(1) A utility may:
(a) purchase conservation from a person or private firm; or
(b) directly engage in conservation investments.
(2) The conservation purchases or investments provided for in subsection (1) are subject to approval by the commission.
(3) Cost-effective conservation measures approved by the commission may, at the customer's discretion, be installed by:
(a) a person or a private firm;
(b) the customer; or
(c) the utility.