An innovative superconducting DC power cable using high-temperature superconducting wires is introduced. The new cable design is proposed to utilize the longitudinal magnetic field effect that was discovered about a half-century ago. It was shown that the critical current density of a superconducting wire could be significantly increased when the superconductor is in a parallel field configuration. It is empirically known that a force-free structure is attained for the current flowing in the superconductor in this case. In the new cable, the outer layer is twisted in such a way that the shielding current flowing in this region generates a magnetic field that is parallel to the inner conductor. As a result, a force-free structure is realized for the wiring in the inner conductor. It is shown that the current carrying capacity of the proposed cable is dramatically improved in comparison with other cables and that the improvement becomes more pronounced with the increase of the current level.