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Clark Public Utilities

Washington Utility Interconnection & net metering rules
Net Metering Allowed1
NEM TypeAnnual
Line Taps Allowed0
Load Taps Allowed0
AC Disconnect RequiredSituational

Net metering & export

Net Metering Allowed
1
NEM Type
Annual
TOU Utility
0
Post Solar Billing Method
Net Metering
Net Excess Generation Notes

If the electricity generated by the Customer during the billing period, or any portion thereof, exceeds the electricity supplied by the Utility, then the Customer shall be credited for the net excess kilowatt-hours generated during the billing period. On April 30 of each calendar year, any remaining unused kilowatt-hour credit accumulated by the Customer during the previous year (May 1 through April 30) shall be granted to the Utility, without any compensation to the Customer.

Rebates Offered
0

Interconnection & taps

Approval Req To Install
Yes
Interconnection Level
3
Line Taps Allowed
0
Load Taps Allowed
0
Automatic Transformer Upgrade Size
0
Meter Aggregation Allowed
1

System size & offset

System Size Restrictions
25
System Size Restriction Type
AC kW
System Size Battery Included
0
System Size Includes Existing Systems
0
Offset Type
Combination
Offset Value
100
Offset Calculation Basis
Historical
Offset Calculation Period
12
Industry Standard Watts Sqft
2
Offset Calc Tool
Historical Usage

Metering & disconnect

Production Meter Required
Yes
Production Meter Position
Inv-Disco-PM-POI
Production Meter Labeling
Production Meter
AC Disconnect Required
Situational
AC Disconnect Criteria

An AC disconnect switch is not required when the generating facility meets the following conditions:

  • Has a capacity of 25 kW or less;
  • Is an inverter-based UL 1741 certified system;
  • Is interconnected through a self-contained socket-based meter of 320 amps or less.

An AC disconnect switch is not required by WA Labor & Industries

AC Disconnect Labeling
Visible Lockable Labeled Disconnect
Allowed Meter Adapter
None

Plans & docs

Site Plan Reqs

Standard - must show proposed PM socket location.

SLD Reqs

Production meter must be ringed.

Electric Service Reqs
  • Must be inverter based and the inverter must meet the UL 1741 and IEEE 1547 requirements.
  • Single phase and the nameplate rating must be at 25kW AC or less.
  • Cannot require construction of new or upgrade existing utility facilities, other than meter changes.
  • If connected to a 240V service, the addition must not create an imbalance of the two sides of the 240V service of more than 5kVA
Placards

Common labeling is required. Must be in accordance with NEC requirements.

  • Must be posted on meter base, disconnects and transformers informing utility personnel that a generating facility is located on the premise.
Electrical Stamp Required
0
Equipment Approvals
California Energy Commission
Meter Num Req SLD 3LD
0
ESID Num Req SLD 3LD
0
Website
link
Phone
(360) 992-3244

Other details

Restrict Inspection
0
Address ID
3836423
Express Planset Eligible
No
Compiled from public records, 2026. Tariffs and interconnection rules change; verify with Clark Public Utilities before you rely on this. The useful move: if an installer says you need a main panel upgrade, ask how these tap and interconnection policies were considered first.