Domestic Content Verification

Supply chain diligence for solar and storage tax credit claims

The Section 48E Investment Tax Credit (ITC) and Section 45Y Production Tax Credit (PTC) Domestic Content Bonus can improve project economics, but lenders and tax credit counterparties need more than a supplier statement. They need a clear, documented basis for the domestic content position.

Intertek CEA supports project owners, sponsors, and financing parties with domestic content verification support for U.S. solar and storage projects. Our work helps confirm whether supplier documentation, component origin claims, and project assumptions align with the selected domestic content claim.

Why it matters

Domestic content compliance is complex, documentation-heavy, and increasingly important to project finance. A weak file can create risk during lender diligence, tax credit transferability review, or future audit.

Key risks include:

• Incomplete supplier documentation

• Unsupported domestic production claims

• Direct cost data gaps

• Unclear Manufactured Product Component treatment

• Steel and iron documentation issues

• Changes between N-23-38  and N-26-15 guidance

• Mismatch between procurement assumptions and tax credit strategy

Two pathways, different diligence needs

• Safe Harbor Method
  Uses Treasury-defined component values. Simpler to apply, but less flexible and highly dependent on whether documented domestic components are available for the project configuration.

• Direct Cost Method
  Uses actual supplier cost data. More flexible, but requires deeper supplier transparency, direct cost support, and careful documentation of domestic versus imported Manufactured Product Components.

What Intertek CEA reviews

• Project equipment list and domestic content strategy

• Module, tracker, racking, inverter, and BESS supplier documentation

• Bill of materials and Manufactured Product Component evidence

• Direct cost information, where applicable

• Domestic production attestations

• Steel and iron documentation

• Supplier claims against applicable guidance

• Documentation gaps and audit exposure

Scope of Support

1. Domestic content pathway review

Assess the project’s selected approach, applicable guidance, equipment scope, and key assumptions.

2. Supplier documentation review

Review supplier materials for completeness, consistency, and support for domestic production claims.

3. Component mapping

Map relevant equipment to Manufactured Products, Manufactured Product Components, and steel/iron categories.

4. Gap and risk assessment

Identify missing documents, unsupported claims, inconsistent assumptions, and diligence questions likely to arise.

5. Supplier follow-up support

Prepare targeted documentation requests for suppliers when additional evidence is needed.

6. Audit-ready package

Organize findings, source documents, assumptions, and open items into a clear review package for financing and audit support.

What clients gain

• Clearer lender diligence
  A concise, organized basis for the domestic content position.

• Stronger supplier file
  Better visibility into which claims are supported and which need follow-up.

• Reduced audit scramble
  Documentation, assumptions, and gaps are identified before they become transaction issues.

• Commercially grounded review
  Support informed by solar, storage, supplier, and procurement market experience.