New efficient windows

H&V News describes new developments in windows. As the article states, windows are acknowledged to be a key weak point in terms of the building’s energy use and improvements can have a major impact. It would be good to hear the views of the glass industry.

New technology set to improve the thermal efficiency of windows

After two and a half years of scientific research and technological development in polymer compounding and multi-layer extrusion techniques, a solution has been found to make windows more energy efficient.

The project partners – which included Eurofilms Extrusions, Wells Plastics, Hanita Coatings, Hermaos Del Pino Espinosa and the UK Materials Technology Research Institute (UK-MatRI), a Pera Technology company – identified a low-cost, organically-based, readily available multi-layer polymeric switchable reflective SHGC film coating.

The multi-layer film operates in the infra-red region giving control to the amount of heat radiated whilst retaining a constant level of visible light transmission.

The number of films in the multi-layer stack are minimised to ensure that the SolarGain technology is cost competitive and large areas of film can be controlled from one source.

The technology requires a small voltage to ‘switch’ the film and can be supplied as part of a window unit or retro-fitted onto existing windows.

Speaking about the project EuroFilms managing director Nick Smith said: “Buildings are a major drain on European energy resources. They represent over 40 per cent of energy consumption in the EU, which is equivalent to over 1,800 million tonnes of CO2 emissions. If Europe is to meet its Kyoto Protocol commitments, improving the energy efficiency of buildings is a priority objective.

“A building’s windows – whilst attractive, desirable and essential to the comfort of the occupiers – are also acknowledged to be a key weak point in terms of the building’s energy use. Due to their inferior insulating properties, they lose heat during the winter months. Thanks to excessive heat gain from the sun during the summer months, they also require expensive energy-intensive air conditioning to cool the building down.

“With such window-related losses representing 10 per cent of a building’s energy consumption – 4 per cent of Europe’s total energy use – it’s clearly a serious problem, and one that the SolarGain project has taken huge steps forward in addressing.”