This paper highlights the performance of precision hard turning with CBN cutting tools from energy point- of-view with additional tool wear effect. For this purpose several wear tests were performed during which the tool nose wear VBC and the corresponding changes of component forces Fc, Ff and Fp were continuously measured. Based on the measured forces and geometrical characteristic of the uncut layer, specific cutting and ploughing energy were determined for several combinations of cutting parameters. Consequently, changes of energy consumption resulting from tool wear evolution for variable feed rate, depth of cut and tool nose radius were presented.