In an n-node optical communications system, energy harvesting photodetectors at each node receive extraneous electromagnetic wavelengths that are not used for communication or other purposes by the associated node. The energy harvesting photodetectors convert the unused electromagnetic energy into reusable electrical energy. The harvested electrical energy may be used as auxiliary power at the node or elsewhere in the communication system, or stored in a battery, capacitor, or other energy storage device. The system may be used in an “all-to-all” broadcast and select communication scheme or in some other broadcast and select interconnect system that has extraneous wavelengths at node receivers.