This diploma thesis deals with the problems associated with acquisition of experimental data from technological unit for biomass combustion with nominal capacity of 1 MW, with regard to determination of thermal efficiency. In the introduction part, parameters of currently available biomass-based fuels as well as of those with large potential in the future are summarized. Further, a review in the field of biomass combustion technology is given. Biomass boilers are compared according to their technical parameters, function and benefits and drawbacks. In theoretical part methods for determination of thermal efficiency by direct method, indirect method and modified indirect method are described. Main parameters influencing resultant values of efficiency are included into the analysis. In final part an evaluation of real operational data from prototype unit combusting wooden chips is made. Recommendations for further experimental data gathering and their processing with the aim to evaluate thermal efficiency are suggested.

The threat of depletion of fossil fuels is the driving force to diversify energy sources in the Czech Republic respectively in the European Union but also worldwide. One of these potential sources are being biomass boilers. The construction of these boilers has expanded in recent years because of government support for the construction of clean energy sources. Whether it is a burning of clean biomass or just incorporation of biomass to fossil fuels, teh substitution of fossil fuels and biomass boilers are the ideal solution. Their major advantages include significant reductions in emissions, mainly sulfur compounds, organic closure of the cycle of CO2 and disposal costs of spent residue.

he thesis focuses on building of dynamic mathematical model of biomass boiler as a controlled system and the use of this model in practise. At the first part of the thesis the area of energy production using biomass is introduced and the current development at the area of the automatic control of biomass boilers with medium energy output (in units of MW) is described. Although the main topic of the thesis is the construction of model of biomass boiler for control purposes, thesis deals with technology of boilers and principles of its inner processes as well. Creation of the model comes out not only from these important findings, but also from experimental data collected during measurements in real operation. Heat and mass balance calculations were made according to these data and they serve to precise static properties of experimental unit for biomass combustion. Central part of the thesis presents development of the final model that resulted from balance calculations and from step responses of the system obtained by measuring. Built dynamic model is compared with experimental data through simulations in Simulink and verified. At the next part the model of controlled system is completed with control system and closed-loop control circuit is validated and verified by simulation. Then the design of new controller configuration, which improves the quality of control considerably, is presented. At the final part of the thesis, possibilities of other use of the model of boiler are given, both in control theory and in industrial practice.

This thesis deals with a design of a biomass heating plant combinating a Rankin-Clausius cyklus and a CHP unit. The CHP unit fuel is a biogas and the boiler fuel is a wooden chip. The adapted CHP unit regenerates feed-water of the R-C cycles. This design is technicaly and economicalty compared with the Rankin-Clausius cycle without feed-water regeneration by the CHP unit.