AIR CONDITIONING SYSTEMS WITH DESICCANT WHEEL FOR ITALIAN CLIMATES

Hybrid air conditioning systems based on chemical dehumidification are characterised by high energy efficiency and low environmental impact. They can result profitable if compared to traditional air conditioning systems and allow to obtain better indoor thermal comfort and air quality. In this paper, different hybrid air conditioning system configurations with desiccant wheel are examined; later, a first evaluation of operating costs is carried on, for Italian climates. For this purpose, a commercial computer program, DesiCalc TM , has been employed: from the European file known as TRY, hourly climatic data have been derived and adequately processed. For retail store application, for four Italian sites, maximum saving of about 22% has been obtained, while for theatre obtainable saving is greater and has been evaluated between 23% and 38%. For both the applications, the required comprehensive electric power is reduced (up to about 55%), and also the hours during which the system does not well control indoor relative humidity are strongly reduced.

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