Energy does not flow through the wires but along the directions indicated by local Poynting vectors. These vectors are at right angles to BOTH electric and magnetic fields. Hence, the actual location of the energy is the space near the conductors, usually taken up by insulation. Typically, this is NEAR but not INSIDE the wires.

https://en.wikipedia.org/wiki/Poynting_vector#Example:_Power_flow_in_a_coaxial_cable

Here is a typical example using co-axial cable. The GREEN arrows represent the energy flow.



Without the wires, energy transmission is very weak and nearly omnidirectional.