Multi-directional expandable transformer house

A mobile expandable structure can expand both outward, from at least one side thereof, and rearward, from a back side thereof. When expanded, the mobile expandable structure can provide an expansion of about 2.5 to about 3 times the original living space provided by the main structure. The structure may be on an electric chassis and the structure can include a solar array that is disposed, in the stowed configuration, over the main structure. The solar array is expandable to cover some or all of the expansion sections when in the expanded configuration. The expansion sections can include pivotable floor members that pivot downward upon expansion of each 10 expansion section. Side walls of the side expansion may be unfolded to provide sides of the side expansion section.