Marketplace

  • Ion Science Ltd Laboratory, Monitoring & Analytical
    Ion Science Ltd

    ION SCIENCE COMPLETES MOVE INTO NEW PURPOSE-BUILT £4.5 MILLION FACILITY

    Gas detection instrumentation specialist's ultra-modern plant is open and geared to meet ambitious global growth plans for advanced VOC monitors.

  • Jacopa Water
    Jacopa

    Prevention better than Cure

    The Pump Centre in conjunction with Scottish Water has staged a one-day conference on the theme of 'Improving Reliability in the Water Industry'. The aim being to explore the factors that impact on the reliability of water and wastewater plant and equipment.

  • Cirrus Research Training
    Cirrus Research

    Cirrus Research training expanded to include Environmental course

    Noise Monitoring specialists Cirrus Research have expanded their product training and CPD programmes, adding an environmental noise measurement workshop to the roster.

  • Aquabio Movers & Shakers
    Aquabio

    Water treatment company raises funds for Sustrans cycling/walking charity

    A water re-use company has turned kilometres into pounds and donated funds to a charity which encourages people to walk and cycle.

v ecohouse button

baxi button web

web mossborough spud field copy

Thursday, 21 January 2016 15:10

Self-cleaning windows energy efficient thanks to nano 'moth eyes'

Nature inspired nano-structures developed by a London university will mean smart windows can clean themselves, save energy and mimic moth eyes to cut glare.

self clean windows1Developed by UCL (University College London) with support from the Engineering and Physical Sciences Research Council (EPSRC), prototype samples confirm that the glass can deliver three key benefits:

· Self-cleaning: The window is ultra-resistant to water, so rain hitting the outside forms spherical droplets that roll easily over the surface – picking up dirt, dust and other contaminants and carrying them away. This is due to the pencil-like, conical design of nanostructures engraved onto the glass, trapping air and ensuring only a tiny amount of water comes into contact with the surface. This is different from normal glass, where raindrops cling to the surface, slide down more slowly and leave marks behind.

· Energy-saving: The glass is coated with a very thin (5-10 nanometre) film of vanadium dioxide which during cold periods stops thermal radiation escaping and so prevents heat loss; during hot periods it prevents infrared radiation from the sun entering the building. Vanadium dioxide is a cheap and abundant material, combining with the thinness of the coating to offer real cost and sustainability advantages over silver/gold-based and other coatings used by current energy-saving windows.

· Anti-glare: The design of the nanostructures also gives the windows the same anti-reflective properties found in the eyes of moths and other creatures that have evolved to hide from predators. It cuts the amount of light reflected internally in a room to less than 5 per cent – compared with the 20-30 per cent achieved by other prototype vanadium dioxide coated, energy-saving windows – with this reduction in 'glare' providing a big boost to occupant comfort.

"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," said Dr Ioannis Papakonstantinou of UCL.

self cleaning windows3The UCL team calculate that the windows could result in a reduction in heating bills of up to 40 per cent, with the precise amount in any particular case depending on the exact latitude of the building where they are incorporated. Windows made of the ground-breaking glass could be especially well-suited to use in high-rise office buildings.

Dr Ioannis Papakonstantinou of UCL, project leader, explains: "It's currently estimated that, because of the obvious difficulties involved, the cost of cleaning a skyscraper's windows in its first 5 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."

Discussions are now under way with UK glass manufacturers with a view to driving this new window concept towards commercialisation. The key is to develop ways of scaling up the nano-manufacturing methods that the UCL team have specially developed to produce the glass, as well as scaling up the vanadium dioxide coating process.

Smart windows could begin to reach the market within around 3-5 years, depending on the team's success in securing industrial interest.

Dr Papakonstantinou says: "We also hope to develop a 'smart' film that incorporates our nanostructures and can easily be added to conventional domestic, office, factory and other windows on a DIY basis to deliver the triple benefit of lower energy use, less light reflection and self-cleaning, without significantly affecting aesthetics."

Professor Philip Nelson, Chief Executive of EPSRC 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."

A 5-year European Research Council (ERC) starting grant (IntelGlazing) has been awarded to fabricate smart windows on a large scale and test them under realistic, outdoor environmental conditions.

LINKS
Biologically Inspired Nanostructures for Smart Windows
Photonics Innovations Lab, UCL
UK - Housing Energy factfile