Low-concentration facade integrated photovoltaic systems (LFP) made from transparent acrylic CPC segments having their absorbers in the form of solar cells may play an effective role in reducing cooling loads inside buildings. The performance of CPC segments having different truncation percentages as part of window fa ade has been investigated. Truncation of the tilted CPC is done with eight different percentages relative to the complete CPC. The resulting truncated segments are ray traced and their collection efficiency and concentration ratio are calculated. Total transmitted solar radiation and the generated electricity are predicted based on a realistic profile of solar radiation over a day. (C) 2013 Elsevier B.V. All rights reserved.