Iowa Administrative Code › Agency 199 - Utilities Division › Utilities and Transportation Divisions › Chapter 45 - Electric Interconnection of Distributed Generation Facilities › Rule 199-45.9 - Level 2 Expedited Review

Current through Register Vol. 47, No. 3, July 24, 2024
A utility shall use the Level 2 review procedure for
				  interconnection requests that meet the Level 2 criteria in subrule 45.7(2). A
				  utility may not impose additional requirements for Level 2 reviews that are not
				  specifically authorized under this rule or rule
				  199-45.3
				  (476) or subrule 45.5(9) unless the applicant agrees.
(1) The utility shall evaluate the potential
				for adverse system impacts using the following screens, which shall be
				satisfied:
a. For interconnection of a
				proposed distributed generation facility to a radial distribution circuit, the
				total distributed generation connected to the distribution circuit, including
				the proposed distributed generation facility, may not exceed 15 percent of the
				maximum normal load normally supplied by the distribution circuit.
b. For interconnection of a proposed
				distributed generation facility within a spot network, the proposed distributed
				generation facility must be inverter-based and use a minimum import relay or
				other protective scheme that will ensure that power imported from the utility
				to the network will, during normal utility operations, remain above 1 percent
				of the network's maximum load over the past year, or will remain above a point
				reasonably set by the utility in good faith. At the utility's discretion, the
				requirement for minimum import relays or other protective schemes may be waived
				and alternative screening criteria may be applied.
c. The proposed distributed generation
				facility, in aggregation with other generation on the distribution circuit, may
				not contribute more than 10 percent to the distribution circuit's maximum fault
				current at the point on the primary line nearest the point of
				interconnection.
d. Any proposed
				distributed generation facility, in aggregate with other generation on the
				distribution circuit, shall not cause any electric utility distribution devices
				to be exposed to fault currents exceeding 90 percent of their short-circuit
				interrupting capability. Interconnection of a non-inverter-based distributed
				generation facility may not occur under Level 2 if equipment on the utility's
				distribution circuit is already exposed to fault currents of between 90 and 100
				percent of the utility's equipment short-circuit interrupting capability.
				However, if fault currents exceed 100 percent of the utility's equipment
				short-circuit interrupting capability even without the distributed generation
				being interconnected, the utility shall replace the equipment at its own
				expense, and interconnection may proceed under Level 2.
e. When a customer-generator facility is to
				be connected to 3-phase, 3-wire primary utility distribution lines, a 3-phase
				or single-phase generator shall be connected phase-to-phase.
f. When a customer-generator facility is to
				be connected to 3-phase, 4-wire primary utility distribution lines, a 3-phase
				or single-phase generator shall be connected line-to-neutral and shall be
				grounded.
g. When the proposed
				distributed generation facility is to be interconnected on a single-phase
				shared secondary line, the aggregate generation capacity on the shared
				secondary line, including the proposed distributed generation facility, may not
				exceed 20 kVA.
h. When a proposed
				distributed generation facility is single-phase and is to be interconnected on
				a center tap neutral of a 240-volt service, its addition may not create an
				imbalance between the two sides of the 240-volt service of more than 20 percent
				of the nameplate rating of the service transformer.
i. A distributed generation facility, in
				aggregate with other generation interconnected to the distribution side of a
				substation transformer feeding the circuit where the distributed generation
				facility proposes to interconnect, may not exceed 10 MVA in an area where there
				are transient stability limitations to generating units located in the general
				electrical vicinity, as publicly posted by the Midwest Reliability Organization
				(MRO), the SERC Reliability Corporation (SERC), the Midcontinent Independent
				System Operator, Inc. (MISO) or the Southwest Power Pool (SPP).
j. Except as permitted by additional review
				in subrule 45.9(6), the utility shall not be required to construct any
				facilities on its own system to accommodate the distributed generation
				facility's interconnection.