NANOCOOL

Air-conditioning is a rapidly growing electrical end-use in EU. A/C systems reduce temperature of the ambient air while removing humidity. However such combined air conditioning/dehumidification is generally inefficient. A promising approach is represented by Hybrid Liquid Desiccant (HLD) systems, where the latent load is removed by a liquid desiccant dehumidifier, while the sensible load is removed by a conventional vapor compression air cooler. The heat required for regeneration of the liquid desiccants needs however to be provided by outer sources like natural gas or solar collectors. Furthermore almost all metal alloys are corroded by the most effective liquid desiccants. HLD systems are therefore not penetrating the market. Our goal was to develop an innovative HLD system in the range 100-200 kW, where waste heat from the condenser is used for regeneration of the desiccants. The energy demand by this process is 55% of the conventional technique. In cases of severe humid environments, like swimming pools, or kitchens, the energy savings can achieve easily levels of 65%-70%. Several innovative components have been developed, namely: Two multifunctional heat exchangers with high corrosion resistance for either water vapour absorption from the air flow or desiccant regeneration; Development of a liquid-liquid heat exchanger with high corrosion resistance for desiccant regeneration process pre-heat (liquid-liquid desiccant). Based on the promising results of the FP7 Thermonano project, thermally conductive polymer nano-composites were considered as material for these components and shaped into innovative engineered heat exchange surface. The partners foresee an initial market worth up to 180 MEuro by 2020, generating/maintaining 4000 job opportunities for skilled operators and installers. The partners expect that the intended HVAC solution will allow cumulative savings on energy bill of at least 60 MEuro with a pay-back time below 2 years in case of 50% use.