(1)
General interconnection requirements.
(a) The
interconnection of a generating facility with the electrical company's electric
system, the modification of a generating facility that is currently
interconnected to the electrical company's electric system, or the modification
of an existing interconnection must meet all minimum technical specifications
applicable, in their most current approved version, as set forth in WAC
480-108-999.
(b) Interconnection of a generation facility
with a nameplate capacity rating of 300 kW or less must comply with all
applicable requirements in Table 1.
Table 1. 300 kW Capacity or Less.
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Single-Phase
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Three-Phase
|
|
Feature
|
< 50 kW Inverter based
|
< 50 kW Noninverter based
|
< 300 kW Inverter based
|
< 300 kW Noninverter based
|
|
IEEE 1547 compliant
|
X
|
X
|
X
|
X
|
|
UL 1741 listed
|
X
|
X
|
|
Interrupting devices (capable of interrupting
maximum available fault current)
|
X (8)
|
X
|
X (8)
|
X
|
|
Interconnection disconnect device (manual,
lockable, visible, accessible)
|
X (1)
|
X
|
X
|
X
|
|
System protection
|
X (3)(4)(6)
|
X (3)(4)(5)(6)
|
|
Over-voltage trip
|
X (8)
|
X
|
X (8)
|
X
|
|
Under-voltage trip
|
X (8)
|
X
|
X (8)
|
X
|
|
Over/under frequency trip
|
X (8)
|
X
|
X (8)
|
X
|
|
Automatic synchronizing check
|
X
|
X
|
|
Ground over-voltage or over-current trip for
utility system faults
|
X (2)
|
|
Power factor
|
X (7)
|
X (7)
|
|
Notes:
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|
X - Required feature (blank = not required).
|
|
(1) - Electrical company may choose to waive this
requirement.
|
|
(2) - May be required by electrical company;
selection based on grounding system.
|
|
(3) - No single point of failure shall lead to loss
of protection.
|
|
(4) - All protective devices shall fully meet the
requirements of American National Standards Institute C37.90.
|
|
(5) - Electrical company will specify the
transformer connection.
|
|
(6) - It is the customer's responsibility to ensure
that its system is effectively grounded as defined by IEEE Std. 142 at the
point of common coupling.
|
|
(7) - Variance may be allowed based upon specific
requirements per electrical company review. Charges may be incurred for
losses.
|
|
(8) - UL 1741 listed equipment provides required
protection.
|
(c)
Any single or aggregated generating facility with a capacity greater than 50 kW
requires a three-phase interconnection.
(d) The specification and requirements in
this section are intended to mitigate possible adverse impacts caused by the
generating facility on electrical company equipment and personnel and on other
customers of the electrical company. The specifications and requirements in
this section are not intended to address protection of the generating facility
or its internal load, or generating facility personnel. The interconnection
customer is responsible for complying with the requirements of all appropriate
standards, codes, statutes, and authorities to protect its own facilities,
personnel, and loads.
(e) The
specifications and requirements in this section apply generally to the
interconnection to an electrical company's electric system of customer-owned
and operated electric equipment and any other facilities or equipment not owned
by the electrical company to which interconnection agreement(s) apply
throughout the period encompassing the interconnection customer's installation,
testing and commissioning, operation, maintenance, decommissioning and removal
of equipment. The electrical company may verify compliance at any time, with
reasonable notice.
(f) The
electrical company may refuse to establish or maintain interconnection with any
interconnection customer that fails to comply with the requirements in (f)(i),
(ii) and (iii) of this subsection. However, at its sole discretion, the
electrical company may approve alternatives that satisfy the intent of, and/or
may excuse compliance with, any specific elements of these requirements except
local, state and federal building codes.
(i)
Code and standards. All interconnections must conform to all applicable codes
and standards for safe and reliable operation. Among these are the National
Electric Code (NEC); National Electric Safety Code (NESC); the standards of the
Institute of Electrical and Electronics Engineers (IEEE); the standards of the
North American Electric Reliability Corporation (NERC); the standards of the
Western Electricity Coordinating Council (WECC); American National Standards
Institute (ANSI); Underwriters Laboratories (UL) standards; local, state and
federal building codes, and any electrical company's written electric service
requirement approved by the commission. Electrical companies may require
verification that an interconnection customer has obtained all applicable
permit(s) for the equipment installations on its property.
