Optimum connection modes for photovoltaic thermal collectors in different radiation zones of China

Abstract The connection mode of photovoltaic thermal (PVT) collectors is critical factor influencing the performance of PVT system. While determining optimum connection modes for PVT collectors in different radiation zones has not been previously reported in published literatures. In this study, a dynamic heat transfer model representing different connection modes for a PVT hot water system was developed, validated, and applied. By considering the ambient temperature, solar radiation, and heating load concurrently, the optimum connection mode in 10 different cities was determined based on an optimization index of realized combined electrical energy. The results indicated that the connection modes corresponding to the maximum realized combined electrical energy were N  = 2 and N  = 3 in radiation zone II and III, respectively, where N is the number of collectors in series. In Shantou, high ambient and main water temperatures contributed to a 40 MJ increase in the realized combined electrical energy when the connection mode changed from N  = 3 to N  = 2. The results of this study provide good guidance for determining optimum connection modes for PVT hot water systems in different radiation zones.

[1]  Liu Yang,et al.  Solar radiation modelling using ANNs for different climates in China , 2008 .

[2]  Fang Tang,et al.  Performance evaluations and applications of photovoltaic–thermal collectors and systems , 2014 .

[3]  H. Pierrick,et al.  Dynamic numerical model of a high efficiency PV–T collector integrated into a domestic hot water system , 2015 .

[4]  Jie Ji,et al.  Effect of fluid flow and packing factor on energy performance of a wall-mounted hybrid photovoltaic/water-heating collector system , 2006 .

[5]  Swapnil Dubey,et al.  Analysis of PV/T flat plate water collectors connected in series , 2009 .

[6]  W. Beckman,et al.  Solar Engineering of Thermal Processes , 1985 .

[7]  Zhaohui Lin,et al.  Climate of China , 1992 .

[8]  Kamaruzzaman Sopian,et al.  Photovoltaic-thermal (PV/T) technology – The future energy technology , 2013 .

[9]  D. Loveday,et al.  Convective heat transfer coefficients at a plane surface on a full-scale building facade , 1996 .

[10]  Songqiao Zhao,et al.  Physical geography of China , 1986 .

[11]  Christos N. Markides,et al.  Dynamic coupled thermal-and-electrical modelling of sheet-and-tube hybrid photovoltaic/thermal (PVT) collectors , 2016 .

[12]  Chris Bales,et al.  External DHW units for solar combisystems , 2003 .

[13]  Liangliang Sun,et al.  Effect of tilt angle and connection mode of PVT modules on the energy efficiency of a hot water system for high-rise residential buildings , 2016 .

[14]  Lei Cao,et al.  Dynamic performances modeling of a photovoltaic–thermal collector with water heating in buildings , 2013 .

[15]  Soteris A. Kalogirou,et al.  Photovoltaic thermal (PV/T) collectors: A review , 2007 .

[16]  Shyam,et al.  Analytical expression of temperature dependent electrical efficiency of N-PVT water collectors connected in series , 2015 .

[17]  Rohit Tripathi,et al.  Energetic and exergetic analysis of N partially covered photovoltaic thermal-compound parabolic concentrator (PVT-CPC) collectors connected in series , 2016 .

[18]  Zhixin Wang,et al.  Solar energy development in China--A review , 2010 .

[19]  J. Michalsky,et al.  Modeling daylight availability and irradiance components from direct and global irradiance , 1990 .

[20]  Tin-Tai Chow,et al.  An experimental study of façade-integrated photovoltaic/water-heating system , 2007 .

[21]  Kamaruzzaman Sopian,et al.  Performance analysis of PV/T Combi with water and air heating system: An experimental study , 2016 .

[22]  Xingxing Zhang,et al.  Review of R&D progress and practical application of the solar photovoltaic/thermal (PV/T) technologies. , 2012 .