Performance Analysis of an integrated Semi-TransparentThin Film PV Vacuum Insulated Glazing
This paper is intended to design and develop a thermal model of an integrated semi-transparent thin-film PV vacuum glazing with four layers of glass called PV VG-4L. The design of the glazing involves integration between a thin-film PV glazing with a dou-ble vacuum glazing (both manufactured independently), and an additional layer of self-cleaning coated glass. For the mathematical model, the energy balance equations were derived for the thin-film PV glass, the glass panes of the vacuum glazing and the edges of the internal and external glass surfaces (facing indoors and outdoors respectively). The model was numerically solved in MATLAB. To evaluate the performance of the PV VG-4L, the prototype was manufactured and investigated at lab-scale and also under real condi-tions. At lab-scale, experiments were conducted at steady-state conditions using a TEC driven calibrated hot box at Sustainable Energy Research Lab, University of Nottingham, UK. Meanwhile, outdoors, the prototype was tested at a research house at the University of Nottingham, UK. The developed model was then validated against the experimental results by direct comparison on the trend of the experimental and theoretical curves ob-tained, and also by conducting error analysis using root mean squared percentage deviation (RMSPD) method. When tested using the calibrated hot box, by following closely the ISO 12567 standards, the average measured total U-value is 0.6 W/m2K. From the analysis, the computed RMSPD value for the glazing surface temperature and the U-value are 4.75 % and 0.96% respectively. The RMPSD computed for the glazing surface temperatures, electrical power generated under real conditions and U-value are 2.58 %, 1.4% and 6.86 % respectively. The theoretical and experimental results are concluded to be in good agree-ment. The thermal and electrical performance of a building retrofitted with and without PV VG-4L was examined and discussed. At building efficiency level, the PV VG-4L not only can produce power, but it also has high insulating properties. The promising U-value implies that the glazing’s range of potential applications can be improved depending on the energy needs and applications, which includes its use in BIPV solar façades (PV curtain walling) for commercial buildings, greenhouses, skylights and conservatories.
Semi-transparent thin-film PV; Low U-value; SHGC.
2. Markets, R.a. $7 Bn Building Integrated Photovoltaics (BIPV) Market - Global Outlook and Forecast 2019-2024.
2019 [cited 2019 14 October]; Available from: https://www.globenewswire.com/news-release/2019/02/08/1713914/0/en/7-Bn-Building-Integrated-Photovoltaics-BIPV-Market-Global-Outlook-and-Forecast-
3. Martín-Chivelet, N., et al., Comparative Performance of Semi-Transparent PV Modules and Electrochromic
Windows for Improving Energy Efficiency in Buildings. Energies, 2018. 11(6): p. 1526.
4. Liu, H.-M., et al., Improving the Performance of a Semitransparent BIPV by Using High-Reflectivity Heat Insulation
Film. International Journal of Photoenergy, 2016. 2016: p. 15.
5. Zhang, W., L. Lu, and X. Chen, Performance Evaluation of Vacuum Photovoltaic Insulated Glass Unit. Energy
Procedia, 2017. 105(Supplement C): p. 322-326.
6. Ghosh, A., S. Sundaram, and T.K. Mallick, Investigation of thermal and electrical performances of a combined
semi-transparent PV-vacuum glazing. Applied Energy, 2018. 228: p. 1591-1600.
7. Schott, T. Operational temperatures of PV modules. in 6th PV solar energy conference. 1985.
8. Evans, D., Simplified method for predicting PV array output. Solar Energy, 1981. 27: p. 555–560.
9. JARIMI, H., et al. An affordable small calibrated hot box suitable for thermal performance measurement of a
glazing unit. in 17th International Conference on Sustainable Energy Technologies 21st to 23rd August 2018. 2018.
10. EDTM. EDTM SS2450 | Solar Spectrum Meter. 2019 [cited 2019 14 July 2019]; Available from: https://www.edtm.com/index.php/ss2450-solar-spectrum-meter.
11. Moralejo Vázquez, F.J.a.M.C., Nuria and Olivieri, Lorenzo and Caamaño Martín, Estefanía Optical characterisation of semi-transparent PV modules for building integration., in 29th European Photovoltaic Solar Energy Conference and Exhibition (EU PVSEC 2014). 2014: Amsterdam, The Netherlands. . p. 1-9.
12. Liu, L., Investigation on solar/thermoelectric collector for building application, in Department of Architecture and Built Environment. 2014, University of Nottingham: UK.
13. bsi, BS EN ISO 52016-1:2017 Energy performance of buildings. Energy needs for heating and cooling, internal temperatures and sensible and latent heat loads. Calculation procedures. 2017.
14. CIBSE, GVA/15 CIBSE Guide A: Environmental Design 2015. 2015: CIBSE. 402.
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
All the intellectual property rights of the papers accepted for the publication belong to the Hittite Journal of Science & Engineering.