Search

In this paper, daylighting and thermal analysis are carried out in synergy to ensure the best overall performance of perforated solar screens (PSS) used on fully glazed offices facing towards South, East, West and North, placed in Seville. The study has been conceived by applying multiple orthogonal arrays to account oriented transverse comparisons of several PSS design variables, with respect to their impact on the Daylight Availability (DAv) and the annual energy demand (lighting plus cooling and heating). Daylighting and irradiation calculations are carried out with DIVA-for-Grasshopper. The irradiation simulations are needed for simplifying the PSS complex geometries in order to perform thermal calculations with EnergyPlus. The results revealed that the use of PSS on façades is effective for enhancing DAv at the four orientations, in terms of the actual fully daylit area and the useful daylight illuminances. In comparison with fully and partly glazed façades, PSS increased the electrical lighting use but they considerably decreased the cooling energy use. Since lighting resulted lower and less influencing than cooling, PSS effectively reduced the total annual energy consumption. Therefore, optimizing daylighting through PSS can lead to low energy projects. [ABSTRACT FROM AUTHOR]

On fully-glazed building façades perforated solar screens (PSS) are often used as an outer skin in order to reduce energy consumption and to solve issues such as visual appearance. However, not only must PSS control solar radiation but they must also provide adequate daylight levels, thus requiring a balanced solution. Currently, daylighting simulation software enables us to perform efficient daylight analysis of spaces with PSS. Notwithstanding this, current energy simulation software such as EnergyPlus cannot deal well with such geometry directly, making the thermal evaluation of PSS an infeasible task. This paper presents a methodology for achieving an integrated analysis of daylighting and energy consumption of spaces with PSS during the design stage. Such methodology provides daylight analysis through DIVA, and thermal analysis through EnergyPlus via DIVA/Grasshopper/Archsim. The aim is to optimise the dual performance of a balanced PSS solution through controlling its perforation percentage, matrix and shape, by using the orthogonal arrays (DOA) statistical method. DOA method is efficient in reducing the number of simulations derived from the combination of the aforementioned variables, and in identifying the optimal PSS configuration. In comparison to a non-optimised façade located in Seville, Spain, the predicted optimal PSS achieved a 50% increase in the actual daylit area and a 55% reduction in the total energy demand. [ABSTRACT FROM AUTHOR]