Sustentabilidade na construção civil : avaliação do ciclo de vida energético e de emissões de CO2 em edificação histórica de origem portuguesa e contemporânea

Abstract

The environmental impact generated through greenhouse gas emission, of which carbon dioxide (CO2) corresponds to 55% of global gas emission, is mainly due to activities related to construction sector during lifecycle of buildings. The Brazilian construction sector generates emissions in quantity similar to developed countries, even the general amount of emission added to all other country sectors are below to the global emission index. This is due to majority of electricity generation be obtained from hydraulic source and renewable fuels consumption on transport sector, as ethanol and biodiesel. Besides the gas emissions, the sector presents high energy consumption. Since it is the necessity to decrease the environmental impacts associated to both aspects, it is increasing the research related to this subject. The objective of this work is quantifying the energy consumption and CO2 emissions during the life-cycle of two single-family residential buildings One of them is a historical Portuguese-style’ building and the second one is a contemporaneous house, both located in Novo Hamburgo, Southern Brazil. They were used energetic life-cycle energy analysis (LCEA) and life-cycle carbono dioxide emission analysis (LCCO2A) during the pre-use, use, maintenance and post-use phases, in a cradle to grave scheme. Energy factors and CO2 emission data were collected from consolidated literature and results were calculated using electronic spreadsheet. Contemporaneous building obtained indicated an increase of 47,83% on energy consumption and an increase of 49,36% on total emissions compared to historical building. So the first is associated to greater quantity of environmental impact, even this building type presents lower quantity of raw material bulk. Ultimately, it is possible to conclude that it is necessary an improvement on the conventional building construction way to the future buildings to be more sustainable and less harmful to environment than historical buildings and presents technology and material more efficient that contemporaneous buildings.