Solar Energy Materials & Solar Cells 91 (2007) 453–459 Experimental evaluation of V-trough (2 suns) PV concentrator system using commercial PV modules C.S. Sangani, C.S. Solanki à Energy Systems Engineering, IIT Bombay, Powai, Mumbai 400076, India Received 2 July 2006; received in revised form 19 September 2006; accepted 6 October 2006 Available online 22 November 2006 Abstract V-trough photovoltaic (PV) concentrator systems along with conventional 1-sun PV module is designed and fabricated to assess PV electricity cost ($/W) reduction. V-trough concentrator (2-sun) system is developed for different types of tracking modes: seasonal, one axis north–south and two axes tracking. Three design models based on these tracking modes are used to develop the V-trough for a 2-sun concentration. Commercially available PV modules of different make and types were evaluated for their usability under 2-sun concentration. The V-trough concentrator system with geometric concentration ratio of 2 (2-sun) increases the output power by 44% as compared to PV flat-plate system for passively cooled modules. Design models with lower trough angles gave higher output power because of higher glass transmittivity. PV modules with lower series resistance gave higher gain in output power. The unit cost ($/W) for a V-trough concentrator, based on different design models, is compared with that of a PV flat plate system inclined at latitude angle (Mumbai, f ¼ 19.121). r 2006 Elsevier B.V. All rights reserved. Keywords: PV; Concentrators systems; Non-imaging concentrators; Low concentration; V-trough 1. Introduction Solar photovoltaic (PV) technology is a very attractive renewable energy option for clean energy generation but is limited in use due to its prohibitively high cost. However, the cost of PV power generation has decreased substan- tially over the last two decades, and now stabilized, in fact, slightly increased in recent years to a value, which is still quite high as compared to the cost of other conventional power generation technologies as well as non-conventional technology such as wind energy technology. The PV cell material contributes about 50% of the total cost of PV system. The cost of PV modules has started increasing since last 2 years due to material shortage in the market. The cost has actually increased from 4.95 to 5.35 US $/W in 2005–2006 [1]. Measures are required to reduce the PV power generation cost by reducing the material consump- tion for widespread commercialization of PV technology. There are several ways by which the PV material consumption/watt of generated power can be reduced. These include use of thinner wafer, thin-film solar cell technologies and concentrator PV technologies. In the PV concentrator technology, the use of optical concentrators replaces the expensive PV cell area by cheaper reflector material, hence reducing the material consumption. Com- pared to the non-concentrating PV, the required area of the solar cell is reduced by the factor of concentration ratio, providing significant reduction in the cost of PV system. Although the concept of use of solar PV concentrator with PV modules/cells is simple but it is difficult to implement, especially for high concentration ratio. High concentration ratio puts stringent constraints on solar PV cell, heat dissipation and sun tracking. However, it is possible to use commercially available solar PV modules with low concentration optics in static or quasi-static mode wherein the need of continuous tracking is eliminated. Based on the above concepts, V-trough concentrator is an attrac- tive option to reduce the price of the PV electrical power using conventional solar PV cells. V-trough’s are static ARTICLE IN PRESS www.elsevier.com/locate/solmat 0927-0248/$ - see front matter r 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.solmat.2006.10.012 à Corresponding author. Tel.: +91 22 2576 7895; fax: +91 22 2576 4890. E-mail address: chetanss@iitb.ac.in (C.S. Solanki).