Ala. Code § 41-10-517: Exemption from Taxation.

The properties of the authority and the income therefrom, all lease agreements made by the authority and all bonds and promissory notes issued by the authority, the interest thereon, the coupons, if any, applicable thereto, the income therefrom and all lien notices with respect thereto, and all purchases and use of property by the authority shall be forever exempt from any and all taxation in the state or in any county, municipality, or political subdivision thereof.