Scientists have developed a new coating that can be applied to window glass that will change how sunlight passes through so as to save energy.
The US Department of Energy’s Lawrence Berkeley National Laboratory is behind the research, which it believes is “raising the IQ of smart windows”, which means a thin coating of nanocrystals are embedded in the glass that modify the rays of sunlight.
This new coating allows for “selective control” over visible light and heat-producing near-infrared (NIR) light, meaning the windows can adapt to different climates and provide the best energy saving for the customer.
“In the US, we spend about a quarter of our total energy on lighting, heating and cooling our buildings,” explains Delia Milliron, a chemist at Berkeley Lab’s Molecular Foundry who is involved in the new research. “When used as a window coating, our new material can have a major impact on building energy efficiency.”
Milliron and her research group (Guillermo Garcia, Jaume Gazquez, and Anna Llordés) have done extensive work on smart-window technology that blocks NIR without blocking visible light. This allows natural lighting indoors but without any “unwanted thermal gain”, which reduces the house’s need for air conditioning or artificial lighting and can lead to significant energy savings for the household.
At the same time, the window can then be changed to “dark mode”, which will block light and hear, and a standard, fully transparent mode.