With increasing demand of energy and global issue of sustainable energy resource of thernworld, energy from Biomass is attracting the attention of many researchers as a source ofrnenergy in the world.rnCurrently in Ethiopia about nine new sugar factories are being installed requiring adequaternamount of electrification and energy. The demand of these industries can be met fromrndifferent sources of energy. Gasification can be considered one of these sources.rnIn this work an attempt has been made to develop a procedure for designing a fluidized bedrnreactor that can handle bagasse as a feedstock. By using an appropriate designrnprocedure a complete design of a gasification reactor was studied deeply. The designrnprocedure followed in this thesis is presented in Appendix III.rnThe design work has been categorized into three different parts. The first one deals with thernequilibrium modelling of the fluidized bed to determine the output gas composition. Thernequilibrium model is analyzed with the help of a matlab code giving the volumetric/ molarrncomposition of the product gas. The higher heating value (HHV) found is 2.69 MJ/kg withrnthe moisture content of 15%. A thermal efficiency of 50.78% was obtained which would havernreached about 80% if the sensible heat of the product gas was put under consideration. Thernsecond part of this design work aims at determining the appropriate fluidization parameter ofrnthe reactor since efficient fluidization is required for effective reaction and maximum outputrnefficiency. Parameters like the minimum fluidization velocity, the terminal fall velocity, thernoperational velocities and the bed and freeboard geometries have been determined. The thirdrnpart of this design work investigates the dimension of the reactor, its insulation and thernopenings of the shell and other components of the reactor. The reactor has a 4.2 m outsiderndiameter by 11.3 m height.rnFinally an economic analysis was done on the cost of the gasifier which compares natural gasrnuse as an energy source. The configurations of the reactor and the distributor of the reactorrnare also the core focus of the design work.rnKey words: Biomass, gasification, producer gas, Thermal efficiency, fluidization, higherrnheating value.