Use of thermal insulation in the envelope to mitigate energy consumption in the face of climate change for mid-western Brazil

Abstract

As scientific research shows a progressive increase in Earth temperature, climate change is recognized as a key global challenge for the 21st century. Studying the consequences of this phenomenon has gained worldwide importance, including in the field of buildings. It starts from the problematic that comes from the housing models that, at present, are already built with inadequate thermal insulation, questioning what internal conditions will bring benefits in these future heating scenarios. In places with hot climates such as in the Brazilian savannah, this subject is even more important because an effective countermeasure is necessary in reducing the cooling load of buildings. High temperatures lead to longer demand for air conditioning, which results in a significant increase in building energy consumption. In this way, this work has the general objective to analyze the effects of global warming on the consumption of buildings with different insulation in the envelope, in face of the climatic changes. The emissions scenario A2 of the Fourth Report (AR4) of the Intergovernmental Panel on Climate Change (IPCC) was considered. The methodological procedures consist of five steps: preparation of the climate files for Future Scenarios (time-slices 2020, 2050 and 2080) from the file without influence of global warming (1961-1990), called Base Scenario; definition of a dwelling for study object (Tbase); quantification of global warming impacts on building consumption; elaboration of intervention proposals in the object of study, defining four typologies (Tbase and T1 to T3) by adopting the use of insulation, in the first one (T1) was applied EPS, in the second (T2) rockwool and in the third (T3) glasswool, in the last stage, the energy consumption for cooling was estimated, considering the main facade as north for all cases. Under the effects of global warming, the results showed the annual average temperature and relative humidity of the external air of the Base Scenario from 26.73 ° C to 32.48 ° C (+ 5.75 ° C) and 69.08% to 53.67% (-22%), up to the 2080 scenario, respectively. Energy consumption is directly influenced by the effects of global warming, Tbase's energy consumption in the current scenario presents increases for the 2080 scenario of 54.18%, the T1 was 40.73%, the T2 of 41.97% and the T3 ratio of 41.87%. With the use of insulation in the typologies T1 to T3, the energy consumption reduced in the base scenario by 30.58%, 30.62% and 30.64% respectively. This fact proves the importance and effectiveness of the use of more resilient envelopes as a strategy to mitigate climate change. It is concluded that considering the useful life of 50-year-old buildings, it is necessary to re-think the current constructive specifications, incorporating interventions to absorb the impacts of climate change, pointing out guidelines on how to build today, to provide better and more resilient climate habitability in future climate scenarios.