Well, although even google translate couldn't figure out what a kegerator is, I'll try to answer this: Supposing it is just a small fridge, you could use an external thermostat with a wired sensor. You plug that into your wall outlet, plug in the power cable of the fridge, put the sensor in the fridge and set the temperature to switch it on and off. This way the fridge will only get power at the moment the thermostat allows it...