A heat deflector can be used over the floor registers to direct the heat into the room. Air conditioners consume huge amounts of energy. If you want a cool apartment when you get home from work, connect the unit to a timer and set it to go on a half-hour before your arrival time. Place a window unit in the window of your apartment that is most protected from direct sunlight. Keep windows and doors closed when an air conditioner is running and close draperies or shades on sunny windows, but don't block the cooling unit.
Hot water requires large amounts of energy to heat it.
Flow restrictors also cut amount of hot water used. Try to cut down on the number of times you use your dishwasher. Run only full loads, preferably in the early morning or late evening when energy demands on utility companies are lowest. A product that promotes sheeting action should compensate for thermostat set back. Because single-pane glass is a poor insulator, a great deal of heat can be lost through windows.