Strategies for exploiting climate potential through ventilative cooling in a renovated historic market

Nearly all retail locations use ventilation and cooling systems to ensure adequate air exchange for health reasons and indoor comfort temperatures. These systems can run for over 2,000 hours per year and we expect that average operating hours will continue to rise across Europe because of the continued trend towards longer opening hours and increased number of opening days. Shopping malls often enclose large open spaces and atria with high solar and internal gains that can drive ventilative cooling. This study presents the methodology applied to a historical market located in Valladolid (Spain) for the assessment of the ventilative cooling potential and the definition of a ventilative cooling strategy. The climate suitability and potential was evaluated based on the building internal gains rate and the considered ventilation strategies options (e.g. night cooling, daytime direct ventilation). Significant performance indicators were defined for each considered ventilation strategy. Once we determined the climate suitability, we defined a ventilative cooling strategy, that exploits openings in the façade and in the skylight to promote stack effect ventilation. We sized openings area and location on the façade, taking into account design constraints, and we assessed their performances by dynamic simulations in Trnsys coupled with Trnflow airflow network. Results show the potential cooling load reduction, with the achievement of acceptable thermal comfort due to the ventilative cooling in the shopping mall. The proposed methodology can support the design decision process towards cost effective low energy shopping malls.