Illinois Industrial & Data-Centre Environmental Readiness
The Clean and Reliable Grid Affordability Act (PA 104-0458) creates new environmental requirements for data-centre operators effective December 2026.
PA 104-0458 (CRGA) — Enacted Law
Governor Pritzker signed the Clean and Reliable Grid Affordability Act on January 8, 2026, with a general effective date of June 1, 2026. The CRGA imposes new environmental standards on backup generators at data-centre facilities that require a federally enforceable state operating permit or Clean Air Act Title V permit.
Effective December 1, 2026, diesel backup generators at covered data centres must meet standards at least as protective as EPA Tier 4 (40 CFR Part 1039), and natural gas generators must meet EPA Tier 2 (40 CFR Part 1048). Facilities planning new construction or expansion must ensure their generator fleets comply — which may require equipment upgrades, replacement, or revised permit applications.
Who this affects
- Data-centre operators with Title V or state operating permit obligations in Illinois
- Facilities planning new data-centre construction or expansion
- Industrial operators with significant backup-generator capacity
- Companies monitoring large-load interconnection and energy planning requirements
What RSustain provides (PA 104-0458)
- Permit-applicability screeningDetermining whether your facility triggers Title V or state operating permit requirements under the CRGA.
- Backup-generator emissions assessmentEvaluating your existing generator fleet against EPA Tier 4 (diesel) and Tier 2 (natural gas) standards.
- Environmental compliance registersDocumenting all CRGA-relevant obligations, deadlines, and responsible parties in a structured register.
- Air-quality monitoring strategyDesigning monitoring approaches appropriate to your facility and permit requirements.
- Construction-permit implications assessmentEvaluating how CRGA standards affect planned facility construction or expansion timelines.
- Technical coordination with licensed professionalsWhere licensed engineering is required — such as stamped submissions or regulated design work — RSustain coordinates with appropriately licensed professionals.
HB 3673 — Status to Be Verified
Illinois HB 3673 (Climate Corporate Accountability Act) has been proposed to require corporate GHG disclosure for companies with over $1 billion in revenue doing business in Illinois, including Scope 1, 2, and 3 emissions with third-party verification.
As of July 2026, the current legislative status of this bill should be independently verified before assuming compliance obligations. If enacted, RSustain can support applicability review, GHG inventory development, data governance, and pre-assurance gap assessment.
Regulatory status (as of July 2026)
| Regulation | Status | Effective Date | Key Provision |
|---|---|---|---|
| PA 104-0458 (CRGA) | Enacted | Jun 1, 2026 (general); Dec 1, 2026 (generators) | Data-centre backup generator Tier 4/Tier 2 standards |
| HB 3673 | To Be Verified | TBD | Corporate GHG disclosure for >$1B revenue companies |
Regulatory status as of July 2026. Verify HB 3673 status with the Illinois General Assembly.
Frequently asked questions
Does CRGA apply to all data centres in Illinois?
The backup-generator provisions apply to data-centre facilities that require a federally enforceable state operating permit or Clean Air Act Title V permit. Smaller facilities below permit thresholds may not be directly affected, but should confirm their status.
What are EPA Tier 4 and Tier 2 standards?
EPA Tier 4 standards (40 CFR Part 1039) set the most stringent emission limits for non-road diesel engines. EPA Tier 2 standards (40 CFR Part 1048) apply to large spark-ignition (natural gas) engines. Both address particulate matter, NOx, CO, and hydrocarbon emissions.
Can RSustain provide stamped engineering drawings?
RSustain coordinates with appropriately licensed Professional Engineers where stamped submissions or regulated design work is required. Our role is advisory — permit screening, emissions assessment, and compliance register development.