Adtranz designed an innovative energy management system for the new IC-2000 coaches for Swiss SBB. One of the targets was a smoothened operation of air-conditioning, i.e. keeping the air-conditioning system from over-reacting to short-term variations in outside climatic conditions. For example: When the train enters a tunnel, external temperature sensors recognize the steep temperature change as transitory and the control keeps the air-conditioning system from turning on the heating. The same system foresees an extended operation of coach ventilation in the case of overheating due to sunshine through windows. After some technical problems which required developing several versions, the additional energy management system built into the IC-2000-Coach successfully went into service. Due to the energy management system a double deck coach does not consumes more „comfort energy“ than a normal coach (single deck) even though it offers 40 % more seats.