Integration of an innovative dual day-night technique for air conditioning of public spaces

Abstract

The citizen has lost his place in the streets. Also, streets have become hostile and unlivable due to climate change and unsustainable urbanization. CartujaQanat project was born to mitigate the problems discussed. CartujaQanat is an innovative urban transformation project through which the use of the street as a social activator will be promoted, improving it and involving the city's entire ecosystem in this transformation. This new model of urban governance will serve as a facilitator for introducing these models in their expansion throughout the city to gradually change the appearance and functionality of the street concept and its future evolution in the next 15 years. So, this paper shows a set of solution for climatic control of outdoor conditions for two open public spaces in Seville. These techniques guarantee thermal comfort by the implementation of passive and adaptive bioclimatic solutions. The natural element of thermal dissipation is water, which will allow the air conditioning of spaces by cooling the air. One of the keys to the project is the cooling of water using the natural technique "falling-film". The water is driven from accumulation volumes by fan nozzles on the photovoltaic panels arranged on the installation roof, forming a falling film on them. This innovative technique allows the water to be cooled through a convective-radiant effect during the night thanks to the low temperature of the sky, obtaining promising results of thermal dissipation, whose dissipation heat varies depending on the flow width and length of the film travel. The duality of the system allows the cooling of water at night and the production of electricity during the day in order to guarantee a zero-energy balance in the installation.