As a means of raising the funds needed from time to time in the acquisition, construction, equipment, maintenance and operation of any facility, building, structure or any other matter or thing which the Authority is herein authorized to acquire, construct, equip, maintain or operate, all or any of them, the Authority may issue bonds, payable both as to principal and interest from project income from any source, and the powers and authority granted to counties, cities, school districts and other political subdivisions of the State are hereby extended to and made available to the Authority. All revenue bonds issued by the Authority to obtain funds for the acquisition, construction, equipment, maintenance and operation of its properties and facilities shall be issued in accordance with the provisions of §§ 6-21-10 to 6-21-570 and all conditions, restrictions and limitations imposed by such sections, as amended, shall be observed by the Authority in the issuance of such bonds, except as follows:

(1) A pledge of the net revenues derived from the operation of its properties and facilities, all or any of them, rather than its gross revenues, may be made; and

(2) Free service may, in the discretion of the Authority, be afforded to the State of South Carolina or the United States of America, or any agency, political subdivision, department, corporation or instrumentality thereof, by any property or facility of the Authority to acquire, construct, equip, maintain and operate which funds were obtained from the revenue bonds purchased and held by a State or Federal agency, provided such free service is with the consent and at the request of the State or Federal agency then holding the whole of such revenue bonds.