Ala. Code § 37-4-28

No plant, property or facility for the production, transmission, delivery or furnishing of gas, electricity, water or steam shall be constructed, except ordinary extensions of existing systems in the usual course of business, until written application is first made to the commission for the issuance of a certificate of convenience and necessity, and the issuance by the commission of such certificate. Upon the filing of any such application, and after a public hearing of all parties interested, the commission may, or may not, in its discretion, issue such a certificate of convenience and necessity, and if issued, may prescribe such conditions upon the issuance as it may deem advisable.