The organic solar cell -- dubbed the Organic P-N Junction -- is a sandwich structure containing two metal layers mounted on a plastic substrate, with each layer topped with nano structured plastic polymers serving as insulators, according to Chen Fang-chung, an assistant professor in NCTU's Department of Photonics.

The Organic P-N Junction has a power conversion efficiency of 5.2 percent, the highest in the world to date in terms of organic solar cell power, Chen said.

Due to rising oil prices, new energy sources are urgently needed, Chen said, adding that the Organic P-N Junction is a promising candidate to become a low cost, high-throughput and flexible energy source because it is flexible, lightweight and easy to carry.

The Organic P-N Junction, which is slightly larger than a business card, can be used by mobile phone or notebook PC users as a portable charger, Chen said, adding that it can also be used by campers or mountain climbers as a flexible energy source.

Chen estimated that the pioneering product could start being mass produced in three to five years, generating a market of around US$1 billion initially.