An optical line terminal (OLT) comprising a processor configured to process a first power consumption data associated with a first optical network unit (ONU) for a plurality of wavelength channels in a multiple-wavelength passive optical network (PON), and select a first target wavelength channel from the plurality of wavelength channels based on the first power consumption data in order to reduce power consumption at the first ONU, and a transmitter coupled to the processor and configured to transmit to the first ONU a tuning control message instructing the first ONU to tune to the first target wavelength channel.