Two federal circuit court rulings are establishing clearer legal boundaries for state renewable energy programs that restrict credit markets along regional lines, according to a new analysis from the Competitive Enterprise Institute published this week. The analysis examines how courts are applying the Dormant Commerce Clause—a constitutional doctrine that bars states from discriminating against interstate commerce—to renewable portfolio standards (RPS) that require utilities to purchase a specific share of their electricity from renewable sources. The report concludes that states can draw geographic boundaries for renewable credit markets, but only when those lines follow the federal government's own energy market structure rather than state political borders.
The report details how renewable portfolio standards work through Renewable Energy Credits (RECs), which renewable generators earn at a rate of one credit per megawatt hour of electricity produced. These credits represent the separated renewable attributes of generation and can be sold to utility companies, allowing those utilities to claim the electricity came from a renewable source. Some states have begun limiting which credits qualify for compliance, restricting eligibility to generators within defined regions. Confining eligible credits creates scarcity while keeping demand constant, which naturally drives up credit values and provides stronger financial incentives for renewable generators to build and operate within the designated area.
The analysis highlights two circuit court decisions as potential guideposts for future cases. In Allco Finance Ltd. v. Klee, the Second Circuit upheld Connecticut's decision to limit eligible credits to a regional market, rejecting claims from Allco, which owned renewable generators outside the region. The court ruled that the facilities weren't similarly situated to in-region producers because Connecticut's boundary matched the ISO-NE region—an area created by federal authorities to ensure energy reliability—and because credits from outside the region don't directly serve the goal of improving local environmental conditions. By contrast, in Energy Michigan, Inc. v. Michigan Public Service Commission, the Sixth Circuit took a harder line against Michigan's capacity sourcing requirements that created what the court called a "near perfect proxy" to state boundaries, ruling that boundaries in the electricity market may still face strict scrutiny if their application creates disparity along state lines, even without explicit discrimination.
These rulings clarify what states can and can't do when they want to boost local renewable energy development through credit market restrictions. The report explains that the Connecticut statute survived legal challenge because its rationale was backed by the federally designed structure of the energy market, while Michigan's appeal to grid reliability alone wasn't enough to avoid the courts' toughest scrutiny. Laws that discriminate against interstate commerce must meet strict scrutiny, meaning the state has to prove the law advances a legitimate local purpose that can't be adequately served by nondiscriminatory alternatives. When a law regulates evenhandedly and only incidentally burdens interstate commerce, courts apply the Pike test, which upholds the law unless the burden on interstate commerce is clearly excessive compared to the law's local benefits.
The takeaway for state lawmakers is straightforward: they can pursue local renewable energy goals through geographic credit restrictions, but those boundaries must align with the actual structure of federal energy markets rather than state political lines. Appeals to good intentions or grid reliability won't be enough on their own—states need to ground their policies in how electricity markets actually operate.