Three Illinois nuclear power plants—Byron, Dresden, and Quad Cities—did not clear in last week’s long-delayed PJM Interconnection capacity auction, Exelon Generation reported in a filing with the Securities and Exchange Commission.

The news is likely to further pressure the Illinois General Assembly to pass a comprehensive energy package—one with subsidies for the state’s financially ailing nuclear plants—before Exelon moves forward with its plan, announced last August, to prematurely retire Byron and Dresden.