An image forming apparatus is disclosed that includes a power storage unit. The power storage unit includes a constant voltage generation part configured to generate a constant voltage from a commercial power supply, the constant voltage generation part being connected to an external apparatus operating by consuming power; a voltage increasing circuit configured to increase the constant voltage generated by the constant voltage generation part; a capacitor configured to store an electric charge supplied from the voltage increasing circuit; a circuit control part configured to control charging of the capacitor; and an output part configured to output power stored in the capacitor, the power having a voltage different from the constant voltage.