Date
08/25/2012
IBM's Materials Science team has partnered with Solar Frontier, TOK (Tokyo Ohka Kogyo), and DelSolar to develop an efficient and affordable PV cell made of abundant natural materials. So far, the tests of its CZTS (Cu2ZnSn[S,Se]4) thin-film devices have achieved a world-record PV solar-to-electric power conversion efficiency of 11.1%10% better than previous reports for this class of semiconductor. It can be manufactured by simple ink-based techniques such as printing or casting. The CZTS PV cells could potentially yield up to 500 GW/yeargetting closer to the TW levels of renewable electricity the planet needs. The focus of IBM's joint-development team remains to further increase this device efficiency and transfer the technology to environmentally-friendly, high-throughput industrial manufacturing. Other thin-film chalcogenide materials used in PV cells, such as CIGS (Cu[In,Ga][SSe]2) and CdTe, have been developed to a performance level close to that of silicon, with inherently more scalable processing. They are directly deposited on large-area, low-cost substrates such as glass, metal or plastic foil. But while CIGS and CdTe are easy to integrate into buildings and consumer products, their compounds contain rare and expensive elements that increase cost and limit their manufacturing levels to < 100 GW per year. (Worldwide continuous electricity consumption is 15 TW). The hope is that within several years, this new CZTS class of photovoltaic materials will contribute to the wider availability of lower-cost solar electricity. IBM Solar Frontier TOK DelSolar More information about CZTS PV technology