Many people spend long periods of time inside commercial and public buildings where only 10-15% of the air could be fresh, with the remaining part being put back into circulation, often for efficiency reasons. Unfortunately, exposure to low quality air can lead to a greater presence of allergies and even respiratory diseases. The NANO-HVAC (Novel nano-enabled energy efficient and safe HVAC ducts and systems contributing to a healthier indoor environment) project used a dual approach to improve conditions in buildings.

The first approach involved developing safe, highly insulating HVAC ducts that minimize heat and cooling loss. Extremely thin, safe and cost-effective duct insulation linings have been achieved using aeroclay-based insulating foams that can be applied automatically during manufacture. These technologies are able to achieve a saving of 50% in energy losses and a reduction of 45% in the cost of the duct compared to conventional insulated ducts.

The second approach involved removing pathogens and allergens during operation and maintenance in order to reduce microbial growth. Project partners developed an antimicrobial, fungicidal and non-allergenic self-adhesive spray-on coating based on titanium oxide nanoparticles. This can be applied to HVAC filters during manufacture or while in situ. In addition, the use of a low-energy ultraviolet light emitting diode system will increase the energy consumption of HVAC systems by up to 1%.

Researchers also developed an injectable liquid polymer matrix, which includes polyamine-derived epoxy resins with cross-linking catalysts, which contained antimicrobial silver oxide nanoparticles. This was used for on-site maintenance of the air ducts, where the liquid polymer creates a coating that covers the surface, blocking dirt, debris and microorganisms and thus generating the inner layer of the duct.

NANO-HVAC has successfully used antimicrobial and non-allergenic solutions to improve the indoor environment. thus improving people’s health and well-being, and producing significant energy savings. It will also help make Europe a leader in cutting-edge HVAC systems.