The exploration and harnessing of thermal energy in geothermal tunnels have gradually emerged as a new research topic. This study employs concrete modified with phase-change materials (PCMs) as a pivotal material for geothermal energy tunnels and introduces a temperature-dependent dual-operation mode. The system, functioning in a dual-operation mode of cooling and storage, facilitates adjustment of the tunnel temperature field and extraction of geothermal energy. A comprehensive multi-field coupled finite element model is established, simulating the energy tunnel with PCMs under the proposed operation. Results demonstrate that the temperature-dependent dual-operation mode effectively maximizes the energy storage capacity of PCMs, leading to an annual increase in energy extraction ranging from 0% to 7.73% as the PCM mass fraction escalates from 0% to 20%. Additionally, a parametric analysis is conducted to evaluate the operational efficacy of the system considering the thermal properties of PCMs. Enhanced performance in heat reduction and energy extraction is observed with narrower phase-change temperature windows, and the PCMs with low latent heat show advantages in energy extraction under this operational mode.