Ascent Solar Technologies Inc., the Littleton, Colo.-based developer of thin film photovoltaic (PV) materials, announced that the U.S. Air Force Research Laboratory (AFRL) has contracted to increase funding of Ascent Solar's development of high-performance thin film tandem PV cells based on its flexible monolithically integrated copper indium gallium selenide (CIGS) technology. The contract modification represents up to $749,000 of additional contract value over a 27-month period.
Since 1995, AFRL has provided funding for the development of the flexible CIGS at ITN Energy Systems Inc. and now at Ascent Solar, including the development of aspects of future tandem devices. Tandem solar cells are two solar cells in a stack, where the top cell collects the blue portion of the solar spectrum and the bottom cell collects the rest of the visible spectrum. According to Ascent Solar, it is believed that the type of technology pursued by this AFRL program has the potential to reach an efficiency of 20% in the future.
‘While our baseline CIGS that utilizes a single junction to convert the sun's energy has been performing very well, we are always striving to increase cell performance that can potentially lead to further reductions in system-level costs to the end user,’ says Dr. Joseph Armstrong, Ascent Solar's chief technical officer.