Electric utility's exclusive rights in assigned service area--Connecting facilities in another area

Each electric utility has the exclusive right to provide electric service at retail at each and every location where it is serving a customer as of March 21, 1975, and to each and every present and future customer in its assigned service area. No electric utility shall render or extend electric service at retail within the assigned service area of another electric utility unless such other electric utility consents thereto in writing and the agreement is approved by the commission consistent with §