Notwithstanding the establishment of certified territories pursuant to this subchapter and the obligations and rights to furnish service within the territory, a retail electric supplier may request another retail electric supplier to render service to one or more electric-consuming facilities where, in the judgment of the requesting retail electric supplier, it would be more economical or otherwise in the public interest for the other retail electric supplier to do so and to enter into a contract for that purpose with the other retail electric supplier.