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Bifacial technology is attracting the attention of the photovoltaic community. Although considered premature, research and development activities still need to be carried out to improve bPV performance. In addition, the need for a standard test reference will aid bankability and increase confidence in this technology. This article describes the state of the art of bifacial technology, going through the bPV cell and its difference compared to conventional monofacial cells and listing the different sources of limitations, with an identification of different parameters that characterize the performance of the bifacial. Then, the paper reviews the different modeling methods that allow predicting the performance of bPV systems, and ends with the most important applications, whether for dual use of land to produce energy and food (agrivoltaic) or for placing bPV modules on water bodies instead of on the ground (aquavoltaics), or for vertical use as solar fences, acoustic barriers, or building-integrated photovoltaic modules. [ABSTRACT FROM AUTHOR]

This work connects the electrical performance and economics of High Concentrator Photovoltaic technology beyond the cell and module levels. It analyses the impact of fundamental variables on the calculated energy output and economics of a typical system for real-world solar power plants in five locations with diverse climatic conditions. It was found that there exists a nearly linear relationship between the Final Energy Yield and the average direct normal irradiance, while the cell temperature and spectral AC energy losses ranged from 4.6% to 1.8% and 5.0%–2.4%. The LCOE (Levelised Cost of Electricity) calculations used these insights, together with the specific economic values for each location. The results show that the locations with the higher annual energy yield tend to have the lower LCOE values. In particular, the LCOE ranged from 5.5 c€/kWh to 22.2 c€/kWh for a conservative scenario. However, the sites with the highest final yield do not necessarily present the lowest values of LCOE. The results emphasize the interrelationship between the instantaneous effects of cell temperature and spectrum on the performance of the system, as well as the importance of considering the specific economic parameters to estimate the LCOE at each location. [ABSTRACT FROM AUTHOR]

The IEC 62670-3 standard recommends the open-circuit voltage method to calculate the cell temperature inside high-concentrator photovoltaic (HCPV) modules. This method requires knowledge of the temperature coefficient of open-circuit voltage ( β ), and the same standard provides a procedure to get this parameter. In this paper, an alternative method for the thermal characterisation of HCPV modules is proposed. As an advantage, it allows obtaining both the β parameter and the internal thermal resistance ( ρ ) of the device from outdoor measurements. No internal sensor for measuring the cell temperature is required as in the case of the IEC 62670-3 standard. Knowing the ρ parameter allows a more accurate characterisation of the cell temperature. The proposed procedure is applied to a real HCPV module. An outdoor experimental campaign of two months in Jaén (Southern Spain) was carried out. The β value was underestimated in a 0.50% and the ρ value was overestimated in a 4.18%. When applying the estimated parameters for the prediction of the cell temperature, the open-circuit voltage method gave a root mean square error (RMSE) of 1.41 °C, while the internal thermal resistance method gave a RMSE of 0.62 °C. [ABSTRACT FROM AUTHOR]

Non-uniformity is a relevant concern of concentrator photovoltaic systems (CPV) due to its impact on the performance of multi-junction (MJ) solar cells. This work is focused on a state-of-the-art investigation related to the effects of shading on the irradiance profiles and electrical performance of MJ cells. For doing this, three different CPV single-units with a concentration of ≈559x have been experimentally investigated indoors at the CPV laboratory of the University of Jaén. The units are made up of poly(methyl methacrylate) (PMMA) Fresnel lens and standard GaInP/GaInAs/Ge MJ cells. Also, single-lens-optical element (SILO-Pyramid) and refractive truncated pyramid (RTP) homogenizers have been considered. The results indicate that shading produces additional spatial and spectral non-uniformities, and that these are reduced by the use of homogenizers. In addition, the non-uniform spectral illumination has been identified as the main cause of the additional reduction of the performance of MJ solar cells. In this sense, the SILO-Pyramid provides the best results and shows a significantly stable spectral performance under shading conditions. For a no-homogenizer case, the maximum power shows a reduction of 86.3% for a shading factor of 80%, while it is only reduced by 83.2% and by 81.6%, respectively, for the RTP and SILO-Pyramid. • Non-uniformity on multi-junction solar cell caused by shading is investigated. • Different types of refractive homogenizers are considered. • Shading is produced on the surface of a Fresnel lens by using opaque masks. • Electrical measurements and charge-coupled device camera photographs are used. • Results will help to propose strategies to mitigate non-uniformities under shading. [ABSTRACT FROM AUTHOR]