The Department of Energy (DOE) issued a draft National Transmission Needs Study and opened a 60-day public comment period. The study is a comprehensive assessment of electric transmission constraints and capacity needs across the United States, examining where the existing transmission grid is insufficient to meet current and projected electricity demand reliably and at reasonable cost.

Comments are due 60 days after publication.

The National Transmission Needs Study is not merely an academic exercise. It has direct legal and regulatory consequences through its potential to inform National Interest Electric Transmission Corridor (NIETC) designations.

Under the Federal Power Act (as amended by the Energy Policy Act of 2005 and the Inflation Reduction Act of 2022), the DOE has authority to designate geographic areas as National Interest Electric Transmission Corridors if it finds that the area is experiencing or is expected to experience electric energy transmission capacity constraints or congestion that adversely affects consumers.

A NIETC designation has significant consequences:

• It triggers the Federal Energy Regulatory Commission's (FERC) backstop transmission siting authority under FPA section 216, allowing FERC to issue permits for transmission facilities in the corridor even if a state has denied or failed to act on a permit application
• It may facilitate access to federal financing and loan guarantees for transmission projects in the corridor
• It can affect the permitting timeline and risk profile for transmission projects in the designated area

The Inflation Reduction Act of 2022 significantly expanded DOE's NIETC designation authority and FERC's backstop siting authority. The 2026 Transmission Needs Study is the first major study issued under the expanded framework, making it particularly significant for understanding how DOE intends to use its enhanced authorities.

The draft study assesses transmission needs across several dimensions:

Geographic Constraints The study identifies specific regions where transmission constraints are limiting the ability to move power from generation sources to load centers. This includes constraints on interregional transmission — the ability to move power between different regional grid operators — which has become increasingly important as renewable energy development concentrates in areas with high wind and solar resources that may be distant from population centers.

Reliability Needs The study examines where transmission constraints create reliability risks — situations where the grid may be unable to meet demand during peak periods or following the loss of a major transmission element.

Economic Congestion The study identifies areas where transmission congestion is causing significant economic costs — forcing the dispatch of more expensive generation resources because cheaper resources cannot deliver power to where it is needed due to transmission constraints.

Clean Energy Integration The study examines the transmission infrastructure needed to integrate large amounts of new renewable generation, including offshore wind, onshore wind, and utility-scale solar, into the grid.

Corridor Designation Risk and Opportunity Areas identified in the study as having significant transmission needs are candidates for NIETC designation. For transmission developers and infrastructure investors, a NIETC designation can reduce permitting risk by providing a federal backstop if state permitting processes stall. For landowners and local governments in potential corridor areas, a NIETC designation raises concerns about federal preemption of state siting authority.

Grid-Interconnection Strategy The study's identification of constrained areas informs grid-interconnection strategy for generation developers. Projects in areas with significant transmission constraints face longer interconnection queues, higher interconnection costs, and greater uncertainty about whether they will be able to deliver power to market. The study's findings may affect project siting decisions and the economics of proposed generation projects.

Project Finance Transmission projects in NIETC-designated corridors may have access to DOE loan guarantees and other federal financing support, which can improve project economics and reduce financing risk. Project-finance counsel should monitor the study's findings and any resulting NIETC designations for their implications on financing structures.

Land Use and Siting NIETC designations and the transmission projects they facilitate have significant land-use implications — rights-of-way, easements, eminent domain proceedings, and impacts on adjacent properties. Real estate owners, developers, and local governments in areas identified in the study should track the comment period and any resulting designations closely.

Procurement Opportunities Large-scale transmission projects generate significant procurement opportunities for EPC contractors, equipment suppliers, and engineering firms. The study's identification of needed transmission infrastructure provides advance notice of where major projects are likely to be developed.

The 60-day comment period provides an opportunity for stakeholders — utilities, transmission developers, renewable energy developers, state regulators, local governments, landowners, and consumer advocates — to submit comments on the study's findings, methodology, and conclusions.

Comments that identify errors in the study's assessment of specific regional constraints, or that provide additional data on transmission needs or constraints, can influence the study's final conclusions and, ultimately, DOE's NIETC designation decisions.

The DOE's draft 2026 National Transmission Needs Study is a foundational document for understanding where the U.S. electric grid faces its most significant constraints and where federal transmission authorities are most likely to be deployed. Energy developers, utilities, infrastructure investors, and project-finance counsel should engage with the comment period and monitor the study's finalization and any resulting NIETC designations as a core element of their grid-interconnection and project-development strategy.