OAK RIDGE, Tenn., Dec. 21 -- A solar energy system being developed at the Department of Energy's Oak Ridge National Laboratory (ORNL) may hold the key to a three-fold improvement over conventional photovoltaic cells. The new technology, called a full-spectrum solar energy system, is designed to use sunlight's energy more efficiently. Instead of inefficiently converting the visible light found in sunlight into electricity only to reconvert a sizeable portion back into interior light, it makes more sense to just collect and distribute the light directly, explained Jeff Muhs, a researcher in ORNL's Engineering Technology Division. By using the visible portion of the light spectrum, we can reduce the amount of electricity we consume for lighting commercial buildings, Muhs said. We can use the other portions of the spectrum to generate electricity. The system that ORNL and its industry partners are developing uses roof-mounted two-axis tracking concentrators that separate the visible and infrared portions of the sun's rays. The system uses large-diameter optical fibers to distribute visible light to interiors of buildings, and converts infrared portions of the solar spectrum into electricity.