Patent ID: 8008892

Claim:
An image forming apparatus comprising: a step-down unit that steps down a voltage based on a commercial power supply; a charge accumulating unit that is chargeable and dischargeable and is charged by electric power output from the step-down unit; a load that one of electric power output from the charge accumulating unit and the electric power output from the step-down unit is supplied; a first switching unit that switches whether to supply the electric power output from the charge accumulating unit to the load or to supply the electric power output from the step-down unit to the load; a storing unit that stores a condition of an output sheet to which an image is formed and an accumulated power use time for a plurality of image forming operation modes or image forming operation conditions, the plurality of image forming operation modes or image forming operation conditions each requiring output of electric power from the charge accumulating unit; and a control unit that controls the load and the first switching unit based on the condition of the output sheet and the accumulated power use time corresponding to a predetermined image forming operation mode or image forming operation condition.