PV Module Temperature Prediction at Any Environmental Conditions and Mounting Configurations

Photovoltaic (PV) module temperature is known to significantly affect its power output and efficiency, while it has been shown to depend mainly on the ambient temperature, the solar irradiance incident on the PV plane and the wind speed, while to a lesser extent on the wind incidence angle and various other environmental parameters as well as PV module structural characteristics, module type, etc. The mounting configuration has been shown to play a significant role in the PV temperature developed and the power output. This paper presents an algorithmic approach for the prediction of PV module temperature at any environmental conditions based on the energy balance equation taking into account PV orientation, windward and leeward side, heat convection by natural and air forced flow, heat conduction and the radiated heat by the PV module. The results are compared to measured data under various outdoor conditions of ambient temperature, solar irradiance and wind speed. In addition, the predicted PV temperature is compared to predicted values from existing models. The robustness of the simulation algorithm developed in the prediction of PV module temperature is presented and its clear advantage over empirical models, which are fine-tuned for the exact experimental conditions and/or experimental set-ups under which they were developed, is illustrated. Furthermore, the coefficient f which relates the PV module temperature with the solar irradiance on the PV plane and the ambient temperature is examined for various configurations of free-standing fixed and sun-tracking PV system as well as building integrated photovoltaic (BIPV), illustrating essential differences in this and in the temperature developed in the PV module.

[1]  Eleni Kaplani,et al.  On the relationship factor between the PV module temperature and the solar radiation on it for various BIPV configurations , 2014 .

[2]  Govindasamy Tamizhmani,et al.  Photovoltaic Module Thermal/Wind Performance: Long-Term Monitoring and Model Development for Energy Rating , 2003 .

[3]  A J Anderson,et al.  Photovoltaic translation equations: A new approach. Final subcontract report , 1996 .

[4]  W. Beckman,et al.  Solar Engineering of Thermal Processes: Duffie/Solar Engineering 4e , 2013 .

[5]  Eleni Kaplani,et al.  Intelligent energy buildings based on RES and nanotechnology , 2015 .

[6]  M. Heck,et al.  Modeling of the nominal operating cell temperature based on outdoor weathering , 2011 .

[7]  Ernani Sartori,et al.  Convection coefficient equations for forced air flow over flat surfaces , 2006 .

[8]  David Faiman,et al.  Assessing the outdoor operating temperature of photovoltaic modules , 2008 .

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

[10]  Gilles Notton,et al.  Calculation of the polycrystalline PV module temperature using a simple method of energy balance , 2006 .

[11]  M. J. Wheeler.  Heat and Mass Transfer , 1968, Nature.

[12]  E. Skoplaki,et al.  ON THE TEMPERATURE DEPENDENCE OF PHOTOVOLTAIC MODULE ELECTRICAL PERFORMANCE: A REVIEW OF EFFICIENCY/ POWER CORRELATIONS , 2009 .

[13]  S. Churchill.  A comprehensive correlating equation for laminar, assisting, forced and free convection , 1977 .

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

[15]  Eleni Kaplani,et al.  Thermal modelling and experimental assessment of the dependence of PV module temperature on wind velocity and direction, module orientation and inclination , 2014 .

[16]  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.