Exploring the energy and CO2 emissions implications of climate-responsive design strategies applied to residential dwellings in Latin America

The United Nations Habitat Assembly addresses the problems of urban growth and recognizes that cities are the main cause of climate change. Globally, cities account for ~75% of global energy consumption and 70% of global greenhouse gas emissions. Almost 10% of the increase in global emissions since 2015 can be attributed to urbanization. The world’s most urbanized region is Latin America with 80% of its population living in cities. This region has experienced rapid urbanization and massive privatization at the turn of the 21st century. Nevertheless, there has been little advancement in the implementation of national strategies that contribute to the energy performance of the built environment.

Residential buildings are one of the most commonplace types of buildings and their energy efficiency is a current global problem. According to the International Energy Agency, building operations account for 30% of global final energy consumption, and building construction produces 40% of total global CO2 emissions. It has been reported that lower and middle-income countries will have a 31% emission increase from 2020 to 2060. As global warming and the energy crisis worsen, a residential building sector that significantly reduces energy consumption and operational carbon emissions is crucial. A climate-responsive housing design is urged to combat climate change, addressing the UN Sustainable Development Goals 9 and 11 related to the Construction Industry.

This paper explores the implementation of energy-efficient design strategies in a prototype of a social dwelling located in four different climate zones in Latin America (Cwa–Temperate humid subtropical, Bsk–Cold semi-arid, Bsh–Hot semi-arid, and Aw–Tropical Savanna). The case studies were selected because they represent boomed cities with an increasing demand for constructing new residential projects, which face the problem of mass production of generic prototypes, without considering the sense of belonging, the use of local materials, or the climatic characteristics.

Energy-building performance simulations were run to test design guidelines derived from the Psychrometric Chart. The aim was to maximize the comfort hours throughout the year comparing the ASHRAE Standard 55-2004 and the Adaptive Comfort model. High-performance glazing, size, and orientation of windows and skylights, zone height, construction materials, natural ventilation, and the use of sunshades were tested.

Significant savings were achieved for the Bsk and Aw climates: 86% and 84% reductions of the Energy Use Intensity (lighting+heating+cooling), and 80% and 82% reductions in CO2 emissions, respectively. Results point out the urgent need to create imperative politics for energy-efficient and zero-carbon housing.