The U.S. Energy Dept. is seeking an additional $9 billion in loan-guarantee authority from Congress for nuclear powerplants so it could approve before Sept. 30 three leading applications that have been submitted by large utilities, according to an agency spokeswoman. If granted, the extra funds would boost DOE’s loan-guarantee authority to $19.2 billion. Agency Secretary Steven Chu would not identify specific beneficiaries. Industry officials say the leading contenders are NRG and Toshiba’s south Texas project, UniStar’s Calvert Cliffs project in Maryland and the South Carolina Electric & Gas Summer project.