A blank screen saves energy, screen savers do not save energy. The sleep mode is the next best energy saving device. The reduction is from 300W to 30W. Turning OFF the monitor, when idle, is best. Printers Don't turn on your printer until it is needed. Before printing in color, make a black and white copy to edit.
Laser printers require more energy than inkjet or deskjet printers.
Use the power save mode. A printer that will print on both sides of the page saves paper. Fax Machines Reuse one-sided office paper in the fax machine. Use Post-its to save a cover sheet. Deactivate the confirmation page usually generated after a fax is sent.