Amici curiae are leading economists and experts in the field of the markets for electric power. Amici also serve as professors and teachers of economics; write on economic issues; advise clients on the economic impact of legislation, regulations, and other policies; or previously were employed by an independent system operator (“ISO”). A summary of the qualifications and affiliations of amici is provided as an appendix to this brief. Amici file this brief as individuals and not on behalf of the institutions with which they are affiliated. None of amici are being compensated in connection with this brief.1 All parties in these consolidated appeals have consented to the filing of this brief. See Fed. R. App. P. 29(a)(2).

Although amici do not always agree on economic issues presented by energy- market regulations, amici share the concern that the Illinois’s Zero Emissions Credit (“ZEC”) program at issue in this case will have a deleterious effect on the federally regulated wholesale energy and capacity markets. Amici have dedicated substantial professional effort to helping to promote the efficient operation of wholesale electric markets, sharing a belief that efficient, competitive markets promote the efficient supply of electric power for the benefit of the public. This brief is intended to explain a number of relevant issues in this case: (1) how the district court misunderstood the functioning of ISO and regional transmission organization (“RTO”) markets by finding that the ZEC program is tied to energy production and not energy sales; (2) how this particular subsidy will distort the Federal Energy Regulatory Commission (“FERC”)-approved capacity and energy auctions and influence entry and exit decisions of other generators; and (3) why this subsidy may not fulfill the stated purpose of reducing greenhouse gas emissions.