Any joint authority created pursuant to sections 70-1401 to 70-1423 which is itself engaged in the generation, transmission, or sale of electrical energy, at wholesale or retail, or which is itself engaged in the construction, maintenance, expansion, improvement, or operation of a power generating plant or other facility for the production or transmission of electrical energy shall comply with the restrictions contained in Chapter 70, articles 10 and 13, and the provisions of sections 70-624 to 70-680.