Outdoor environmental variability ingenerates the need for indoor systems for PV module characterisation. To combine the advantages of the most commonly used simulators (steady-state and pulsed) and eliminate their disadvantages, an LED-based solar simulator prototype has been developed.The system can produce light at variable flash speeds and pulse shapes or can operate as a continuous light source for long-term measurements. The system achieves one sun intensity at a closely matched, continuous spectrum. Full control of all light sources allows variable intensity and spectral distribution during measurements. A technical description and results of initial qualification tests are given.

The effects of different spectra on the laboratory based performance evaluation of amorphous silicon solar cells is investigated using an opto‐electrical model which was developed specifically for this purpose. The aim is to quantify uncertainties in the calibration process. Two main uncertainties arise from the differences in the test spectrum and the standard spectrum. First, the mismatch between reference cells and the measured device, which is shown to be voltage dependent in the case of amorphous silicon devices. Second, the fill factor of the device is affected by different spectra. Different cell structures and states (specifically different i‐layer thickness and levels of degradation) for the different light sources are investigated in this work. These sources are different solar simulators, LED sources, Tungsten as well as the standard terrestrial AM1.5G radiation. It is shown that the performance cannot be evaluated by short circuit current alone. The voltage dependent quantum efficiency of p‐i‐n devices can introduce a mismatch in the PMPP of 1% for 250 nm i‐layer devices in as prepared state, rising to up to 4% for the 600 nm i‐layer devices at degraded state. Copyright © 2011 John Wiley & Sons, Ltd.

The use of a Mo–N barrier for solution-processed CIGS results in reduced MoSe2 formation. This enabled longer selenization time, enhanced grain growth and performance.

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The effects of regionalism on trade have been extensively evaluated within a gravity model framework. With the expected exit of the United Kingdom (UK) from the European Union (EU), the prospect of regional disintegration has brought about a new impetus to studying trade policy effects. Using actual and forecast data for a panel of bilateral imports between the EU15 and the rest of the world, this paper examines the trade effects of EU economic integration agreements (EIAs), their evolution over time and the related counterfactual Brexit trade policy scenarios. Distinct trade effects are obtained for the EU trade related agreements; positive, significant and of similar magnitude for the EU and free trade agreement (FTA) coefficients, but negative and significant (and smaller in magnitude) for the regional economic partnership agreements (EPAs). The subperiod results suggest the positive coefficients of EU and FTA membership tend to diminish over time, implying earlier membership of EIAs came with greater trade benefits. Finally, in generating the predicted values for the trade effects of three alternative counterfactual Brexit scenarios (hard Brexit, hard Brexit plus, global Britain), the findings suggest an asymmetric effect depending on the perspective of the UK versus the EU. Whereas the UK's trade would decline substantially with all three country groups (the EU, the FTAs and regional EPAs) and rise substantially with the rest of the world, only minor percentage changes are predicted for EU bilateral trade.

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A system that combines the advantages of fast global electroluminescence (EL) imaging and detailed spectrally resolved EL measurements is presented. A charge-coupled device camera-based EL imaging system is used to measure the intensity of radiative recombination of the photovoltaic (PV) device spatially resolved over its full area. A monochromator-based system is utilised to measure localised emission spectra at given points of interest. Measurements of multi-crystalline and amorphous silicon PV devices demonstrate the potential to investigate radiative defects and reveal performance variations and non-uniformities. This links inhomogeneities much closer to device physics than using camera-based EL only.