This paper discusses theoretical assets and liabilities of a use of advanced thermal technologies within waste-to-energy (WTE) processing. Gasification and pyrolysis are compared to conventional incineration. Major part of the paper deals with results of gasification experiments: various wastes were gasified within a fluid generator with a circulating fluidized bed. The results were later compared. Lower heating value, composition of the syngas and amount of tar within the syngas were the important observed factors. Experiments were performed at a Biofluid, the pilot facility at the Faculty of Mechanical Engineering in Brno.