Would an opt-in tariff for energy efficiency upgrades include disconnection for non-payment of the program charge?

Yes. Once approved as a tariff, the PAYS charge will be covering costs for an essential utility service, subject to the same disconnection rules as a regular bill.

See: 04 NCAC 11 R12-11 (“Disconnection of Residential Customer’s Electric Service,” which refers simply to the bill and defines payments as “delivery of the amount due to a company.”