No bonds shall be issued by any municipality for the purpose of financing the construction of a new electric light and power plant or distribution system, for the purchase or acquisition of an existing electric light and power plant or distribution system, or for the construction of extensions to any electric light and power plant or distribution system in excess of twenty percent of the book value thereof as shown by its books, unless the question of issuing such    bonds has been submitted to a vote of the qualified electors of the municipality as provided in section 40-35-07 and has been approved by a majority of such electors voting on such question.