S.C. Code § 58-40-20
2014 Act No. 236, Section 9, provides as follows:
"SECTION 9. If the application of the provisions of this act to any wholesale electrical contract existing on the date of its adoption is determined to impair unlawfully any term of such contract or to add material costs to either party, then that contract will be exempt from the terms of this act to the extent necessary to cure such impairment or to avoid the imposition of additional material costs."