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Bifacial crystalline Silicon (Si) photovoltaic (PV) devices are attracting considerable interest from manufacturers and the market since they can enhance the performance in comparison with traditional monofacial PV devices. Technical specification IEC TS 60904-1-2 was published in 2019 and proposes several characterization methods for bifacial PV device testing based on single-side, double-sided and natural sunlight illumination. This article analyses the advantages, disadvantages, the suitability and the feasibility of the different methods and compares the electrical performance obtained by the proposed approaches at the European Solar Test Installation for the testing of bifacial Si devices. Deviations in Pmax below 0.9% for the different testing methods under test was obtained except for the double-source approach with a rear reflector (2.59%) where the measurement of the rear irradaince influence the P max.

Bifacial c-Si photovoltaic (PV) modules can increase the performance of traditional PV modules because both sides of the cells, front and rear, absorb solar radiation. The knowledge of the temperature coefficients (TCs) is relevant to compare indoor and on-field performance of PV devices. In this paper, the TCs of c-Si bifacial PV modules from five different manufacturers were measured under natural sunlight and simulated indoor condition with a large-area steady-state solar simulator and the data were compared with the datasheet values. The effects on the TCs of an opaque and a reflective rear cover were also analyzed. There were no relevant differences between indoor and outdoor and for front and rear side TCs (within the measurement uncertainty). Slight differences with respect to the datasheet values were found for most of the modules under test for the TC for current α and for maximum power δ coefficients. However, since the manufacturers do not declare the TC uncertainty, a definitive statement cannot be made.

An electrical resistivity monitor for the detection of composition changes in the lithium-lead eutectic alloy, Pb17Li, has been developed. A miniature electromagnetic pump is used to sample alloy continuously from a pool or loop system and force it through a capillary section, within which the necessary resistance measurement are made, prior to its return to the bulk source.

The saturation solubilities of nickel and manganese in Pb17Li have been measured over the temperature range of interest for the use of Pb17Li as a coolant and tritium breeder in fusion reactors. Nickel was found to have a particularly high solubility in Pb17Li as given by the equation: Log10S(wppm) = 4.832−981.2/T(K) for T= 520−728 K. The solubility of nickel in pure lead was also determined and found to be in good agreement with literature data. The solubility of manganese was found to be much lower than that of nickel in Pb17Li and is given by the equation: Log10s(wppm) = 6.732−2938/T(k) for T= 531−783 K. The solubility of chronium was found to be very low and the data subject to too much scatter to be fitted to a sensible equation. The possibility of interference by oxygen dissolved in the Pb17Li is discussed. Equilibration measurements of the dissolution of Ni, Cr, Mn and Fe from Type 316 stainless steel are also described.