N.J. Stat. § 40:62-23
No municipality shall enter into any contract or supply any electricity, gas, steam or other product to any adjoining municipality or the inhabitants thereof, or to any county, unless such municipality, in supplying electricity, gas, steam or other product beyond its corporate limits, complies with all laws, regulations or orders applicable to private corporations, owning or operating any electric, gas, steam or other plant, or distributing or supplying electricity, gas, steam or other product, and unless such municipality pays taxes, including franchise licenses or taxes, the same as would be paid if such plant or equipment were owned by a private corporation, and unless the board of public utility commissioners shall, after notice and hearing, determine and certify that such adjoining municipality or such county is not adequately and properly served by an existing company.
N.J.S. § 40:62-23