A composite structure is provided. The structure is formed of rigid composite material in which particulates or fibers reinforce a polymer matrix. The structure has first and second electrically conductive metallic meshes embedded therein, and respective electrodes electrically connected to the meshes. The first and second meshes are electrically isolated from each other in the composite material so that the meshes can be held at different electrical potentials to each other. In use, an electrical unit can be provided to electrically bridge the first and second meshes such that electrical signals can be transmitted between the electrodes and the electrical unit via the meshes.