N.Y. Comp. Codes R. & Regs. tit. 20 § 38.2
If during a taxable year a taxpayer has received a reduction in the rate charged for gas, electricity, steam, or water sold, or gas, electric, steam, or water service rendered, pursuant to section 186-a (8) of the Tax Law, based upon a certification as to the claiming of a credit under section 210 (19), section 1456 (e), or section 1511 (g) of the Tax Law, and it is finally determined that such taxpayer is not entitled to such credit in any part, such taxpayer shall pay a penalty in an amount equal to such reduction in cost, with interest from the last day of such year at the underpayment rate prescribed in section 1096 (e) of the Tax Law (see Part 2393 of this Title). The Commissioner of Taxation and Finance has the power, in his or her discretion, to waive, reduce, or compromise such penalty. For purposes of this section, the term finally determined means a determination made final when all administrative remedies have been exhausted and the determination is no longer subject to judicial review.
N.Y. Comp. Codes R. & Regs. Tit. 20 § 38.2