A radiative cooling system applied to a typical Portuguese building was studied in order to minimize the electric consumption of a heat pump. The cooling system consists of an inertia tank which absorbs excess heat from the building, and dissipates it using a thermal photovoltaic panel. This is a 24h working system, during the day absorbs the excess heat, at night time the system forces the heat water to pass through the photovoltaic panel in order to cool down, using the radiative and convective natural effect. This system takes advantage of the sky nocturnal effect and the outside air.

This study was performed in TRNSYS, using a mathematical and a physical model developed for this analysis. The purpose is to evaluate the performance of the system in a typical Portuguese building exposed to the Mediterranean climate. The benefits of introducing this new passive system were evaluated in order to decrease energy consumption compared to a reversible heat pump.

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