Energy consumption optimization belongs to the main agendas in sustainable industries. Here, cost-saving opportunities in the pulp and paper industry as one of the largest industrial energy consumers worldwide are in the focus. Energy-saving measures are proposed employing a large-scale mathematical model of a paper machine based on mass and energy balances supported by real-time experiments in paper machine operation. The presented measures are based on the optimization of paper stock pumping and a drying section operation. The total energy-saving effect of the four proposed measures accounted for a reduction in specific heat and electricity consumption by more than 2 %. The proposed procedures require no or low investment costs with the overall simple rate of return of less than one year.