**1. Introduction**

440 Solar Cells – Thin-Film Technologies

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Todorov, T. K., Reuter, K.B. & Mitzi, (2010). High Efficiency Solar Cell with Earth-Abundant Liquid-Processed Absorber. *Advanced Materials* 22, pp. E156-159. ISSN 1121-4095. Townsend, S.W., Ohno, T.R., Kaydanov, V., Gilmore, A.S., Beach, J.D. & Collins, R.T. (2001).

von Roedern, B. & del Cueto, J.A. (2000). Model for Staebler-Wronski Degradation Deduced

Wanlass, M.W. & Albin, D.S., (2004). A Rigerous Analysis of Series-Connected, Multi-

Whitaker, C.M., Townsend, T. U., Wenger, H. J., Illiceto, A., Chimento, G. & Paletta, F. (1991).

Yan, B., Yue, G. & Guha, S., (2007). Status of nc-Si :H Solar Cells at United Solar and Roadmap

von Roedern, B. (2006). Thin Film PV Module Review. *Refocus magazine (Elsevier) (July + August* 

Wohlgemuth, J.H., Cunningham, D.W., Monus, P., Miller, J. & Nguyen, A., (2006). Long- term

Francisco, CA 16-20.4.2001), pp. H5.11.1-6. ISBN 1-55899-604-4

694. ISBN 0-7803-3767-0

shown on pages 2 & 3 in Figures 2 & 3

ISSN 0021-8979

0160-8371

55899-517-X

0-7354-02221

55899-949-7

ISBN 1-4244-0017-1

pp. 608-613. ISBN 0-87942-635-7

*2006)* pp. 34-36. ISSN 1471-0846 Wohlgemuth, J.H. (2010). private communication

*26th IEEE Photovoltaic Specialists Conference,* (Anaheim, CA, 29.9-3.10.1997), pp. 691-

heterojunctions on the basis of CuInSe2. *Journal of Applied Phys*ics 73, pp. 2902-2909.

Schade, H. & Chao, H. W. A. (1988). a-Si:H Films Deposited at High Rates in 'VHF' Silane Plasma : Potential for Low-Cost Solar Cells. *Conference Record of the 20th IEEE Photovoltaic Specialists Conference,* (Las Vegas, NV 26-30.9.1988), pp. 282-287. ISSN

Thin-Film Modules, NREL/TP-413-8121. The fabrication sequence of Siemens Solar is

The Influence of Stressing at Different Biases on the Electrical and Optical Properties of CdS/CdTe Solar Cells.. *Materials Research Society Symposia Proceedings* 668 (San

from Long-Term, Controlled Light-Soaking Experiments. *Mataterials Research Society Symposia Proceedings* 609, (San Francisco, CA24-28.4.2000), pp. A10.4.1-6. ISBN 1-

Bandgap, Tandem Thermophotovoltaics (TPV) Energy Converters. *Proceedings of the 6th Conference on Thermophotovoltaic Generation of Electricity,* (Freiburg, Germany 14- 16.6.2004), American *Institute of Physics Conference Proceedings* 738, pp. 462-470. ISBN

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for Manufacturing a-Si :H and nc-Si :H Based Solar Panels. *Materials Researchy Society Symposia Proceedings* 989 (San Francisco, CA, 9-13.4.2007), pp. 335-346. ISBN 978-1-

reliabilty of photovoltaic modules. *Conference Record of the 2006 IEEE 4th World Conference on Photovoltaic Energy Conversion* (Waikoloa, HI 7-12.5.2006), pp. 2050-2053. The effect of spectral distribution on the performance of photovoltaic (PV) modules is often neglected. The introduction of multi-junction devices such as Copper Indium Diselenide (CIS) necessitated a concerted investigation into the spectral response on these devices. In part this attributed to the wider spectral response resulting from a combination of different energy band gaps. This in turn implies that the device should have a relatively lower dependence on outdoor spectral content, which depends on a number of factors such as year time, location, day time and material composition in the atmosphere.

The availability of outdoor spectral data, which in most cases is not available, allows for the evaluation of the outdoor response of the CIS technology as the spectrum shifts during the course of the day, during cloud/clear sky condition and seasons. This study reports on the effect of outdoor spectrum, which is different from the reference AM 1.5, on the CIS performance parameters.
