N.H. Rev. Stat. Ann. § 33:6-b

Municipalities, other than school districts and counties, may incur debt for energy production projects including the reconstruction or enlargement of a municipally owned utility; the manufacture or furnishing of light, heat, power or water for the public; the generation, transmission or sale of energy ultimately sold to the public; or the construction, enlargement, or improvement of small scale power facilities, as such facilities are defined in RSA 374-D:1; by the issue of bonds or notes authorized under this chapter, RSA 374-D, and as otherwise provided by law. Any debt incurred for this purpose shall be outside the debt limit prescribed in this chapter. Such debt shall at no time be included in the net indebtedness of any municipality for the purposes of determining its borrowing capacity.