The work contains selected results of research related to identification modelling of the Polish Power Exchange (Towarowa Giełda Energii Elektrycznej S.A. — TGEE) obtained in MATLAB and Simulink using the System Identification Toolbox and Control System Toolbox. In order to obtain a parametric arx model of the Polish Power Exchange identification was performed using data for the first half year of 2015 (184 days), i.e. for 24 input quantities related to the volume of supplied and sold electrical energy (ee) in each hour of the 24-hour day as well as for individual output quantities related to average prices of supplied and sold ee in consecutive hours of the 24-hour day. 24 discrete parametric models of MISO type were obtained, followed by their transformation into continuous parametric models, and, further, into continuous models in state space. The research was conducted in order to find out whether it was possible to generate a model of the Polish Power Exchange (TGEE) and a metamodel based on the changes of the values of the elements of the model in consecutive hours of the 24-hour day. As a result, changes of elements of matrix A related to changes in the internal organization of the system and selected elements of matrix B related to the change of the control level were analysed. Also, an attempt to analyse the obtained results including state variables was made.