The present document specifies Key Performance Indicators (KPIs), and associated measurement processes, which reflect the operational energy efficiency of the following digital cellular RAN equipment and supporting infrastructures: - integrated BS; - distributed BS; - BS site. Repeaters are not considered in the present document but are considered for further study (ffs). Energy consumption of user equipment (UE) is outside the scope of the present document, however, how a user equipment (UE) affects a base station energy performance is considered for further study. The KPIs specified: - combine the energy consumption (in the form of electricity) with the volume of data processed; - combine the energy consumption (in the form of electricity) with the coverage area served; - are applicable to the above equipment and also, in certain cases, to the sites accommodating the equipment; - are primarily intended for trend analysis - not to enable comparison between individual BSs unless the conditions of operation are "similar".