of BSs in the MG, PV panel capacity, PGO duration, BS traffic profiles, PV panel placement, the energy battery employment, and the geographical extent of the MG. Results demonstrate that the proposed methodology improves QoS, increasing the hourly Managed Traffic by up to more than 300%, an improvement obtained when the MG consists of 4 2-kWp-PV-equipped BSs, compared with isolated 2 kWp PV-equipped BSs, during daily hours. When the MG is implemented, small PV panels (<= 6kWp) perform comparably to large ones (>= 12kWp) in isolated BS setups, making the solution space-efficient. Additionally, performance is mostly unaffected by BS traffic profiles or PGO duration. Effective energy management, accounting for cable losses, and the central placement of PV panels within the MG are critical for optimizing performance.