Amazing Breakthrough in Solar Energy

Nanosolar was founded in 2002 to make solar power inexpensive through Silicon Valley style technology innovation. Since 2004, we have focused on executing a plan of reinventing CIGS – the most efficient and stable photovoltaic thin-film semiconductor – for superior cost and capital efficiency, targeting a cost/performance level not considered achievable by many experienced experts and institutions.

After five years of intense development and perseverance, we have delivered on our cost objectives, attained IEC 61646 & 61730 product certification, and are now in serial production, with our production run rate presently set at a sub-capacity level consistent with our market-introduction business objectives.

In order to realize the extent of this advance in cost efficiency, we addressed a host of fundamental science and engineering challenges. We developed a completely new semiconductor synthesis process with novel nanostructured materials, novel substrate and cell-architecture technologies, and new tooling designs to implement all of this as part of a new continuous-processing manufacturing framework.

Our team has developed an ultra-low-cost solar cell based on five principal bodies of technological innovation:

1. the use of a highly conductive, low-cost aluminum foil as the substrate and bottom electrode of the cell;
2. a CIGS ink with loaded-in stochiometric ratio and a high-yield high-throughput printing process to form an electronic-grade CIGS semiconductor;
3. a novel Metal-Wrap-Through (MWT) back-contact design based on high-throughput foil lamination;
4. a thin/printed transparent top electrode; and
5. redesign and development of materials deposition processes that work with and leverage the superior steady-state uniformity and other characteristics inherent in roll-to-roll processing.

These five bodies of innovation address each component of a solar cell and its cost and capital efficiency, delivering the definitive improvement necessary to obtain an ultra-low-cost product:

Innovation (1) delivers low materials cost, a low-cost substrate, and a low-cost bottom electrode (which otherwise would have to be created through an expensive thin film).

Innovations (2+5) deliver a low-cost absorber/semiconductor with high material utilization and supreme capital efficiency.

Innovation (3+4) enables a low-cost top electrode and simple, fast, robust cell interconnects. The combination of a highly conductive aluminum substrate with our MWT cell architecture results in cells capable of generating and carrying currents of 6-25 Amps, or 3-10x more than is cost efficient with state of-the-art thin-film solar cells today.

http://cache.rmartinr.com/NanosolarCellWhitePaper.pdf