Material circularity and energy efficiency are highly relevant and intertwined issues for the transition towards a carbon-neutral and circular built environment. In the Netherlands, the building... Show moreMaterial circularity and energy efficiency are highly relevant and intertwined issues for the transition towards a carbon-neutral and circular built environment. In the Netherlands, the building sector has been rendered a priority towards a circular and low-carbon society. This thesis explored potential solutions for these twin issues in light of a novel technological system. This system presents an energy–material efficiency solution for energy renovation of building stocks with prefabricated concrete elements (PCEs) with recycled CDW as feedstock. Life cycle assessment (LCA) and life cycle costing (LCC) were combined with dynamic material flow analysis (MFA) to estimate the economic and environmental implications at both a product level and a national level. Show less
Building stock growth around the world drives extensive material consumption and environmental impacts. Future impacts will be dependent on the level and rate of socioeconomic development, along... Show moreBuilding stock growth around the world drives extensive material consumption and environmental impacts. Future impacts will be dependent on the level and rate of socioeconomic development, along with material use and supply strategies. Here we evaluate material-related greenhouse gas (GHG) emissions for residential and commercial buildings along with their reduction potentials in 26 global regions by 2060. For a middle-of-the-road baseline scenario, building material-related emissions see an increase of 3.5 to 4.6 Gt CO2eq yr-1 between 2020-2060. Low- and lower-middle-income regions see rapid emission increase from 750 Mt (22% globally) in 2020 and 2.4 Gt (51%) in 2060, while higher-income regions shrink in both absolute and relative terms. Implementing several material efficiency strategies together in a High Efficiency (HE) scenario could almost half the baseline emissions. Yet, even in this scenario, the building material sector would require double its current proportional share of emissions to meet a 1.5 degrees C-compatible target.Building construction causes large material-related emissions which present a serious decarbonization challenge. Here, the authors show that the building material sector could halve emissions by increasing efficiency until 2060 but even then its emissions would be twice as high as needed to meet the 1.5 degrees C target. Show less
Buildings have become a major concern because of their high energy use and carbon emissions. Thus, a material-efficient prefabricated concrete element (PCE) system was developed to incorporate... Show moreBuildings have become a major concern because of their high energy use and carbon emissions. Thus, a material-efficient prefabricated concrete element (PCE) system was developed to incorporate construction and demolition waste as feedstock for residential building energy renovation by over-cladding the walls of old buildings. By conducting life cycle assessment and life cycle costing using the payback approach, this study aims to explore the life cycle performance of energy conservation, carbon mitigation, and cost reduction of the PCE system in three European member states: Spain, the Netherlands, and Sweden. The results show that the energy payback periods for Spain, the Netherlands, and Sweden were 20.45 years, 17.60 years, 19.95 years, respectively, and the carbon payback periods were 23.33 years, 16.78 years, and 8.58 years, respectively. However, the financial payback periods were less likely to be achieved within the building lifetime, revealing that only the Swedish case achieved a payback period within 100 years (83.59 years). Thus, circularity solutions were considered to shorten the PCE payback periods. Using secondary materials in PCE fabrication only slightly reduced the payback period. However, reusing the PCE considerably reduced the energy and carbon payback periods to less than 6 years and 11 years, respectively in all three cases. Regarding cost, reusing the PCE shortened the Swedish payback period to 29.30 years, while the Dutch and Spanish cases achieved investment payback at 42.97 years and 85.68 years, respectively. The results can be extrapolated to support the design of sustainable building elements for energy renovation in Europe. Show less
Zhang, C.; Hu, M.; Sprecher, B.; Yang, X.; Zhong, X.; Li, C.; Tukker, A. 2021
