Southern Co. operates 76 power plants with more than 12,000 craft workers, many of them contractors, rotating among different plants as needed. Until recently, it kept records on worker certifications, training, drug tests, background checks and other information at each plant. When a worker switched plants, it was often easier to redo tests and training rather than chase down information at another plant. But that approach was costly and annoyed workers. Last year, Southern centralized all the worker information with a Web application that provides a central repository of worker data. Now, workers can easily move from plant to plant, using technology like hand scanners to gain entry. The system will save the company $5.8 million over 4.5 years in labor and drug-testing costs. It's also being sold to other utilities.