Numerical Assessment of Zebra-Stripes-Based Strategies in Buildings Energy Performance: A Case Study under Tropical Climate

Miguel Chen Austin,Dafni Mora,Paola Palacios,Katherine Rodríguez Maure,Kevin Araque

doi:10.3390/biomimetics7010014

Abstract

Urban growth has increased the risk of over-heating both in the microclimate and inside buildings, affecting thermal comfort and energy efficiency. That is why this research aims to evaluate the energy performance of buildings in terms of thermal comfort (operative temperature (OP) levels, satisfied hours of natural ventilation SHNV, thermal lag), and energy efficiency (roof heat gains and surface temperatures) in an urban area in Panama City, using superficial-heat-dissipation biomimetic strategies. Two case studies, a base case and a proposed case, were evaluated using the Designbuilder software through dynamic simulation. The proposed case is based on a combined biomimetic strategy; the reflective characteristics of the Saharan ant applied as a coating on the roofs through a segmented pattern such as the Zebra’s stripes (one section with coating, and another without). Results showed that the OP decreased from 8 to 10 °C for the entire urban zone throughout the year. A reduction of 3.13% corresponding to 8790 kWh per year was achieved for cooling energy consumption. A difference of 5 °C in external surface temperature was obtained, having a lower temperature in which the biomimetic strategy was applied. Besides, it was evidenced that a contrasted-reflectivity-stripes pitched roof performed better than a fully reflective roof. Thus, the functionality of Zebra stripes, together with the reflective characteristics of the Saharan ant, provide better performance for buildings’ thermal regulation and energy needs for cooling.

Highlights

In the last century, there has been a high growth of urban areas where deforestation of green areas was not considered, and materials were used in buildings with high thermal retention, soil occupation, and high levels of greenhouse gas emissions
The greenhouse effect is on the other hand; urban areas consume between 60% and 80% of the energy produced, which today has generated a high environmental and energy cost for the planet [1]
Such consequences are reflected in the effect of urban heat islands (UHI) in cities that cause high rates of heat and temperature in urban areas and affect people’s comfort both outside and inside buildings and in the high rates of energy consumption of a part of the buildings

Summary

Introduction

There has been a high growth of urban areas where deforestation of green areas was not considered, and materials were used in buildings with high thermal retention, soil occupation, and high levels of greenhouse gas emissions. The greenhouse effect is on the other hand; urban areas consume between 60% and 80% of the energy produced, which today has generated a high environmental and energy cost for the planet [1]. Such consequences are reflected in the effect of urban heat islands (UHI) in cities that cause high rates of heat and temperature in urban areas and affect people’s comfort both outside and inside buildings and in the high rates of energy consumption of a part of the buildings. Measures have been taken regarding regulations to be able to seek options and strategies that allow greater comfort and low energy consumption in new constructions, such as the sustainable construction manual (RES), which represents the first steps in the search for new sustainable buildings with low energy consumption [4]

Objectives

Methods

Results

Discussion

Conclusion