In order to reach the objective of low-cost, large area organic photovoltaic systems, we build up a knowledge base concerning the influence of process conditions on the performance of polymer solar cells. A large area solar cell module, with roll-to-roll coated PEDOT:PSS and photoactive layers (based on P3HT:[C60]PCBM blend) on a flexible substrate, has been demonstrated. Both the PEDOT:PSS and photoactive layer were deposited by slot die coating. A non-chlorinated solvent was used for the deposition of the photoactive blend. The flexible solar cell module illustrated a power conversion efficiency of 0.7% under AM 1.5 conditions. Methods to further improve the technological process are proposed. (C) 2010 Elsevier B.V. All rights reserved.