A phase-change energy storage module with a turbulent transport fluid is studied. The forced convection due to the turbulent transport fluid is solved with the k–ε model and coupled with the phase-change solution in the phase-change material (PCM). The numerical method is first compared with previous investigations, then conjugate computations for the energy storage module with different cases are conducted. A correlation for the energy storage capacity is derived and its empirical constants are determined by the numerical data. The correlation provides a reference for the module design and parameter optimization.