N.C. Gen. Stat. § 117-20

No corporation may sell, mortgage, lease or otherwise encumber or dispose of any of its property (other than merchandise and property which lie within the limits of an incorporated city or town, or which shall represent not in excess of ten percent (10%) of the total value of the corporation's assets, or which in the judgment of the board are not necessary or useful in operating the corporation) unless

(1) Authorized so to do by the votes cast in person or by proxy by at least two-thirds of its total membership, and

(2) The consent of the holders of seventy-five per centum (75%) in amount of the bonds of such corporation then outstanding is obtained.

Notwithstanding the foregoing provisions of this section, the members of such a corporation may, by the affirmative majority of the votes cast in person or by proxy at any meeting of the members, delegate to the board of directors the power and authority (i) to borrow moneys from any source and in such amounts as the board may from time to time determine, (ii) to mortgage or otherwise pledge or encumber any or all of the corporation's property or assets as security therefor, and (iii) with respect to Electric Membership Corporations only, to sell and lease back any of the corporation's property or assets.