transmission line described in clause (iii). (B) Modification of existing transmission property Any electric power transmission line which— (i) was placed in service before the date of the enactment of this section, (ii) is modified after the date of the enactment of this Act in a manner that increases the transmission capacity of such transmission line by not less than 500 megawatts, and (iii) after the completion of such modification, is an electric power transmission line which satisfies the requirements under subclauses (II) and (III) of subparagraph (A)(i). (2) Advanced transmission conductor The term advanced transmission conductor means a transmission conductor technology that uses recently developed technology or materials such as a composite core and such other future advances as determined by the Secretary, in consultation with the Secretary of Energy. (3) Superconducting transmission line The term superconducting transmission line means a transmission line that conducts all of its current over a super-conducting material. (e) Related transmission property For purposes of this section— (1) In general The term related transmission property means any of the following: (A) Transmission property used for interconnection or generator tie-line Any electric power transmission line which is— (i) placed in service after the date of enactment of this section, (ii) primarily used— (I) as a generator interconnection tie line at an associated facility that extends from the secondary (high) side of a generator step-up transformer to the point of interconnection with the host transmission owner from interconnecting new generation resources or facilities to the electric grid, or (II) for network upgrades associated with the interconnection of new generation resources or facilities to the electric grid, (iii) primarily used for one or more purposes described in subparagraph (d)(1)(A)(ii), and (iv) capable of transmitting electricity at a voltage of not less than 230 kilovolts. (B) Grid enhancing technology Any grid