Ohio PUCO Level 1 25kW Solar Interconnection: Procedure Guide for Expedited Review

Key Takeaways

• Ohio's Level 1 interconnection applies to inverter-based solar and storage systems with an export capacity of 25 kilowatts or less.
• The Electric Distribution Utility (EDU) must complete its review within 21 calendar days for standard projects (August 2026).
• The maximum application fee for Level 1 interconnection is fifty dollars (August 2026).
• Projects failing Level 1 screens have 14 calendar days to resubmit under Level 2/3 to retain their queue position.

What is the Ohio PUCO Level 1 25kW Solar Interconnection Procedure?

The Public Utilities Commission of Ohio (PUCO) established the Level 1 review procedure under Ohio Administrative Code Rule 4901:1-22-06. This procedure provides an expedited pathway for inverter-based solar and storage systems to connect to the grid. It applies to distributed energy resources (DER) with an export capacity of twenty-five kilowatts or less (August 2026). This streamlined process includes specific technical screening criteria and timelines for Electric Distribution Utilities (EDUs).

What are the technical requirements for Ohio Level 1 interconnection?

Ohio's Level 1 interconnection procedure specifies several technical requirements to ensure grid stability and safety. These criteria are outlined in Ohio Administrative Code Rule 4901:1-22-06.

The DER must use inverter-based equipment certified in compliance with the IEEE and UL standards set forth in Ohio Administrative Code Rule 4901:1-22-03 (August 2026).

For interconnection to a radial distribution circuit, the aggregated generation, including the proposed DER, on the circuit shall not exceed one hundred per cent of the line section's Relevant Minimum Load (August 2026). This load is measured at the substation or calculated for the line section.

The proposed DER, in aggregation with other generation on the distribution circuit, shall not contribute more than ten per cent to the distribution circuit's maximum fault current (August 2026). This is measured at the point on the high voltage (primary) level nearest the proposed point of common coupling.

For spot networks, aggregated inverter-based generation, including the proposed DER, shall not exceed the smaller of five percent of a spot network's maximum load or fifty kilowatts (August 2026).

Direct current injection must be maintained at or below five-tenths of a percent of full rated inverter output current into the point of common coupling (August 2026).

What is the application process and timeline for Ohio Level 1?

The Level 1 interconnection process is designed for efficiency. After the Electric Distribution Utility (EDU) notifies the applicant that it has received a complete short form interconnection service application, the EDU performs a review. This review must be completed within twenty-one calendar days (August 2026). For hybrid facilities, the review period extends to thirty calendar days (August 2026).

If the application is approved, the EDU will provide the applicant a standard interconnection agreement within ten calendar days after the determination (August 2026). The EDU's tariff for a Level 1 fee shall not exceed fifty dollars (August 2026), and this fee may be waived.

How do we verify these Ohio interconnection rules?

We verify these details by directly consulting the official source. All information regarding Ohio's Level 1 interconnection procedure, including technical limits, review timelines, and fee caps, is drawn from Ohio Administrative Code Rule 4901:1-22-06. We accessed this document on August 23, 2026, via the official Ohio codes website. This direct consultation ensures the accuracy and currency of the regulatory information presented.

When might an Ohio solar project not qualify for Level 1 review?

The Level 1 review procedure is specifically for inverter-based systems with an export capacity of 25 kilowatts or less (August 2026). If your project exceeds this capacity, it will not qualify for Level 1 and must pursue a Level 2 or Level 3 review.

Additionally, a project might not qualify if it fails any of the technical screening criteria, such as exceeding the 100 percent Relevant Minimum Load limit on a radial circuit or contributing more than ten per cent to the distribution circuit's maximum fault current (August 2026).

If a project fails Level 1 screens, the applicant has fourteen calendar days to submit a new application under Level 2 or Level 3 procedures (August 2026). Submitting within this timeframe allows the project to retain the queue position assigned to the original Level 1 application. Understanding these limitations early can help you plan your project's interconnection strategy.

Where can I find more information on US solar interconnection?

Navigating state-specific interconnection rules is crucial for solar project development. For a broader understanding of distributed generation regulations in Ohio, you can consult our Ohio PUCO Rule 4901:1-22 Distributed Generation Interconnection Guide.

Other states also have specific guidelines. For comparison, you might review our guides on Florida PSC Tier 1, 2, and 3 Solar Interconnection and Insurance Rules or the Texas PUC Rule 25.211 Distributed Generation Interconnection Guide. These resources can help you understand the varying regulatory landscapes across the United States. If you are planning a system, you can use a solar sizing tool to estimate your needs before engaging with interconnection procedures.