The modelling of breakage in compression breakage has traditionally been done using population balance modelling, and the research has been developed over the last decades into advanced dynamic models. This paper presents a model for predicting particle size distribution and energy consumption. The particle size distribution model is derived using a first-order differential equation for how the coefficient of variance depends on the compression length. The coefficient of variance model is combined with a bimodal Weibull distribution to predict the cumulative size distribution. The power consumption is modelled in a similar way using Weibull analysis to determine the relationship between power consumption and the coefficient of variance.