20. A unit structure for use in forming a modular data center, the unit structure comprising:an elongated frame structure and a perimeter frame structure forming a rectangular-like subsystem, and adapted to be supported above a floor surface and above a plurality of equipment racks by a plurality of vertical structural support columns;
a roof panel secured to the perimeter frame structure and extending along substantially an entire length of the perimeter frame structure, for assisting in containing cold air within a cold aisle formed below the roof panel;
a ceiling panel secured to the elongated frame structure and spaced apart from the roof panel to define a volume through which hot air may be flowed; and
a pair of panels coupled to and extending vertically adjacent to the elongated frame structure, along opposing sides of the elongated frame such that the panels face one another when in a deployed position extending outwardly from the elongated frame structure, which cooperatively also form the cold aisle therebetween and hot aisles on opposite sides of each of the pair of panels, along substantially an entire length of the unit structure parallel to a length of the unit structure.