Effect of tilt angle and connection mode of PVT modules on the energy efficiency of a hot water system for high-rise residential buildings

The tilt angle and connection mode of PVT modules are critical factors influencing the energy efficiency of PVT systems. To evaluate their effect, we built a PVT hot water system which is naturally driven by gravity and the PVT modules are installed on vertical facades of high-rise residential buildings. We develop a dynamic model for the simulation of the PVT hot water system. The simulation results are in good agreement with indoor experimental data. Compared with parallel connection, electric power for series connection decreases by 2.0%, thermal energy increases by 11.4% and total energy increases by 5.4%. The connection mode has more obvious influences on thermal energy than electrical power. Considering only total energy, PVT modules with a tilt angle of 20° can produce maximum energy benefits. However, the projection lengths of PVT modules should also be considered when selecting the optimum tilt angle. The optimum tilt angle is chosen as 40° when both total energy and projection length are considered. These findings are good references for the installation of PVT modules on vertical facades of high-rise residential buildings.

[1]  William E. Boyson,et al.  Photovoltaic array performance model. , 2004 .

[2]  Saffa Riffat,et al.  Performance evaluation and techno-economic analysis of a novel building integrated PV/T roof collector: An experimental validation , 2014 .

[3]  Tin-Tai Chow,et al.  A Review on Photovoltaic/Thermal Hybrid Solar Technology , 2010, Renewable Energy.

[4]  Eric Savory,et al.  Numerical modelling of forced convective heat transfer from the inclined windward roof of an isolated low-rise building with application to photovoltaic/thermal systems , 2011 .

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

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

[7]  Vytautas Martinaitis,et al.  Evaluation of energy efficiency measures sustainability by decision tree method , 2014 .

[8]  Vassilis Belessiotis,et al.  Assessment of uncertainty in solar collector modeling and testing , 1999 .

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

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

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

[12]  Patrick Dupeyrat,et al.  The PHOTOTHERM Project: Full Scale Experimentation and Modelling of a Photovoltaic – Thermal (PV-T) Hybrid System for Domestic Hot Water Applications , 2014 .

[13]  Wei He,et al.  Operational performance of a novel heat pump assisted solar façade loop-heat-pipe water heating system , 2015 .

[14]  Fang Tang,et al.  Dynamic characteristics modeling of a hybrid photovoltaic–thermal solar collector with active cooling in buildings , 2014 .

[15]  Kattathu Joseph Mathew,et al.  Guide to the expression of uncertainty in measurements , 2017 .

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

[17]  Tin-Tai Chow,et al.  Hybrid photovoltaic and thermal solar-collector designed for natural circulation of water , 2006 .

[18]  Zhiqiang John Zhai,et al.  Experimental and numerical investigation on thermal and electrical performance of a building integrated photovoltaic–thermal collector system , 2010 .

[19]  Morgan Bazilian,et al.  Photovoltaic cogeneration in the built environment , 2001 .

[20]  J. Fernandes,et al.  Hybrid photovoltaic/thermal (PV/T) solar systems simulation with Simulink/Matlab , 2010 .

[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 .

[23]  K. F. Fong,et al.  Annual performance of building-integrated photovoltaic/water-heating system for warm climate application , 2009 .

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

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

[26]  Liangliang Sun,et al.  Optimum design of shading-type building-integrated photovoltaic claddings with different surface azimuth angles , 2012 .

[27]  D. L. King,et al.  Temperature coefficients for PV modules and arrays: measurement methods, difficulties, and results , 1997, Conference Record of the Twenty Sixth IEEE Photovoltaic Specialists Conference - 1997.