Thin-Film And Crystalline Photovoltaic Modules – Outdoor Performance And Economic Estimation

Abstract

Thin film photovoltaic (PV) technologies were quite popular in 2005-2010 due to relatively low modules costs and low need in silicon or other materials. Amorphous silicon (a-Si) thin films are well known as PV active material with wider light absorption bandgap than for crystalline silicon which allows better module operation in case of diffuse radiation. Low PV energy conversion efficiency (7-11% against 16-19% for crystalline) is a main drawback of such modules. CuInGaSe2 (CIGS) thin films have no such features for absorption bandgap, but have large efficiency (13-14% for PV module and 20,4% for laboratory scale cell). It is also known, that thin film modules have much lower temperature power coefficient, which makes their operation more reliable at hot weather. Nowadays fast progress in crystalline silicon PV technologies led to lower cost for crystalline modules and made thin film technologies less competitive. In Joint Institute for High Temperatures comparative field tests of several thin film and crystalline modules were conducted in 2015-16, using small autonomous power units (PV module, charge controller, small accumulator for charge controller feed and resistive load) as a test bed. Specific energy production for each module throughout different months and the whole test period (10.2015-10.2016) was used as a main criteria for comparison. Economic efficiency (energy production to capital costs ratio for each module type) was also estimated.