Faculty of Ocean Engineering and Ship Technology，Gdansk University of Technology,
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In a motor or in a drive system the quantity of power increases in the direction opposite to the direction of power flow. Energy losses and energy efficiency of a motor or a drive system must be presented as functions of physical quantities independent of losses. Such quantities are speed and load of the driven machine or device. But the picture of power stream in a motor or in a drive system is presented in literature in the form of traditional Sankey diagram of power decrease in the direction of power flow. The paper refers to Matthew H. Sankey’s diagram in his paper “The Thermal Efficiency of Steam Engines” of 1898. Presented is also Paszota diagram of power increase in a motor or in a drive system in the direction opposite to the direction of power flow. The diagram, replacing the Sankey diagram, opens a new prospect of research into power of energy losses and efficiency of motors and drive systems. Evaluation of the proposed novel idea presented by Paszota diagram and described in Determining the power stream in motor or in drive system by speed and load of the driven machine or device. Assessment of the novel idea - discovery by taking into account its scientific and technical importance. A new prospect of research into energy losses and efficiency of motors and drive systems is presented in the book Energy losses in hydrostatic drive. Drive investigation method compatible with diagram of power in -crease opposite to the direction of power flow.