By means of a sophisticated micro-processor, this device drastically reduces the energy consumption of fridges and refrigerating groups. It adjust in continuous the compressor revolution number and, by means of a special sensor, it detects the refrigerator air temperature thus cooling food a bit more than necessary when the boat engine is on or when the boat is connected to the dock. During navigation, it exploits the food surplus frigories to reduce the compressor operation with an energy saving of about 50%. This device can match any fridge or refrigerating group. The kit includes: panel with micro-processor, adjustable potentiometer, air sensor.