Discrete carrier and lattice structures are bonded together to form a lightweight rigid solar panel. The carrier includes a pair of electrically inert face sheets bonded on opposite sides of a thin thermoconductive honeycomb core. The face sheets provide an electrically inert surface for receiving a solar cell array and the honeycomb core forms a heat sink for conducting heat away from the solar cell array. The lattice includes a pair of patterned face sheets having a high elastic modulus bonded on opposite sides of a lattice base. The patterned face sheets provide axial stiffness and the lattice base separates them to provide bending stiffness. By splitting the solar panel into discrete carrier and lattice components, the present invention reduces the weight of existing solar panels by approximately 40% and increases power efficiency by approximately 10%.