Today, April 30, 2024, the U.S. Department of Energy (DOE) revised its National Environmental Policy Act (NEPA) implementing procedures to revise categorical exclusions for upgrading and rebuilding powerlines and for solar photovoltaic systems. Under the new rulemaking, environmental reviews will not automatically be required for projects related to solar installations. The rulemaking also adds a categorical exclusion for certain energy storage systems and adds flexibility for power grid powerline relocation.

A categorical exemption (“CX”) is applicable where a federal agency, including the DOE, has concluded that a proposed project or action does not have a significant effect on the human environment and for which neither an environmental assessment (EA) nor an environmental impact statement (EIS) is required.[1] Once a CX is promulgated through notice and comment rulemaking, it is added to an Appendix that includes the relevant requirements for the specific CX and other requirements applicable to all CXs.

One of the primary changes made by the rulemaking is the removal of a land area limitation currently in place for solar projects. The current CX for solar projects excludes the installation, modification, operation, and removal of solar photovoltaic (PV) systems, but only if the project is located within a previously disturbed or developed area comprising less than 10 acres.[2] However, the new rule removes this 10-acre limit, making the exclusion available to larger projects.

DOE regulations also require that projects comply with additional requirements, known as “integral elements,” in order to be eligible for a CX. These conditions apply to any CX, including the CX for solar projects. Under these additional requirements, projects must not:

  • threaten a violation of applicable environment, safety, and health requirements;
  • require siting and construction or major expansion of waste storage, disposal, recovery, or treatment facilities;
  • disturb hazardous substances, pollutants, or contaminants that preexist in the environment such that there would be uncontrolled or unpermitted releases;
  • have the potential to cause significant impacts on environmentally sensitive resources [1]; or
  • involve governmentally designated noxious weeds or invasive species, unless certain conditions are met.[3]

DOE received comments to the proposed rule raising concerns about impacts of solar projects on wildlife and habitat. In response to those concerns, DOE added a condition that a proposed project must be “consistent with applicable plans for the management of wildlife and habitat, including plans to maintain habitat connectivity” in order to qualify for a CX.

The final rule will go into effect on May 30. The full version of the final rule can be viewed here.

[1] See 40 C.F.R. § 1508.1(d).

[2] 10 C.F.R. Part 1021, Appx. B, at § B5.16, available at

[3] 10 C.F.R. Part 1021, Appx. B.