eDataFeed is a Web service that allows subscribers to select and “stream” PJM Locational Marginal Price (LMP) data, plus some operational data directly into their system. eDataFeed delivers information in a format called Simple Object Access Protocol (SOAP) that enables data capture, analysis and decision support to meet the trading, risk management and business decisions of PJM’s members (customers). PJM serves as an independent information clearinghouse as it coordinates the buying, selling and trading of electric energy and energy-related products among its member companies participating in the PJM markets. 

WSDL (requires authentication) | Register

eDataFeed Release 5.0 is now available for production access at https://edatafeed5.pjm.com/edatafeed for registered users.

New features include: Support for compression of result sets during transfer, WS-Security, Microsoft .Net client and 72-hour Load Forecast data. 

eDataFeed Release 5.0 Documentation (DOC) 
eDataFeed 5.0 FAQ (DOC) 
eDataFeed Example Client 5.0 (.Net) (ZIP) 
eDataFeed Example Client 5.0 (Java) (ZIP)