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Quick Fact: Decatur Island Solar Expansion August 2026 Update

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Avoiding Tier 2

OPALCO’s mission has not changed: safe, reliable, affordable electricity for San Juan County. What has changed is how hard that mission is getting to deliver. OPALCO’s low-cost power comes from a capped allocation of BPA Tier 1 hydropower. Once system load exceeds that allocation, additional kilowatt-hour purchases come from Tier 2 or market-rate power — at significantly higher cost, borne by every member through rates.

The County is growing, and OPALCO is obligated to serve every approved connection regardless of where or when development happens. San Juan County issues new building permits every year, and electricity usage is projected to grow approximately 30% over the next 20 years — a trend expected to continue as electrification (EVs, heat pumps, water heaters) accelerates.

OPALCO has historically managed this growth from the demand side: conservation, efficiency, rooftop solar, battery storage, and Switch It Up financing. These tools have kept OPALCO under its Tier 1 allocation but there is now a real need to add utility scale generation to keep us within our allocation.

Utility Scale Solar Projects

In recent years, OPALCO has begun to purchase the more expensive Tier 2 power from BPA to cover our needed electricity. Bringing Decatur’s expansion online — and, eventually, Bailer Hill — is the direct way to stop those Tier 2 purchases from growing and keeping costs lower for the long-term benefit of the community. Additionally, Tier 2 power comes from carbon-based resources which add to the cost and move away from key sustainability goals.

The existing Decatur Island Community Solar project (2018) is OPALCO’s proof of concept: 504 kW DC, a 1 MW / 2.6 MWh battery, roughly 570,000 kWh generated annually. It was financed by member subscriptions and grants. The ~270 member-investors have fully recovered their investment, and a portion of the project goes towards OPALCO’s energy assistance program helping low-income members.

The Cost of Delays

OPALCO’s two recent utility-scale solar projects have both been delayed. Bailer Hill has been on hold pending further study per the Department of Ecology. Decatur’s expansion only cleared its Conditional Use Permit in May 2026, after a contested review, and OPALCO is now working through the permit’s remaining conditions. This local generation is what OPALCO is counting on to stay inside its Tier 1 allocation but permitting delays continue to push this timeline back.

Independent Cooperative Finance Corporation benchmarking puts OPALCO’s 2025 total cost of electric service per member at $2,259 — below the Washington co-op median, the national median, and the median for co-ops OPALCO’s size. OPALCO’s five-year cost growth (about 15%) has also run well behind state and national co-op medians (21–29%). The reason we need utility scale projects today is that the power supply cushion behind those good numbers is thinning. With the BPA hydropower contract renewal in 2028 there is no new Tier 1 hydropower available so at that point rates will continue to go up.

Decatur Island Solar Expansion Project

Why locate solar on Decatur? The Decatur Island Expansion parcel is designated Rural General Use which allows for solar (renewable) generation. Most land in San Juan County does not allow for renewable generation projects as SJC permitting of utility scale electricity generation is still based on old, dirty, loud and noisy diesel generating facilities.

The proposed site parcel is adjacent to an OPALCO substation and OPALCO’s existing solar and battery project. It is also next to a San Juan County Public Works maintenance and storage yard. The storage yard (including delineated Natural Growth Area) has historically been used for derelict vehicle storage (OPALCO removed over 14 derelict vehicles from the site since purchasing in 2025). The forest has been previously logged. The map below shows what is on and around the site today.

Decatur Solar Expansion parcel: existing substation, existing solar, county public works yard, storage yard, previously logged area, and adjoining private residential parcel.

The Decatur Island Solar Expansion is one part of a broader, necessary strategy to protect power affordability, manage growth responsibly, and strengthen the resilience the community OPALCO serves. The project reflects more than a year of community engagement, environmental studies for permitting, and project changes made in response to input from local community and data collected.

Completing the Decatur Solar Expansion project will allow OPALCO to drop below buying expensive Tier 2 power that OPALCO purchases from BPA, avoid purchasing carbon based electricity and partially offsets electricity load growth specific to Decatur Island.

Previously, the OPALCO Board approved the purchase of 6,400 solar panels for $2.4M that are staged on San Juan and awaiting installation in the islands (as pictured).

Background Info on Work Done on Project To Date

Community Engagement:

Conditional Use Hearing

On Tuesday, May 12, OPALCO was notified that they were granted the Conditional Use Permit for the Decatur Island Solar Expansion Project. The Decatur Island Solar Expansion project is a proposed ~1.6 MW AC Community Solar project. It’s adjacent to OPALCO’s substation and the current Community Solar project that was installed in 2017.

OPALCO has undergone extensive environmental review and project planning to include a site plan, critical area and wetland delineation, National Environmental Policy Act, State Environmental Policy Act, a stormwater plan, Cultural Resources Assessment, clearing and grading checklist, land use checklist, and a native landscaping plan. In February 2026, OPALCO presented the prepared material to the San Juan County Hearing Examiner in order to proceed with the permitting requirements and conditions.

