N.J. Admin. Code § 18:24-26.4
For purposes of exemption from tax, the purchaser of a solar energy device or system shall issue to the seller an Exempt Use Certificate (Form ST-4) or other approved form. The certificate should indicate on its face that the purchase qualifies for exemption as a solar energy system. The purchaser must insert the address of the property upon which the solar energy device or system will be installed. In those cases where the purchaser is not registered with the Division of Taxation, a New Jersey tax identification number is not required. However, for purposes of verification, either a Federal employer identification number, out-of-State tax identification number for businesses, or a driver's license number for individuals purchasing for personal use is to be furnished and written clearly on the certificate.
N.J. Admin. Code § 18:24-26.4