Energy efficiency has become a key concern in industry due to the increased energy costs and the associated environmental impacts. Besides considering single processes/machines, the perspective on process chains and factories as a whole bears further potentials for improvement. In this context, dynamic interactions of different processes as well as auxiliary equipments (e.g. compressed air generation) need to be taken into account when planning and controlling manufacturing systems. This paper presents an innovative energy oriented simulation model for planning of manufacturing systems. A number of industry cases are used to demonstrate the potentials and applicability of the proposed methodology.