This study presents a model for the optimization of machining parameters for the minimum energy consumption in a multi-pass turning operation. The model takes into account finishing and roughing passes separately for the energy optimization followed by the dual optimization of the energy functions for a combination of one finishing pass and multiple roughing passes to finish a desired diameter on a cylindrical workpiece. The parametric constraints, tool-life constraints and operational constraints are enforced in the model before optimizing the energy function using non-linear programming. The model is applied to an example case for the optimization. The effects of total-depth-to-be-removed, material removal rate and tool replacement time are evaluated on the optimal parameters for sustainable machining.