This paper presents the results of research of the influence of potato pulp content (10, 20, 30%) in a mixture with buckwheat hulls on power consumption of the pellet mill and on the quality of the produced pellets (density and kinetic durability of obtained pellets, as well as their heat of combustion and calorific value), and their elemental composition (dry mass, chlorine, sodium, potassium, phosphorus, and nitrogen). The paper also presents the influence of the pelleting process on changes in water activity of the densified mixture and the obtained pellets. The results of the research show that an addition of potato pulp to pelleted buckwheat hulls caused power consumption of the pellet mill, whereas a reduction of the addition of potato pulp of up to 20% allows to obtain high quality pellets (high density and kinetic durability). The tested mixtures of buckwheat hulls and potato pulp are a material of high energy qualities. (C) 2015 Elsevier Ltd. All rights reserved.