Seasonal power fluctuations of amorphous silicon thin-film solar modules: distinguishing between different contributions

Abstract

Several works report on seasonal fluctuations of power production of amorphous silicon (a-Si). These oscillations are due to two overlapping phenomena (i) spectral and (ii) the Staebler-Wronski effects. It is hence difficult to assess-for a given location and climatic conditions-which one has the largest impact. By means of a straightforward approach based on two sets of singlejunction a-Si photovoltaic modules (stored indoors/exposed outdoors) and on two different I-V measurement set-ups (indoor and outdoor), we were able to separate the different contributions to this phenomenon. For the test-site of Lugano, seasonal oscillations account for performance variations of a-Si of~10% (AE5% around an annual average value with a minimum around the mid of January and a maximum around mid-July). The time-phase of the overall effect lies in between that of the two distinguished phenomena. (i) Spectral variations seem to have the highest impact on the outdoor performance of a-Si with an amplitude corresponding to 10.5% (AE~5.2%). Moreover, the influence of spectral variations on the outdoor performance of a-Si (and for comparison of c-Si) was modeled, and the experimental data were found to be in excellent agreement with the theoretical simulation; (ii) the Staebler-Wronski effect has a slightly lower influence with an amplitude of~8% (AE4% with a minimum at the middle of February and a maximum around mid-August). Because of the position (46 N) and average climatic conditions (southern Alpine climate) of Lugano, these observations are possibly representative of a large part of continental Europe.

PV technologies performance comparison in temperate climates

“…In addition, as is well known and as previously introduced, the spectral composition of the incident solar radiation has a great influence on the seasonal variation of the PR, with particular reference to the products with a layer of amorphous silicon (Virtuani and Fanni, 2014;Gottschalg et al, 2003). Amorphous silicon, in fact, has a narrow spectral response (250-800 nm) and thus is more sensible to the blue components of the spectrum, in comparison with the spectrum response of c-Si (350-1200 nm).…”

Power change in amorphous silicon technology by low temperature annealing

“…Second it is at temperatures measured as operation temperatures in the field. As it has been observed as a seasonal effect seen in building integrated a-Si technologies, where the power of the PV modules improves during summer and decreases during winter season [21]. Therefore, it was interesting to use outdoor operating temperatures of PV modules in dark to observe the effect of low temperature on the recovery of power.…”

A Prototype Design and Development of the Smart Photovoltaic System Blind Considering the Photovoltaic Panel, Tracking System, and Monitoring System

“…According to previous studies, the performance of the electricity generation of the PV system was enhanced in the order of the dual-axis tracker type, single-axis tracker type, and fixed type [19][20][21][22]. To improve the performance of the electricity generation of the SPSB, the application of the tracker is required.…”

“…Lazaroiu et al [19], Cruz-Peragón et al [20], and Virtuani and Fanni [21], Heslop and Macgill [22], Mousazadeh et al [23], and Dolara and Mussetta [24] performed comparative analyses on the electricity generation of the PV system according to the tracker type. In these previous studies, the performance of the electricity generation on the PV panel was found to be carried out in the order of the dual tracker, single tracker, and fixed type.…”