It is hereby declared to be in the public interest of the State of Nebraska that agencies be empowered to participate jointly or in cooperation with municipalities and other public agencies in the establishment and operation of facilities for the generation or transmission of electric power and energy located within or outside this state in order to achieve economies and efficiencies in meeting the future electric energy needs of the people of the State of Nebraska. In furtherance of such need and in addition to but not in substitution for any other powers granted such agencies, each such agency shall have and may exercise its power and authority to plan, finance, acquire, construct, own, operate, maintain, and improve electric generation or transmission facilities located within or outside this state jointly and in cooperation with one or more other such agencies, cities, or villages of this state which own or operate electrical facilities, or municipal corporations or other governmental entities of this or other states which own or operate electrical facilities. The powers granted under this section may be exercised with respect to any electric generation or transmission facility jointly with the powers granted under any other provision of sections 18-412.07 to 18-412.09 and 70-628.02 to 70-628.04.