Time and wavelength division multiplexed passive optical network (TWDM-PON) standards dramatically increase the performance of PON systems and address ever-increasing demands for bandwidth. However, these schemes increase the complexity and energy consumption of PON systems because they exploit multiple wavelengths, which requires multiple transceivers in the optical line terminal (OLT). In this paper, we propose to integrate software-defined networking (SDN) into standard PON architectures to facilitate an orchestrated energy-efficient operation in which the SDN controller dynamically provisions the number of wavelengths, link-rates, and timeslot assignments depending on the global traffic conditions. The simulation results show that the proposed architecture and mechanism improves the energy-saving performance of OLTs if the traffic load is less than 80%, while guaranteeing the quality of service requirements in terms of the mean packet delay, jitter, queue length, throughput, and packet loss ratio.