(ii) Safety. All safety and operating
procedures for interconnection facilities must comply with the Occupational
Safety and Health Administration (OSHA) Standard at
29 C.F.R.
1910.269, the NEC, Washington Administrative
Code (WAC) rules, the Washington Industrial Safety and Health Administration
(WISHA) Standard, and equipment manufacturer's safety and operating
manuals.
(iii) Power quality.
Installations must be in compliance with all applicable standards including,
without limitation, IEEE Standard 519 Harmonic Limits, and IEEE Standard 141
Flicker as measured at the PCC.
(2) Specific interconnection requirements.
(a) The electrical company must verify that
the interconnection customer has furnished and installed on its side of the
meter, a UL-approved safety disconnect switch that can fully disconnect the
interconnection customer's generating facility from the electrical company's
electric system. The disconnect switch must be located adjacent to electrical
company meters and shall be of the visible break type in a metal enclosure that
can be secured by a padlock. The disconnect switch must be accessible to
electrical company personnel at all times.
(b) The requirement in (a) of this subsection
may be waived by the electrical company if the interconnection customer:
(i) Provides interconnection facilities that
the interconnection customer can demonstrate, to the satisfaction of electrical
company, perform physical disconnection of the generating equipment supply
internally; and
(ii) Agrees that
its service may be disconnected entirely if generating equipment must be
physically disconnected for any reason.
Such waiver granted by the electrical company to the
interconnection customer must be explicit and in writing.
(c) The electrical company has the
right to disconnect the generating facility at the disconnect switch:
(i) When necessary to maintain safe
electrical operating conditions;
(ii) If the generating facility does not meet
required standards; or
(iii) If the
generating facility at any time adversely affects or endangers any person, the
property of any person, the electrical company's operation of its electric
system or the quality of electrical company's service to other
customers.
(d) Nominal
voltage and phase configuration of interconnection customer's generating
facility must be compatible with the electrical company's system within
generally accepted engineering standards including without limitation IEEE
Standards 141 and 519 at the point of common coupling.
(e) The electrical company must verify on the
basis of evidence provided by the interconnection customer that a generating
facility interconnected to a grid network distribution system or a spot network
distribution system will not impair public safety or quality of service to the
electrical company's other customers as a result of reverse current flow
through the electrical company's network protectors.
(f) All instances of interconnection to spot
network distribution systems require review, studies as necessary, and written
approval by the electrical company.
(g) All instances of interconnection to grid
network distribution systems require review, studies as necessary, and written
approval by the electrical company.
(h) Closed transition transfer switches are
not allowed in network distribution systems.
(3) Specifications applicable to all
inverter-based interconnections. In addition to the requirements contained in
subsections (1) and (2) of this section, the interconnection of any
inverter-based generating facility with the electrical company's electric
system, or the modification of an existing interconnection with an
inverter-based generating facility must meet the following additional technical
specifications, in their most current approved version:
(a) IEEE Standard 1547, Standard for
Interconnecting Distributed Resources with Electric Power Systems;
(b) UL Standard 1741, Inverters, Converters,
and Controllers for Use in Independent Power Systems. Equipment must be UL
listed; and
(c) IEEE Standard 929,
IEEE Recommended Practice for Utility Interface of Photovoltaic (PV)
Systems.
(4) In addition
to the requirements in subsections (2) and (3) of this section, all
noninverter-based interconnections and all inverter-based interconnections
failing to meet the requirements of subsection (3) of this section may require
more detailed electrical company review. The electrical company must
demonstrate the need for additional testing and approval of equipment if the
same equipment has been tested and approved previously for any of the
electrical company's interconnection customers. Electrical companies may
require interconnection customers to pay for needed testing and approval of the
equipment proposed to be installed to ensure compliance with applicable
technical specifications, in their most current approved version, including:
(a) IEEE Standard 1547, Standard for
Interconnecting Distributed Resources with Electric Power Systems, for systems
10 MVA or less; and
(b) ANSI
Standard C37.90, IEEE Standard for Relays and Relay Systems Associated with
Electric Power Apparatus.
(5) The electric company may require
interconnection customers proposing noninverter-based interconnection to submit
a power factor mitigation plan for electrical company review and
approval.
