The use of a circulating fluidized-bed (CFB) for power generation is a rapidly growing technology in Poland. The ability of CFBs to burn a wide variety of fuels, while meeting strict emission-control regulations, makes them an ideal choice for burning such fuels as high-sulfur coal, lignite, peat, oil, sludge, petroleum coke, gas and wastes. All these fuels are burned cleanly and economically in CFB boilers without the need for complex scrubbers, catalytic systems or other costly chemical clean-up systems. Presently 19 CFB units are in operation or under construction in Poland; utilizing a wide variety of fuels and wastes. On the basis of gathered performance data, the CFB units met and significantly satisfied all the emission levels. The paper presents the boiler design parameters, design arrangement and specific unique design features of the CFB boilers. A particular concern with the CFB boiler is the low rank brown-coal and the large furnace which had to fit into the limited space of the existing plant. Environmental performances of large-scale CFB boilers are demonstrated. Special emphasis is placed on the experience gained with the largest CFB boilers which have been in operation for more than 4 years. (C) 2003 Elsevier Science Ltd. All rights reserved.