Technology: Smart glass reacts to the weather

Professor of inorganic and materials chemistry, Ivan Parkin, and Troy Manning, both of the chemistry department at University College London, developed the intelligent window coating as part of Mr Manning's PhD studies.

The thin film is made out of a material called vanadium dioxide, and it undergoes a change depending on the weather outside.

On cold days the "thermochromic coating" allows all sunlight in, while on hot days, once the outside temperature reaches a certain level, the film begins acting as a filter, blocking infrared rays, which are responsible for generating heat.

Parkin told CNN the film could be manufactured to have a predetermined heat threshold of between zero and 70 C, although it would be most useful if it were set to work at 25 C.

Its altering properties meant it could act as a replacement or partial replacement for air-conditioning systems, reducing electricity costs.

"It acts as a semi-conductor when the temperature is below a certain level, and is transparent. When the temperature rises, it turns into a metal, and becomes reflective," Parkin said.

He has had a huge amount of interest about turning the idea into a commercial reality, particularly from architects, but also from space agency NASA and greenhouse manufacturers.