'Smart' window that tints, powers itself

Scientists from the Nanyang Technological University here have developed a "smart" window which can darken or brighten without the need for an external power source.

This unique self-tinting window requires zero electricity to operate and is also a rechargeable battery.

The window's stored energy can be used for other purposes, such as to light up low-powered electronics like a light emitting diode.

Currently, the window solutions in the market are either using permanent tinting which cannot brighten at night or are windows that can change its light transmission properties only with an external power source.

The "smart" window, however, can be turned into a cool blue tint in bright daylight, cutting light penetration by about half, and then reverts back to clear glass at night or as required.

"Our new smart electrochromic window is bi-functional; it is also a transparent battery. It charges up and turns blue when there is oxygen present in the electrolyte - in other words, it breathes," explained lead researcher professor Sun Xiaowei.

Such an innovative technology can adjust the amount of sunlight coming into buildings in the day which promises significant savings on cooling and lighting costs.

"Buildings owners and even common households can reap energy savings right from the outset and over the long term. Developers who are looking at constructing environmentally-friendly green buildings will find our technology attractive for their building plans," Sun explained.

The study was published in the journal Nature Communications.