In this paper, we focus on an essential energy management approach for enhancing energy efficiency (EE) as well as reducing fuel consumption of off-grid cellular networks whose base stations (BSs) are supplied with hybrid power sources including solar PV array and diesel generator (DG). To take the full advantage of PV technology, this paper examines the reliability performance and carbon footprint implications in addition to EE. This paper also investigates the benefits of unevenly harvested green energy sharing mechanism under zero fuel consumption scheme via physically installed resistive power lines taking into account of dynamic nature of renewable energy (RE) generation and traffic arrival density. Furthermore, joint transmission coordinated multipoint (JT-CoMP) user association technique is integrated for achieving higher throughput and EE performance providing the best SINR quality to a connected user equipment (UE). A comprehensive Monte-Carlo based simulation study has been carried out for evaluating EE, EE index (EEI), and energy saving performances in downlink LTE-advanced networks under a wide range of network settings. The results reveal that the proposed system can attain up to 26% energy savings via cooperation mechanism and 48.7% more energy efficient in terms of EEI under peak load over the conventional hybrid paradigm.