Why we developed the model Biotec. Biomass fired installations are frequently supplied with materials coming from forests or sawmills. Therefore the homogeneity of the fuel, in terms of humidity and size, is very variable. This variability is critical in the network heating installations where the fuel is supplied by different suppliers. Distinctive features of Model Biotec The boiler has a geometry with four turns of smoke in order to maximize the time of permanence of the smokes inside the boiler. This ensures highyields with low emissions in the atmosphere.. The heart of the boiler is the combustion chamber with its big volume that ensures a quiet combustion process with long residence times of the smoke at high temperature. This allows to minimize the emissions starting from the combustion process instead of investing in costly filtering devices after the boiler. An important feature of the combustion chamber is the thick refractory lining made with bricks. This helps the drying of the fuel and makes homogeneous the gas stream entering the heat exchanger even with variable fuel entering the combustion chamber. The combustion chamber is completed with a post combustion chamber which reduces the emissions since it completes the combustion process of the gases. This chamber is also a ‘calm room’ and helps the decantation of dust. Another distinctive feature of the Biotec model in the SP version concerns the feeding of the fuel. We have eliminated all the screws and the star valves. Using proper transport systems and feeding the fuel with an hydraulic pusher the boiler can deal with fuels with irregular and big sizes. The control system of the boiler is another important part of the installation. The developed software ensure a total management of the combustion process to ensure high reliability, yield optimization and low emissions. We have put a specific effort in making the software easy to understand and to be modified by the operator Production The constructional method of the boiler means that by keeping the combustion chamber and changing the heat exchanger it is possible to produce hot water + 95 °C 2 Bar, superheated water + 110 °C 2 Bar, Saturated steam 0,7 Bar.