An insight into long term operation of an industrial feather gasification facility is presented. The paper discusses the energy balance of the system and its efficiency, the main operational problems encountered during four years of operation of the plant and proposed solutions. The analysis of plant’s long term performance showed that the overall efficiency of the system is 68 % while the efficiency of gasification process solely accounts for approximately 96 %. Further analysis showed that increasing plant’s overall efficiency is possible through further dewatering of the fuel and investing in a more efficient recovery boiler. The most vital operational problems encountered during plant’s operation involve boiler slagging and high emission of nitrogen oxides. It is shown that most of the problems occurring during operation of the plant are associated to the composition of the fuel, which contains high amounts of nitrogen, sulphur, chlorine, alkali metals and alkaline earth metals in comparison to popular woody biomass.