Based on the model of atoms crossing a microcavity where the microcavity interacts with a nonequilibrium bath consisting of a series of two-level atomic pairs,we inve stigate the energy contribution of quantum coherence in atomic pairs to the cavity field.We derive the master equa tion of cavity field evolution and provide the energy of cavity field at steady state when each independent two-le vel atomic pair is in the general state,i.e.,all the elements density matrix being nonzero parameters.We demons trate that the quantum coherence in each aomic pairs of bath serving as the role of thermodynamic resource,i.e.,th e quantum coherence could enhance the cavity′s energy extracted from the bath.Meanwhile,we also analyze the cha racteristics of all the quantum coherent elements (the nondiagonal elements of density matrix of two-level atom ic pair) for the energy contributions to the cavity field.The paper could provid e the reference for the design of quantum photon engine with high efficiency.