The Power Generator Room is the source of all power on the CloudRunner Fortress. It is mostly used to ventilate rooms and activate the wind lifts hich wing-less creatures can use to get to higher spots on the fortress. After Krystal escapes the dungeon and frees Gradabug, the chief engeener of CloudRunner Fortress, Gradabug gives Krystal the Power Room Key to turn on the wind lifts. The Power Room Key does not turn on the power, the three Light Gems, that General Scales has removed and hidden to deactivate the power so Krystal couldn't progress, turn the power on.
The room is full of toxic gas at first but after you activate the power the ventilation of the room begins working again and the gas will go away.