An innovative thermal switch device using a thin metallic film electrostatically actuated by an electrode mainly conceived for caloric cooling is studied. Our study focuses on the characterization of the thermal conductance at the interface for the "on" and "off" states. Our setup uses the current passing through the metallization of the film as a heater while the temperature is deduced from the measurement of its electrical resistivity. Using a thermal diffusion model and our measurements, we deduce the on and off states thermal conductances and we achieve an on/off conductance ratio of 10 3. Lastly, we use a simple finite-time thermodynamic model to estimate the efficiency at maximum power we would obtain by integrating a standard electrocaloric film in our thermal switch. The result is a micro-refrigerator working at 85% of Carnot efficiency with a power density of 228 W g −1 which is far more than what it have been currently demonstrated.