(1) A person who is subject to tax under this chapter on gross income from sales of electricity, natural gas, or manufactured gas made to an aluminum smelter is eligible for an exemption from the tax in the form of a credit, if the contract for sale of electricity or gas to the aluminum smelter specifies that the price charged for the electricity or gas will be reduced by an amount equal to the credit.
(2) The credit is equal to the gross income from the sale of the electricity or gas to an aluminum smelter multiplied by the corresponding rate in effect at the time of the sale under this chapter.
(3) The exemption provided for in this section does not apply to amounts received from the remarketing or resale of electricity originally obtained by contract for the smelting process.