Polymer solar cells have unique features such as low weight, slim outline, robustness against breakage and excellent adaptability of size, shape and curvature to the actual application. These features open, not only for cost- and energy effective application of the cell, but also for aesthetic solutions. The potential for reaching low production cost at high production volumes is significant, as the polymer solar cell is produced in a roll-to-roll process. The potential for low-cost processing relates not only to the solar cell itself but also to the further processing of the solar cells into more refined products. Such refined products might be self-powered electronic devices designed for easy integration in the customer’s production or solar-powered products for the end-user. A three-phased project with the objective to industrialize DTU’s basic polymer solar cell technology was started in the summer of 2009. The technology comprises a specific design of the polymer solar cell and a corresponding roll-to-roll manufacturing process. This basic technology is referred to as ProcessOne in the open literature. The present report relates to the project’s phase 1.The key tasks in phase 1 are to stream-line DTU’s tech-nology for the industrial utilization, to demonstrate production according to this stream-lined technology at Mekoprint A/S and finally to fertilize the market for polymer solar cells by demonstrating their use in appli-cations that harmonize with their present maturity level. The main focus in the stream-lining of DTU’s technology has been to demonstrate a convincing rate of re-duction for the production cost, and thereby make a competitive price plausible. This has been materialized as a learning curve showing that the polymer technology presently develops considerably faster than the silicon technology.The polymer solar cells will, under the assumption that both technologies follow a projec-tion of the learning curve, gain a cost-leading position within a reasonable time. A production cost of 5 €/Wp has already been demonstrated in DTU’s pilot plant, and a road map for the further decrease to 1 €/Wp is drawn. This target is expected to be reached in 2013 in the ongoing phase 2 of the project. Another activity essential for the industrialization has been the launch of specialized materials, equipment and services required for the processing of DTU’s polymer solar cells. Relevant products and services are made available for sale on DTU’s homepage, www.energyconversion.dtu.dk. A production line for polymer solar cells has been established at Mekoprint. For this a retrofit solution was chosen where the core of an existing screen-printing line was dismantled and fitted to a slot-die printing head manufactured in DTU’s workshop. The line was at the same time adjusted and updated to handle the new production. The very first solar cells produced on this line appeared in July 2010. The line has subse-quently been upgraded on a running basis, and Mekoprint’s operators have been trained. The technology transfer is continued in the project’s phase 2, where the goal is that Mekoprint fully masters both the pro-duction process and the production line. During the course of the project several applications for polymer solar cells have been investigated from a technical -, a design –, and a market point of view. Faktor 3 has sketched and visualized a range of ideas. The ideas are communicated to a broader audience by means of a brochure. An on-line version of the bro-chure and a computer tool developed for guiding the designer through the process of dimensioning the electronic system comprising a polymer solar cell, a battery and the electronic function to be powered, are available on Faktor 3’s homepage, www.faktor-3.dk. Small LED torches have served as a case for gaining experiences with development and production of so-lar powered products. A range of conceptual lamps have been evaluated, and two lamps have been pro-duced in large series and demonstrated in public. Some hundred lamps targeted at school children in non-electrified areas in 3rd world countries were produced and distributed to target users in Asia, Africa and South America in collaboration with the Strømme Foundation (NO). The feedback received was highly posi-tive and proves the necessity for low-cost, off-grid lightening to replace the presently used kerosene lamps. A small credit-card sized lamp was produced in a series of 10.000 units in order to test the production se-tup’s ability to handle large series. Several thousands of the lamps were handed out at an international conference for printed electronics, (LOPE-C, 2011). The response from this audience, who is well qualified to judge the news value of lamp’s, has also been highly positive. Based upon the positive demonstration events, two products are launched for sale on Mekoprint’s home-page; a laser-pointer and a LED flashlight, see www.mekoprint.com. Both Mekoprint and Faktor 3 have more products in their pipelines.
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Department of Energy Conversion and Storage, Technical University of Denmark, 2012