An electrosurgical system is disclosed. The system includes an electrosurgical instrument having at least one electrode configured as a first sensor for measuring a voltage drop therethrough and a temperature sensor for a thermal sensor configured to measure a temperature difference across the at least one electrode; and a generator including an output stage coupled to the at least one electrode, the output stage configured to generate radio frequency energy; and a controller configured to determine actual radio frequency current based on the voltage drop and electrical resistivity of the at least one electrode and radio frequency power based on the measured temperature difference and the thermal conductivity of the at least one electrode.