There were two appeals to the State Environmental Policy Act (SEPA) determination of non-significance (DNS). OPALCO prepared a detailed and prescribed SEPA checklist and San Juan County staff gave the checklist a DNS, which means there is nominal environmental impact. Both appeals to the DNS ruling were denied by the Hearing Examiner.

Decatur residents have brought forward concerns about this project during various community engagement meetings. OPALCO has made efforts to meet community requests when possible. There are no legal reasons the project cannot move forward as all requirements were found to be met by the Hearing Examiner. OPALCO hopes to continue to work with the community as the project proceeds.

Decatur Load Growth Rationale

The Decatur Solar project will help address the approximately 30% projected load growth on Decatur Island, reducing reliance on mainland power imports. Developing local renewable generation improves energy resilience, reduces dependence on transmission from the mainland, and positions OPALCO to better manage future load growth across the island system.

As regional energy supply challenges continue to grow, projects like Decatur Solar Expansion present an important step toward responsibly developing local energy resources while maintaining the cooperative’s commitment to thoughtful planning and community engagement.

Project Evolution

As the Decatur Solar project has moved forward, OPALCO has worked closely with San Juan County and the Decatur community to reduce impacts and incorporate local feedback. The project has evolved significantly from the original concept.

The original concept considered maximized the ~23 acres (plus 3 acres on San Juan County parcel) for solar development to account for environmental constraints. The current proposal has been significantly scaled back to approximately 8.5 acres, with the County parcel removed from the project entirely. This redesign represents a meaningful effort to respond to community concerns while maintaining the project’s core purpose of providing local renewable energy.

Environmental Protections

The project has undergone comprehensive environmental review through the San Juan County Conditional Use Permit process, as well as SEPA and NEPA environmental review. Studies and plans include a Critical Areas and Wetland Delineation Report, a Stormwater Management Plan addressing site drainage and runoff, a Cultural Resources Assessment, a Landscaping Plan to buffer the project and improve visual integration and fire mitigation planning in coordination with local fire response needs. These studies ensure the project is designed to meet applicable environmental protections and regulatory requirements.

Community Benefits for Decatur Island

OPALCO is dedicated to protecting the local environment, responding to community concerns, and coverage of future load growth. OPALCO held several community meetings with the Decatur Island community and incorporated feedback into the project planning. In response to feedback from the Decatur community, OPALCO has incorporated several improvements that directly benefit the island. Including:

Fire Mitigation Plan

Based on the selected equipment, applicable safety certifications, proposed installation standards, commissioning procedures, and long-term maintenance practices, the fire risk associated with the Decatur Solar Expansion is considered low and consistent with accepted industry experience for modern utility-scale photovoltaic facilities.

The combination of certified photovoltaic equipment, code-compliant electrical design, rigorous quality assurance, ongoing maintenance, and active vegetation management provides multiple independent layers of protection intended to minimize both electrical ignition hazards and wildfire risk throughout the operational life of the project.

Industry experience has shown that fires associated with photovoltaic facilities are uncommon. When they do occur, investigations have generally determined that they are associated with installation deficiencies or failures of balance-of-system electrical equipment—such as conductors, connectors, inverters, disconnect switches, or transformers—rather than failures of the photovoltaic modules themselves. For this reason, proper engineering, quality construction, equipment certification, commissioning, and long-term maintenance are the primary means of reducing fire risk.

The Decatur Island Community Solar Expansion Project incorporates multiple independent layers of fire prevention, including:

  • Photovoltaic modules certified to nationally recognized safety standards.
  • Electrical equipment listed and labeled by Nationally Recognized Testing Laboratories (NRTL).
  • Electrical design compliant with the National Electrical Code and applicable Washington State requirements.
  • Utility-grade protective relaying.
  • Ground-fault and overcurrent protection.
  • Continuous monitoring through OPALCO’s Supervisory Control and Data Acquisition (SCADA) system.
  • Remote shutdown capability.
  • Comprehensive commissioning and acceptance testing.
  • Routine inspection and preventive maintenance.
  • Infrared thermographic inspection of energized electrical equipment.
  • Active vegetation management.
  • Maintained emergency access and defensible space around critical equipment.

The project will remain under continuous inspection and maintenance throughout its operational life. Routine vegetation management, periodic inspection of electrical equipment, preventive maintenance, and continuous monitoring substantially reduce the likelihood of equipment failures while improving emergency access for utility personnel and responding fire agencies.

APRIL 2026 – OPALCO Project Approval

The Board of Directors dedicated two meetings to the Decatur Island expansion. They reviewed the various materials and directed staff to move forward on the project with specifications.

Board Materials for April:

Environmental and Permitting Reports:

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