S.C. Code § 6-23-160
The joint agency is hereby authorized to fix, charge, and collect rents, rates, fees and charges for electric power and energy and other services, related to the generation, transmission and sale of electric energy. For so long as any bonds of a joint agency are outstanding and unpaid, the rents, rates, fees and charges shall be so fixed as to provide revenues at least sufficient, together with other available funds, to pay all costs of and charges and expenses in connection with the proper operation and maintenance of its projects, and all necessary repairs, replacements or renewals thereof, to pay when due the principal of, premium, if any, and interest on all bonds payable from said revenues, to create and maintain reserves and comply with such covenants as may be required by any resolution or trust agreement authorizing and securing bonds, and to pay any and all amounts which the joint agency may be obligated to pay from said revenues by law or contract.
Any pledge made by a joint agency pursuant to this chapter shall be valid and binding from the date the pledge is made. The revenues, securities and other moneys so pledged and then held or thereafter received by the joint agency or any fiduciary shall immediately be subject to the lien of the pledge without any physical delivery thereof or further act, and the lien of the pledge shall be valid and binding as against all parties having claims of any kind in tort, contract or otherwise against the municipality or joint agency without regard to whether such parties have notice thereof.
S.C. Code § 6-23-160