A hybrid composite fiber for transmission of data and power, comprising: a dielectric waveguide (110; 210) adapted to transmit data from an end (102; 202) of the fiber to another end (104; 204) of the fiber via electromagnetic radiation with a wavelength above the optical spectrum; and an electrical conducting element (120; 220) disposed around the dielectric waveguide (110; 210) between said ends of the fiber to electromagnetically shield the electromagnetic wave propagating inside the dielectric waveguide (110; 210); wherein the electrical conducting element (120; 220) is adapted to be coupled to electrical potentials at each end of the fiber for carrying an electrical current between said ends of the fiber; characterized in that the electrical conducting element includes one or more electrical wires adapted to carry an electrical current between said ends of the fiber that are wrapped around the dielectric waveguide from one end to the opposed end of the fiber at a predetermined spacing (d) so as to partially cover the dielectric waveguide ; or the electrical conducting element includes a plurality of conductive parts (250; 255) adapted to carry an electrical current between said ends of the fiber and which are disposed side-by-side and at a predetermined spacing (D) around a perimeter of the dielectric waveguide so as to partially cover the dielectric waveguide , the predetermined spacing (D) between each of the plurality of conductive parts (250; 255) forming a gap that electrically isolates the plurality of conductive parts (250; 255) from each other; wherein the predetermined spacing (D) is selected based on a wavelength of electromagnetic radiation to be transmitted through the dielectric waveguide (110; 210) so as to prevent electromagnetic coupling of the transmitted electromagnetic radiation with external agents. a dielectric waveguide (110; 210) adapted to transmit data from an end (102; 202) of the fiber to another end (104; 204) of the fiber via electromagnetic radiation with a wavelength above the optical spectrum; and an electrical conducting element (120; 220) disposed around the dielectric waveguide (110; 210) between said ends of the fiber to electromagnetically shield the electromagnetic wave propagating inside the dielectric waveguide (110; 210); wherein the electrical conducting element (120; 220) is adapted to be coupled to electrical potentials at each end of the fiber for carrying an electrical current between said ends of the fiber; characterized in that the electrical conducting element includes one or more electrical wires adapted to carry an electrical current between said ends of the fiber that are wrapped around the dielectric waveguide from one end to the opposed end of the fiber at a predetermined spacing (d) so as to partially cover the dielectric waveguide ; or the electrical conducting element includes a plurality of conductive parts (250; 255) adapted to carry an electrical current between said ends of the fiber and which are disposed side-by-side and at a predetermined spacing (D) around a perimeter of the dielectric waveguide so as to partially cover the dielectric waveguide , the predetermined spacing (D) between each of the plurality of conductive parts (250; 255) forming a gap that electrically isolates the plurality of conductive parts (250; 255) from each other; wherein the predetermined spacing (D) is selected based on a wavelength of electromagnetic radiation to be transmitted through the dielectric waveguide (110; 210) so as to prevent electromagnetic coupling of the transmitted electromagnetic radiation with external agents. <EOS>