Low cost and flexible solar cells for developing countries

Swiss Coordinator : Ayodhya Nath Tiwari, Thin Film Physics Group, ETH Zurich
Main Foreign partner : Satyendra Kumar Indian Institute of Technology, Kanpur
Cooperation with : India
Disciplines : Solar Energy, Condensed Matter Physics, Material Sciences

Abstract
Sustainable development in developing countries calls for effective clean solutions for the in-creasing energy demands. India with its population spread over a vast landscape is endowed with abundant sunshine over a large part of the year. Solar cell technologies have very high potential and important role in providing solar-electricity power for a variety of applications. Silicon solar cell technologies are quite mature and solar modules are commercially available. However, the spread of these technologies in the developing world has been marred due to their high costs. There is a crying need for developing alternative solar cell technologies that are less energy intensive (low energy pay back period) and require moderate manufacturing technologies with low cost, even if the peak efficiencies are relatively low. Flexible and light-weight solar cells offer several advantages for portable source of power and for building integration.

ETH Zürich has achieved record efficiencies of 14.1% on flexible solar cells based on compound semiconductor thin films, and in collaboration with Solaronix SA, a small Swiss company, developed a potentially low cost deposition process for chalcopyrite thin film solar cells. Solaronix is actively pursuing the manufacturability of TiO2-based solar modules that can be potentially low cost. IIT Kanpur, India group has developed flexible light emitting devices based on organic materials. Efforts are now directed to develop organic solar cells with low cost processes and to develop transparent conducting oxide layers on plastic substrates for solar cells and organic light emitting devices. There is obviously a strong synergy between the IITK and ETHZ R&D work as some components and processes are common in these compound semiconductor and organic solar cells. More specific common issues are: substrates, contacts, interfaces, conversion efficiency and long term stability. Organic and TiO2 composite solar cells is an emerging field and experiences from relatively more advanced thin film flexible solar cell technology will help in identifying and solving key challenging problems and thereby enabling efficiency and stability improvement in low cost solar cells.

Present proposal is directed towards developing research capabilities in the area of low cost flexible solar cells and identifying the niche applications where lightweight and flexible solar cells can contribute to the developmental needs in Indian domain. In addition to the needs and market potential strategies will be defined for providing solutions based on solar electricity generated by flexible and lightweight solar cells.

Contact Addresses:

ETH Zurich
Dr. Ayodhya Nath Tiwari
Thin Film Physics Group
Laboratory for Solid State Physics
ETH Building-Technopark
Technoparkstr.1
CH-8005 Zurich, Switzerland
Tel: +41-44-4451474, Fax:+41-44-4451499
E-mail: tiwari@phys.ethz.ch, http://www.tfp.ethz.ch

IIT Kanpur
Prof. Satyendra Kumar
Department of Physics
Indian Institute of Technology Kanpur
KANPUR - 208 016
INDIA
Tel: +91-512-259 7654
Fax: 91-512-259 0914
E-mail: satyen@iitk.ac.in