Panasonic Corporation (Osaka, Japan) has achieved a 24.7% cell efficiency with its HIT solar photovoltaic (PV) technology at the research level, using a 98 micrometer-thick, 102 square centimeter cell.

This is the highest efficiency yet reached for a monocrystalline silicon PV cell under standard sunlight levels at a size greater than 100 square centimeters. The company credits a new cell production technology which enables it to reduce recombination losses as well as optical and electrical improvements for the higher efficiency.

The new record exceeds the previous efficiency record of 23.9% for HIT PV cells by 0.8%, and is 0.5% greater than the previous record for monocrystalline PV cells greater than 100 square centimeters. Panasonic notes that achieving this efficiency at a thickness of 98 micrometers may also allow it to reduce costs.

New technology allows for higher quality a-Si

Panasonic's HIT technology is based on the lamination of amorphous silicon layers onto the surface of monocrystalline substrates, which is the layer that generates power.

The company's new technology allows it to form an amorphous silicon (a-Si) layer of higher quality on monocrystalline silicon substrates, while limiting damage to the surface of the substrate. Due to the resulting reduction in recombination losses, the open voltage has been improved from 0.748 volts to 0.750 volts.

Optical, electrical improvements

Panasonic further reports reducing light absorption losses in the transparent conductive coating and the amorphous silicon layer.

Finally, the company has decreased shading loss by reducing the surface area of the grid electrode on the cell surface, as well as improving the grid electrode by reducing resistive losses.

2013-02-12 | Courtesy: Panasonic | solarserver.com © Heindl Server GmbH

Our editorial selection of breaking solar news is published at:
www.solarserver.com/solar-magazine/solar-news/top-solar-news.html