The Assessment of the Salix viminalis wood humidity impact on fuel consumption in Vesko-B heater at the Intech Slovakia heating plant, s.r.o. Hriňová [Graduation these] – Technical University in Zvolen. Faculty of wood Sciences. Thesis supervisor Prof. Ing. Ladislav Dzurenda PhD. Tu in Zvolen, 2017. The energy woodchips from the undergrowth of plantation-like produced fast-growing woods is a new assortment of fuel wood among the RES (Renewable Energy Sources). Perspective fast-growing woody plants grown on energy-plantations in Central Europe include wood clones of Salix viminalis, Populus and Robinia pseudoacacia. The energy properties of fuel wood are largely dependent on its moisture content. Moisture of energy woodchips from energy-plantations using Cut & Chip Technology, that is sawing and chopping, is equal to tree moisture during the vegetation period Wr = 45-55% and for cutting and storage technologies, that is sawing, bundling and natural drying to air-dry state is Wr ≈ 25%. The moisture content of the energy woodchips has a negative impact on both the basic energy properties: combustion heat and calorific value as well as the fuel burning process itself in the hearth of furnace: flame temperature, flue gas volume, flue gas dew point and emission output. The diploma thesis is focused on analyzing the influence of humidity of the Salix viminalis energy woodchips in wet and air-dry condiion for VESKO B heater and efficiency of heat production in the Intech Slovakia s.r.o. Hriňová. The analyzes carried out show that in the annual heat production of 36 720 GJ of heat, the heating plant consumes 4638,5 tons of energy woodchips with an average moisture content of Wr = 40%, resp. 3440 tons of air-dry chips. The reduction in energy consumption of 1 198,5 ton.year-1 for a given heat production is due to the higher calorific value of the air-dry energy woodchips 3,6 MJ.kg-1 and the higher thermal efficiency of the boiler by 1,95%. In financial terms, the decrease in the consumption of energy woodchips despite of the increased price of air-dry energy chips according to the price list od Forests of the Slovac Republic Banská Bystrica by 10.5 € / ton is 20 209,5 € / year.