NSTAR Electric Co. used proceeds from its first-ever green bonds offering of $400 million debentures to support clean energy initiatives, including new solar projects and energy efficiency-related investments.

The 3.25% debentures are due May 15, 2029. "The spread of 85 basis points represents the tightest 10-year new issue spread for an unsecured utility green bond offering, which is tremendous news for our customers, said John Moreira, Eversource Energy senior vice president and treasurer, in a May 22 statement.