Energy efficiency in telecommunication networks is entering a maturing phase with several solutions proposed by the academic community. While energy specific standardization efforts are still in progress, certain bodies have been working towards advanced specifications including the 3GPP, ETSI, IEEE, IETF and ITU-T. However, a system and service perspective is still missing. This paper addresses such a need centered on the mobile backhaul service, with the architecture defined by the Broadband Forum's Mobile Backhaul Initiative as basis. The objective is, based on current research efforts, to examine and address gaps by combining solutions applicable to specific parts of the systems, like the radio or fixed part, to inspire solution interworking and to encourage further standardization activities.