MODEN is a software that simulates different (heterogeneous) energy systems (heating, electricity, hydraulic and others) with 1 ms time step or unlimited life-time preformation simulation. The main emphasis of the MODEN is on its ability to simulate energy systems related to technological material flow for synchronization of energy consumption and industrial output. The software assigns for simulating energy systems of industrial buildings, but can also be used for simulating buildings intended for public-use and dwelling houses. MODEN makes it easy to study physical processes occurring in energy systems. The basis is the theory, according to which any energy system consists of 4 elements: channel (or parameter), port (or flow), object and structure. Each of these elements has a prototype in the library of typical elements. These elements allow users to create the model of the system, which can be corrected with the library of model elements. For example: structure – ventilation system (building, heating system,…..), object – air duct (water pipe, fan, heatexchanger,…..), port – air (water, electricity, gas,….), and channel – temperature (flow rate, pressure, enthalpy and others). Each model (or its part) can be saved as a template for later use. Most templates are created for HVAC application. Movement of templates and model elements is carried out by a “drag & drop” method. The software allows users to connect objects (structures) in the model with equipment and materials data base. In the program, you can make both verification and constructive calculations. The limitations of MODEN are that it cannot work with 3D geometry and BIM, for now.