Cooling energy savings with dry cooler equipped plants in office buildings

The cooling energy requirements are a key issue for office buildings in warm climates, but they have become considerable also in temperate climates, ‘cause the growing level of buildings thermal insulation. This aspect is more critical in office blocks than in residential buildings, due to the higher value of thermal energy supplied by internal loads. Office buildings are usually equipped with cooling systems in order to guarantee thermal comfort conditions for the office workers. The aim of this work is the evaluation of energy saving reachable in office blocks cooling requirements, using a water indirect free cooling operating procedure for the plant. It is assumed that the HVAC plant is equipped with dry-coolers that work as coolers of the refrigeration equipment condensers or just as coolers of the water to be supplied to fan coils. As the more solar radiation there is, the more cooling power is needed, dry-coolers, equipped with on-board photovoltaic panels, have been considered. The cooling loads of the office block have been evaluated through Energy Plus hourly time-step simulations for different climate conditions. Finally, electrical consumption of dry-c and energy produced by PV panels in different climates and with different tilts have been evaluated and compared.