The Chicago school system expects to save $1.3 million a year in utility costs by renovating its main administration building in the city's downtown. The fixes include replacing the massive 43-year-old steam boiler system, which was used to heat several buildings, with a smaller, more efficient unit that will serve only the 20-story administration building. The district also will replace light fixtures and bulbs with higher efficiency models, and put in new windows to stop leaks. A digital building automation system will cut energy costs by making sure lights and heat are turned off on individual floors when no one is using them.