The purpose of the authority shall be to acquire, construct, operate, and maintain or cause to be acquired, constructed, operated, and maintained projects, and to take all other necessary or desirable action, in order to provide or make available an adequate, dependable, and economical alternative supply of bulk electric power and energy and related services for wholesale sales to those municipalities which may desire such supply, and incidentally and so as to take advantage of economies of scale in the provision of economical and reliable wholesale power supply to the municipalities, to enter into interconnection arrangements with other electric suppliers having generation and transmission capabilities, which arrangements provide for sale, purchase, exchange, or transmission of bulk electric power and energy. The authority shall only be authorized, through acquisition or construction of projects, or through interconnection arrangements with others, to provide for the generation, transmission, or distribution of power as provided in this chapter. Nothing in this chapter shall be construed to permit or to cause the authority to acquire or construct, or to maintain and operate any project, or to engage in interconnection arrangements with persons, for any purpose other than those necessary or desirable to provide bulk electric power and energy to municipalities or to effect the sale, purchase, exchange, and transmission of bulk electric power and energy with other electric suppliers pursuant to those arrangements provided in Section 11-50A-8(8). Sales of bulk electric power and energy to municipalities shall only be effected as "wholesale sales" as the term "wholesale sales" is defined in Section 40-21-80(a)(9), as amended, or any subsequent statute of similar import. Nothing in this chapter shall be construed to enable the authority to effect "retail sales" as the term "retail sales" is defined in Section 40-21-80(a)(5), as amended, or any subsequent statute of similar import. The authority shall not, except in the case of dissolution of the authority, disburse any moneys to any municipality participating in the authority, except to reimburse a municipality for amounts advanced to or for the benefit of the authority (with interest) or with respect to overcharges or refunds relating to the authority's costs of and charges for bulk electric power and energy; provided, however, that nothing in this chapter shall prohibit disbursements or payments with respect to the purchase, lease, or other use by the authority of any electric transmission facility or rights-of-way of any participating municipality.