AFP/AFP/File - Pedestrians walk through the financial district of Shanghai on October 16, 2013
Scientists in China said Thursday they had designed a
"smart" window that can both save and generate energy, and may
ultimately reduce heating and cooling costs for buildings.
This has sparked a quest for "smart" windows that can adapt to weather conditions outside.
Today's smart windows are limited to regulating light and heat from the sun, allowing a lot of potential energy to escape, study co-author Yanfeng Gao of the Chinese Academy of Sciences told AFP.
"The main innovation of this work is that it developed a concept smart window device for simultaneous generation and saving of energy."
Engineers have long battled to incorporate energy-generating solar cells into window panes without affecting their transparency.
Gao's team discovered that a material called vanadium oxide (VO2) can be used as a transparent coating to regulate infrared radiation from the Sun.
VO2 changes its properties based on temperature. Below a certain level it is insulating and lets through infrared light, while at another temperature it becomes reflective.
A window in which VO2 was used could regulate the amount of Sun energy entering a building, but also scatter light to solar cells the team had placed around their glass panels, where it was used to generate energy with which to light a lamp, for example.
"This smart window combines energy-saving and generation in one device, and offers potential to intelligently regulate and utilise solar radiation in an efficient manner," the study authors wrote in the journal Nature Scientific Reports.