The Public Service Commission shall be composed of seven members to be elected by the General Assembly in the manner prescribed by this chapter for terms of four years and until their successors are elected and qualify.

The General Assembly shall provide for the election of the seven member commission and elect members thereto based upon the congressional districts established by the General Assembly pursuant to the official United States Census of 1990. If the number of congressional districts is less than seven, additional members shall be elected at large to provide for a seven member commission.