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In this study, we have investigated a hybrid thin film PV vacuum glazing called: ‘PV VG-4L’. The glazing involves an integration between a thin film PV glazing with a double vacuum glazing (both manufactured independently), and an additional layer of self-cleaning coated glass which totalling four layers of glass. The mathematical model of the PV VG-4L designs were developed and 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 conditions. Lab-scale experiments were conducted at steady state conditions using a TEC driven calibrated hot box at the Sustainable Energy Research Lab, University of Nottingham, UK. Meanwhile, outdoors, the prototype was tested at a research house at the University of Nottingham, UK. Under the influence of solar irradiance, the electrical performance of the PV-VG and the temperature difference between the surfaces of the glazing were analysed. However, the measurement of U-value under real conditions is not reliable due to the influence of solar irradiance on the heat flux sensor and also due to the absorbed solar irradiance by the thin film PV layer. Nevertheless, during low to zero solar irradiance, the U-value of the prototype can be estimated. The developed model was then validated against the experimental results by direct comparison to the trend of the experimental and theoretical curves obtained, and also by conducting error analysis using root mean squared percentage deviation (RMSPD) method. Testing using the calibrated hot box, adhering closely to ISO 12567 standards, resulted in an average measured total U-value of 0.6 W/m²K which is when compared to a single thin film PV glazing with a typical U-value of 5 W/m²K; the U-value is higher by almost 90%. From the analysis, the computed RMSPD value for the glazing surface temperature and the U-value are 4.02% and 0.92% respectively. Meanwhile, field testing under real conditions with a 0.4 m × 0.4 m PV VG-4L prototype found that 14 W/m² power can be generated by the PV VG-4L at average solar irradiance of ~600 W/m². RMSPD computed glazing surface temperatures, electrical power generated under real conditions and U-value are 2.90%, 8.70% and 2.89% respectively. The theoretical and experimental results are concluded to be in good agreement. This study has significant contributions to the knowledge of building integrated photovoltaic PV technology. The mathematical model that has been developed can be used for PV VG-4L design optimisation and also to simulate the performance of PV VG-4L under various conditions. 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 its range of potential applications which can be improved depending on the energy needs and applications, such as for BIPV solar façade (PV curtain walling) in commercial buildings, greenhouses, skylight and conservatory [ABSTRACT FROM AUTHOR]

Large-scale full solar spectrum irradiation system is an important part of the solar simulator. Irradiation non-uniformity is one of the key technical indexes for the large-scale solar simulator. Some technical problems about difficultly meeting the national standard and the poor optical spectra matching property of light sources exist in traditional solar simulators. Regarding the present issues of the large-scale solar simulators, a full-spectrum irradiation system was designed, and the irradiation uniformity of the system was simulated by using the software Zemax. An innovative concept, irradiance decay pattern, is put forward, and the irradiation uniformity is optimized in this way. A plasma light source produced by Solaronix, Switzerland is used, and the spectrum of full-spectrum solar irradiation system can reach Level A of IEC standard. The irradiance of the proposed system was tested by using a spectral radiometer in the full-spectrum scope. The test results show, when the irradiance is 280 W/m2, the irradiance nonuniformity is 5. 7% if the irradiance decay pattern is switched on, or 8. 4% if the pattern is off. Referring to the national standard GB/T12637—90 General specification for solar simulator, in the effective radiation area of 2 400 mm × 6 000 mm, the irradiance uniformity is better than Level C, and almost reaches Level B. [ABSTRACT FROM AUTHOR]

Fabrication of efficient Pb reduced inorganic CsPbI2Br perovskite solar cells (PSC) are an important part of environment‐friendly perovskite technology. In this work, 10% Pb reduction in CsPb0.9Zn0.1I2Br promotes the efficiency of PSCs to 13.6% (AM1.5, 1sun), much higher than the 11.8% of the pure CsPbI2Br solar cell. Zn2+ has stronger interaction with the anions to manipulate crystal growth, resulting in size‐enlarged crystallite with enhanced growth orientation. Moreover, the grain boundaries (GBs) are passivated by the Cs‐Zn‐I/Br compound. The high quality CsPb0.9Zn0.1I2Br greatly diminishes the GB trap states and facilitates the charge transport. Furthermore, the Zn4s‐I5p states slightly reduce the energy bandgap, accounting for the wider solar spectrum absorption. Both the crystalline morphology and energy state change benefit the device performance. This work highlights a nontoxic and stable Pb reduction method to achieve efficient inorganic PSCs. [ABSTRACT FROM AUTHOR]