AZ: After years on back burner, interconnection rules back on drawing board

The Arizona Corporation Commission has requested informal comments on a draft version of proposed statewide interconnection rules that apply to DG systems up to 10 MW. The proposed draft rules would:

  • Require customers to pay the full costs of any upgrades required to the system, but allow those costs to be reduced if upgrades provide other readily quantifiable grid benefits.
  • Allow utilities to require the installation of an external disconnect switch.
  • Not require DG customers to obtain additional liability insurance.
  • Embrace a three-level process, including a super-fast-track process for certified inverter-based systems up to 10 kW on radial lines, a fast-track process for systems up to 2 MW on radial lines, and a study process for all other systems.
  • Use fast-track screens that limit aggregate capacity on a distribution circuit to 15% of the annual peak load, and 50% of minimum daytime feeder or line section load.

The ACC specifically seeks comments on the use of IEEE standards and whether utilities should be allowed to force DG customers to install an external disconnect switch.