General solar cells use a semiconductor (silicon) that generates electricity when it is irradiated by sunlight. The AGC Group supplies products and develops technologies for use in both crystal silicon solar cells, which are now mainstream products, and thin film silicon solar cells, which are expected to become as popular as next-generation solar cells.

AGC Group Boasts the No. 1 Share of the World Market

Solite,
photovoltaic cover glass

Cover glass is used to protect the surface of crystal silicon solar cells. It efficiently transmits light, which in turn improves the power generation efficiency of solar cells. The AGC Group boasts the largest share of the global photovoltaic cover glass market with high optical transmittance glass, developed by AGC Flat Glass North America. By the adoption of unique technologies developed for surface shape design and antireflection (AR), the glass helps increase the light transmission to solar cells, in particular for light of specific wavelengths that can be easily converted to energy.

Used on the curved surface of a solar car
(Osaka Sangyo University’s solar car OSU model S’)

ETFE films are fluorinated films used to protect the special silicon that functions as a photovoltaic layer on flexible solar cells. These films excel in light transmittance and weather resistance and are expected to be widely used as material for next-generation solar cells. Flexible solar cells, as their name implies, can be flexibly installed, and some can be even carried in a bag. In the future, these cells are expected to be used as power generation devices for notebook PCs and cell phones.

Improving Power Generation Efficiency of Thin Film Silicon Solar Cells

Magnified photo of the Type HU TCO film

TCO films function as conductors to bring out electric energy. They are very important omponent which influence solar power generation efficiency. The films must meet the following conditions: first, they must be able to conduct electricity; second, they must be transparent; and third, they must be able to efficiently scatter light by means of their surface concavoconvex texture, to conduct more light into the photovoltaic layer for higher power generation efficiency. The AGC Group embarked on the development of TCO films in 1985 and succeeded in developing the Type U TCO film, now regarded as the world’s standard for TCO films, in the latter half of the 1980s. Furthermore, in December 2007, the Group unveiled the Type HU TCO film, a next-generation TCO film that can scatter 90% of incoming sunlight and conduct the light more efficiently into the photovoltaic layer.

Voices of Researchers
Making Persistent Efforts to Develop TCO Films

Naoki Taneda
Principal Researcher, Research Center

Despite the long-held belief that the solar cell market would grow in the future, we were virtually forced to abandon the development of TCO films on several occasions. Nevertheless, researchers at the Research Center, including myself, persisted engaging in developmental efforts, greatly supported by those in the relevant business divisions who believed in the growth of the solar cell market. Now that the market has finally taken off, all those engaged in the solar cell business, including those at the Research Center and in the relevant business divisions are all very excited. At the same time, however, competition in the market is intensifying and the market situation is ever changing. In the face of these circumstances, we would like to achieve success without missing any chances along the way.

Mika Kambe
Research Center

I have been continuing my research into solar cells since I was a university student. Following the downsizing of the department in charge of solar cell research and development, I had to suspend my research into solar cells for some time, but subsequently I was able to resume the research, for which I feel very fortunate. I am engaged in verifying the performance of TCO films used in solar cells. The AGC Group verifies the potential of TCO films, as a component of solar cells, in future technological development, a practice which I believe greatly strengthens the Group. Because of this, we are able to quickly provide customers with well-proven technologies.

Fuel cells generate electrical energy through the chemical reaction of hydrogen and oxygen, without releasing any byproducts other than water. The practical use of these cells as highly efficient and clear power generation devices for automobiles is therefore urgently required. Between the hydrogen and the oxygen supplies, a membrane known as a membrane-electrode assembly (MEA) is installed to enable ion exchange and electrical energy generation. When used in automobiles, these cells are operated under severe conditions (temperatures of 100ºC or higher and low humidity) and thus, the performance of fuel cells largely depends on the durability of MEAs.
The AGC Group has been promoting the development and practical use of MEAs as a core component of polymer electrolyte fuel cells. These cells can be made smaller and lighter and are expected to be applied to automobiles and portable devices as well. Using the technology it accumulated in the development of fluoropolymer ion-exchange membranes, the AGC Group has developed a highly durable MEA, which is the first fluorine-based MEA that can be continuously operated for 4,000 hours or longer at temperatures of 100ºC or higher, and the MEA is expected to be put into practical use ahead of other MEA products.

Membrane-electrode assembly (MEA) for fuel cells

Power generation by a fuel cell