Washington State Net Metering And Rcw 80 60 Guide

Key Takeaways

• Washington State's net metering framework is primarily established under Revised Code of Washington (RCW) Chapter 80.60.
• Residential solar and energy storage installations may be eligible for a 30% federal income tax credit under Section 25D.
• Grid-tied inverters must meet specific safety standards, including UL 1741-SB and IEEE 1547-2018 anti-islanding parameters.
• Operating a generating facility before receiving written Permission to Operate from the utility is strictly prohibited.

Understanding Washington State's Net Metering Framework

Net metering in Washington State is governed by the Revised Code of Washington (RCW) Chapter 80.60. This framework allows customers of electric utilities such as Puget Sound Energy (PSE), Avista Utilities, Seattle City Light, and Snohomish PUD to receive credit for excess electricity generated by their solar systems and sent back to the grid. The billing regime is based on 1:1 retail net metering, with an annual true-up date of 30 April.

Federal Tax Credits and Sales Tax Exemptions for Solar in Washington

Installing solar and energy storage systems in Washington State can offer financial benefits beyond net metering. Residential clean energy expenditures are eligible for a federal income tax credit.

Residential solar installations claim a 30% credit against total federal tax liability under Section 25D. This credit also extends to qualified energy storage property. To be eligible, energy storage property must have a capacity of 3 kilowatt-hours or greater. Expenditures for solar and residential storage qualify for a 30% credit under Section 25D of the IRC.

Safety and Interconnection Requirements for Solar Installations

Connecting a solar generating facility to the grid in Washington State involves specific safety and technical requirements to ensure grid stability and public safety. These requirements are critical for compliance and safe operation.

Grid-tied solar inverters must comply with UL 1741-SB and IEEE 1547-2018 anti-islanding parameters. These standards ensure that inverters safely disconnect from the grid during power outages, protecting utility workers.

A lockable utility-accessible AC disconnect switch is required within 10 feet of the revenue meter. This switch provides a safe means for utility personnel to disconnect the solar system from the grid.

Electrical safety rules, such as those under WAC -46B, apply to installations. Rooftop PV systems must incorporate rapid shutdown devices complying with NEC 690.12 specifications. This allows emergency responders to quickly de-energise the solar array.

Connection of generating sources to panelboards must follow the 120% ampacity calculation in NEC 705.12. Dedicated overcurrent protection devices must be sized according to NEC 705.12 120% busbar rules. Equipment grounding conductors must be bonded directly to the main building service grounding electrode. Photovoltaic systems operating at 80 volts DC or greater require certified Type 1 AFCI protection.

It is strictly prohibited to operate the generating facility prior to receiving written Permission to Operate from the utility.

What you can check yourself, and what you cannot

As a homeowner, you can verify that your installer has provided documentation confirming compliance with the mentioned standards, such as UL 1741-SB for your inverter or NEC 690.12 for rapid shutdown devices. You can also visually confirm the presence of a lockable AC disconnect switch near your meter.

However, detailed electrical inspections, sizing calculations for overcurrent protection, and verification of grounding conductor bonding are tasks for accredited installers and licensed electricians. Changing inverter settings or attempting to connect your system to the grid before utility approval can lead to safety hazards and breach your connection agreement. Always consult with your installer or utility for specific technical details and operational permissions.

What the published sources do not tell you

While the Revised Code of Washington (RCW) Chapter 80.60 establishes the general net metering framework, specific details such as the cumulative net metering cap status can vary by local utility. In Washington PUD territories, it is necessary to confirm the local utility cumulative net metering cap status under RCW 80.60.020. The provided federal tax credit information is general; individual tax situations may vary, and consultation with a tax professional is recommended. published guidance does not detail specific utility interconnection processes or forms, which are typically found on individual utility websites.