TL;DR:
A final rule repealing fossil fuel restrictions for new federal buildings and major renovations was published on April 20, 2026, in the Federal Register, effectively removing on-site fossil fuel restrictions from the Clean Energy for New Federal Buildings and Major Renovations (CER) program. At the same time, the Department of Energy extended the compliance stay for the CER provisions to September 1, 2026, providing agencies with additional time to adjust their procurement and design processes. The regulatory framework remains anchored by 10 CFR parts 433 and 435, which govern energy efficiency standards for federal buildings, but the fossil-fuel restriction requirements tied to CER are being rolled back, altering the energy-modeling and fuel-choice landscape for federal projects. For PE exam candidates, this shift underscores the importance of understanding CFR 10 CFR 433 and 435, the CER rule’s history, and how federal actions can influence project design and regulatory context. (federalregister.gov)
Background and Timeline
The CER rule, issued in May 2024, established fossil-fuel generation restrictions for certain new federal buildings and major renovations, mandating that designs reduce on-site fossil fuel consumption and meet stringent energy performance targets. The April 20, 2026 Federal Register final action repeals those fossil-fuel restrictions, signaling a significant policy shift for federal building energy policy. The same Federal Register notice confirms that the compliance date for the associated CER provisions, originally anchored in 10 CFR parts 433 and 435 and tied to the May 1, 2024 rulemaking, is stayed until September 1, 2026. This creates a temporary window during which agencies are not required to implement the fossil-fuel restrictions while remaining subject to other core energy-performance requirements. (federalregister.gov)
The Department of Energy’s Federal Energy Management Program (FEMP) reiterates this stance, stating that as of April 20, 2026, the compliance date for the CER-related provisions is further stayed until September 1, 2026, while DOE reviews the implementation guidance and related interpretation. This aligns with the Federal Register action and provides agencies with time to adapt to the repeal while continuing to work under the broader energy-efficiency framework for federal buildings. (energy.gov)
What Changed in Federal Building Policy
- Repeal of fossil fuel restrictions: The final rule terminates the fossil-fuel consumption restrictions that had been imposed for new federal buildings and major renovations under CER. This reduces regulatory pressure to eliminate on-site fossil fuel use as a design constraint for federal projects. (federalregister.gov)
- Extended stay on CER compliance date: The rule includes a stay of the CER provisions’ compliance deadline until September 1, 2026, providing agencies time to adjust procurement and project planning in light of the repeal. This does not eliminate all energy-efficiency requirements; it changes the fuel-use constraint rather than relaxing ongoing performance expectations. (federalregister.gov)
- Continued CFR framework for federal buildings: The underlying energy performance standards remain codified in 10 CFR parts 433 and 435, which govern how federal buildings are designed and operated with respect to energy efficiency. The repeal affects fossil-fuel limitations, but not the broader structure of performance-based requirements. (law.cornell.edu)
Engineering Implications for Practice
- Fuel selection and system design: With fossil-fuel restrictions repealed, project teams have more flexibility in selecting heating, cooling, and power-generation strategies. However, energy performance remains a priority, so design teams should still apply established efficiency practices, including modeling against baseline standards (for example, ASHRAE 90.1 and IECC when applicable) and pursuing cost-effective electrification where feasible. The policy shift emphasizes performance over fuel source, so benchmarking tools, life cycle cost analyses, and resilience considerations remain essential. The DOE framing around CER indicates continued attention to energy efficiency while removing the specific fossil-fuel constraint. (energy.gov)
- Federal project workflows: Agencies and contractors should anticipate revised procurement language, updated design guides, and potential changes to agency procedures as they align with the repeal. Coordination with facility managers, federal contracting officers, and energy performance contractors will be required to translate the regulatory change into actionable project requirements. (fedcenter.gov)
- Resilience and reliability considerations: The broader energy-efficiency framework still applies, so projects should emphasize reliability, demand flexibility, and integrated design approaches (building envelope performance, high-efficiency HVAC, controls optimization) to maintain or improve energy performance despite fuel-source flexibility. Regulatory updates typically influence how energy modeling is documented and reviewed, reinforcing the need for robust energy-use analysis in design deliverables. (energy.gov)
Implications for PE Exam Candidates
- Core CFR exposure remains important: The regulation highlights the relevance of 10 CFR parts 433 and 435 for federal building energy performance. Even with the repeal of fossil-fuel restrictions, these parts continue to govern design performance criteria for federal projects, so familiarity with their structure and typical compliance pathways is valuable for the PE exam. (law.cornell.edu)
- Regulatory context matters: Understanding how federal policy can shift energy-related requirements helps PE candidates anticipate changes in project constraints, documentation obligations, and the practical interpretation of energy-performance criteria in exam scenarios. The Federal Register and DOE notices provide concrete regulatory anchors for this context. (federalregister.gov)
- Study approach: Include a review of the history and current status of CER, the May 2024 rule, the April 2026 repeal, and the September 2026 stay date. This will help in exam questions that ask about federal building energy policy, compliance timelines, and the interplay between fuel choices and performance standards. Supporting materials include the Federal Register notice (FR Doc. 2026-07628) and DOE summaries of the stay. (federalregister.gov)
Practical Next Steps for Projects and Firms
- Verify applicability on upcoming federal projects: Confirm whether CER fossil-fuel restrictions apply to a given project, and track any agency-specific guidance or amendments to standard contracting language that reflect the repeal and the Sept 2026 stay. (fedcenter.gov)
- Update energy modeling practices: Continue to model to energy-performance targets consistent with CFR 433/435, but plan for fuel-flexible scenarios given the repeal. Ensure documentation clearly demonstrates compliance with the energy-performance criteria in the absence of fossil-fuel restrictions. (law.cornell.edu)
- Monitor regulatory developments: The Federal Register notice and DOE updates indicate that further guidance could follow as agencies implement the repeal. Regular review of the Federal Register and DOE notices will help maintain alignment with current requirements. (federalregister.gov)
Sources
- Repeal of Fossil Fuel Restrictions for New Federal Buildings and Major Renovations of Federal Buildings, Federal Register, April 20, 2026. 91 FR 20868. (federalregister.gov)
- Federal Building Energy Efficiency Rules and Requirements, Department of Energy, June 2026 update on CER stay and CFR references. (energy.gov)
- Justia Regulation Tracker, Regulation: Repeal of Fossil Fuel Restrictions for New Federal Buildings and Major Renovations of Federal Buildings, April 2026. (regulations.justia.com)
- FedCenter Article: Repeal of Fossil Fuel Restrictions for New Federal Buildings and Major Renovations of Federal Buildings, final rule and implications. (fedcenter.gov)
- 10 CFR Parts 433 and 435, Electronic CFR and related summaries, governing energy performance for federal buildings. (law.cornell.edu)
- Federal Register: 91 FR 20868 – Full text and regulatory context, including DATES and SUMMARY sections. (federalregister.gov)