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The paper describes experimental and design activities carried out in the framework of the project named “Centre of Excellence on Clean Energy”, led by Sotacarbo and funded by the Regional Government of Sardinia. The project aims at acquiring specific experimental data and reliable information to define design and operating criteria for the development of a bubbling fluidized bed gasifier (BFBG) for small-scale commercial applications (about 100 kWe) with natural biomass, to be located in the Sotacarbo Research Centre. To this end, the project involves institutions and companies active in the field of biomass gasification in the last ten years. Reliable data for the design of the new plant have been obtained by a pilot scale BFBG, having a maximum potentiality of about 100 kg/h of biomass, located at the Amra research centre in Caserta. It has been operated by the research team of the Second University of Naples, with two types of lignocellulosic biomass: wood chips of pine and of a mixture of pine, fir and beech. The tests have been carried out under conditions of thermal and chemical steady state, with a bed of olivine particles, pre-heating the fluidizing air stream but without any heat input along the bed. The operating conditions have been changed to obtaining an exhaustive characterization of the biomass gasification behaviour under the conditions of interest for the design of the new gasifier. The fluidization velocity varied from 0.5 m/s to 0.8 m/s while the biomass flow rate has been modulated to obtain equivalence ratios in the range 0.25-0.38. The experimental results provided a complete characterization of the syngas, bed material and entrained fines collected at the cyclone outlet. The main relationships of fluidization engineering processed these results to support the process design of the new gasifier. The BFBG process of the tested biomass appears technically feasible, yielding a syngas of valuable quality for energy applications in an appropriate plant configuration.