In this work we investigate the use of network coding in 1+1 survivable IP-over-wavelength-division-multiplexing (WDM) networks by encoding the protection paths of multiple flows with each other at intermediate nodes. We study the energy efficiency of this scheme through mixed-integer linear programming (MILP) and a heuristic with five operating options. We evaluate the MILP and the heuristics on typical and regular network topologies. Our results show that implementing network coding can produce savings up to 37% on the ring topology and 23% considering typical topologies. We also study the impact of varying the demand volumes on the network coding performance.