With Germany's feed-in-tariff (FIT) slash in the third quarter of 2010, and strong demand from other solar markets buoying upstream prices, the internal rate of return (IRR) of installing a crystalline silicon (c-Si) solar system has dropped to 6-8% versus 10% for thin-film silicon systems.

With some thin-film system installers offering modules capable of generating 130-140W and priced at 1.1-1.2 euro/W (US$1.53-1.67), and under the same financing conditions, it is the first time thin-film systems have offered a higher investment return.

Since IRR is the main criteria when considering solar system installation, thin-film systems are expected to generate more interest in Germany, which has also served to stabilize thin-film module quotes thus far.

Industry sources indicated that based on the mentioned electricity generating numbers, the systems should be based on tandem-junction thin-film technology and not all thin-film module companies are capable of such quotes.