Abstract Three laboratory scale gas producers scale gas produces were used to study the gasification properties of rice hulls. The gas producers have an energy output of 15–40 hp and two of them could be run in the downdraft, crossdraft and updraft mode. Several grate designs and combustion air injectors were tested. Physical properties of rice hulls important for the kinetics of gasification and not found in the literature were determined. The design and various modifications made on the gas producers to overcome the unsteady gas generation and the rice hull flow problems associated with the gasification of rice hulls will be reported in Part II. Part I of the report characterizes some of the technical and economical problems associated with the gasification of rice hulls in small-scale gas producers. The rice hulls were gasified in their natural as well as in pelletized form.