New self-cleaning smart windows 'could cut heating bills by up to 40%'
Smart windows that clean themselves and cut heating bills by up to 40% have been developed by British scientists.
The windows are ultra-resistant to water, thanks to pencil-like microscopic structures engraved into the glass.
Water simply rolls off the panes in spherical droplets, picking up dirt, dust and other contaminants and carrying them away.
A super-thin coating of vanadium dioxide also prevents heat loss from the windows during cold periods. In hot weather, it also prevents infra-red radiation from the sun entering the building and raising the temperature.
Dr Ioannis Papakonstantinou, who leads the University College London team, said: "This is the first time that a nanostructure has been combined with a thermochromic coating.
"The bio-inspired nanostructure amplifies the thermochromics properties of the coating and the net result is a self-cleaning, highly performing smart window."
He added: "It's currently estimated that, because of the obvious difficulties involved, the cost of cleaning a skyscraper's windows in its first five years is the same as the original cost of installing them.
"Our glass could drastically cut this expenditure, quite apart from the appeal of lower energy bills and improved occupant productivity thanks to less glare. As the trend in architecture continues towards the inclusion of more glass, it's vital that windows are as low-maintenance as possible."
Talks are now under way with UK glass manufacturers with a view to commercialising the concept.
The first smart windows could reach the market in three to five years, depending on the level of industry support.
Professor Philip Nelson, chief executive of the Engineering and Physical Sciences Research Council (EPSRC) which contributed £100,000 to the research, said: "This project is an example of how investing in excellent research drives innovation to produce tangible benefits.
"In this case the new technique could deliver both energy savings and cost reductions."