AIST and Nippon Sheet Glass to Develop Solar Heat

AIST and Nippon Sheet Glass to Develop Solar Heat-Controlling Glass

The National Institute of Advanced Industrial Science and Technology (AIST), an independent administrative institution and Japan’s largest public research organization, has signed a collaborative R&D agreement with the Nippon Sheet Glass (NSG) on the development of solar heat energy controlling glass, aiming at commercialization within three years.

The target glass automatically controls the transmission of solar thermal energy, to achieve energy saving by deterring entry of solar heat into the room in summer, and by admitting solar radiation to the interior in winter, according to AIST.

Up to now, a variety of functional glasses have been available for windowpanes of housing, such as double insulating glass, low-E glass, vacuum-insulated glass, and heat-ray cut-off glass, contributing to energy saving. While these glass types are effective for reducing the room cooler burden by shutting out solar radiation in summer, and for reducing the room heater burden by thermal insulation in winter, the transmission of solar radiation through them is fixed throughout a year, and no function has been available to change solar heat intake depending upon the seasonal changes and dwellers' needs, AIST explains.

The target of the present collaborative study is to provide a glass coated with film made of vanadium oxide or its derivative, of which optical property varies with ambient temperatures while keeping the transmission to visible light nearly constant, controlling the solar heat intake in response to environmental temperatures.

AIST has been engaged for over a decade in the development of the preparation process, upgrading the transmission to visible light, and augmentation of solar heat control efficiency. It has successfully prepared a sample improving the visible light transmission up to 60 percent, and controlling the transmission of solar heat from around 60 percent to 20 percent in response to changes in temperatures from 10 degrees Centigrade to 68 degrees Centigrade.

In order to meet requirements for mass production technology in preparation for future commercialization, the AIST-NSG joint research will be carried out by combining AIST's research achievements with NSG's production technology of functional glasses. The plan is to release to the market within three years solar heat energy controlling glass of size for housing windowpanes.

Published 06/24/2005