Aluminium die casting plants offer great potential for optimisation in terms of production and energy efficiency, which can be demonstrated by simulation. However, real companies often have a poor data basis for complex simulation. Based on a complex model, simplified simulation models are designed that are compatible with a low amount of data acquisition. These are described in this paper and tested on different scenarios. One scenario is the variation of downtimes of production machines. Considerable savings in computing time can be reached with still plausible results in terms of material and energy consumption.