A sensor device used in remote monitoring of waste within a waste container includes a sensor arrangement for monitoring the waste and for generating a corresponding waste-indicative signal, a data processing arrangement for receiving the waste-indicative signal, a wireless interface coupled to the data processing arrangement for enabling the data processing device to emit wireless signals including information derived from the waste-indicative signal, and a power source for providing power to operate the sensor device. The sensor arrangement additionally includes a temperature sensor for measuring a temperature of at least the power source, and the data processing arrangement is operable to be switched from the second reduced-power mode to the first activated mode as a function of the temperature measured by the temperature sensor. This enables power saving and increased service life of the sensor, battery, and the waste container.