A structure (26) for supporting an array (22) of solar panels (24) in a solar energy collection system (20) includes a support assembly (42) formed from a rigid subassembly (44). The subassembly (44)includes an elongated truss (68), a base (46) coupled to the truss (68) for attachment to a footing (48), and posts (50) extending from a top edge of the truss (68). The structure (26) further includes torsion tubes (34), each of which is pivotally retained by one of the posts (50) to form parallel rows (32) of torsion tubes (34). A number of rigid subassemblies (44) can be interconnected to further increase the number of rows (32) of the system (20). The solar panels (24) are attached to the torsion tubes (34) to form the array (22), and a drive mechanism (38) pivots the torsion tubes (34) via a single elongated actuator and multiple torque arms (90).