Mitsubishi claims to have broken solar cell world record

Mitsubishi Electric yesterday claimed to have successfully the world' most efficient photovoltaic cells and pledged to have the new technology in mass production by 2010.

The company said it had developed a 150-millimeter square multi-crystalline silicon solar cell boasting a photoelectric conversion efficiency rate of 18.6 per cent, an improvement of 0.6 per cent on the company's previous record.

Mitsubishi Electric President and CEO Setsuhiro Shimomura said that the new cells were also more efficient in shaded conditions, making them better suited for use on household roofs.

The new cell exploits a honeycomb textured structure to reduce light reflectivity on the surface of the cell and increase efficiency. Such honeycomb structures have long been touted by solar cell experts as a means of improving efficiency, but Mitsubishi claims to be the first to have developed a way of applying the technology to a mass production line through a new fabrication process combining laser patterning and wet etching.

The company claims to have also improved the cell's power generation efficiency through the use of a new shallow, lightly doped emitter that increases light gain.

The announcement came as the company also pledged to invest 7bn yen (£35m) as part of its plan to increase its annual solar cell and panel production more than threefold over the next four years to 500MW.