A new solar cell technology can be used in self-powered smart windows that could help save energy costs, scientists have said.
Smart windows equipped with controllable glazing can augment lighting, cooling and heating systems by varying their tint, saving up to 40 per cent in an average building’s energy costs. But these conventional smart windows require power for operation, so they are relatively complicated to install in existing buildings.
The new self-powered version promises to be inexpensive and easy to apply to existing windows, the researchers said. This system features solar cells that selectively absorb near-ultraviolet (near-UV) light, so the new windows are completely self-powered.
The smart window controls the transmission of visible light and infrared heat into the building, while the new type of solar cell uses near-UV light to power the system.
In the paper published in Nature Energy, the researchers described how they used organic semiconductors – contorted hexabenzocoronene (cHBC) derivatives – for constructing the solar cells.
The researchers chose the material because its chemical structure could be modified to absorb a narrow range of wavelengths — in this case, near-UV light.
The researchers explained that the near-UV solar cell technology can also power internet-of-things sensors and other low-power consumer products.