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
Technologies and sustainable development are interrelated from a thermodynamic perspective, with industrial ecology (IE) as a major point of access for studying the relationship in the Anthropocene... Show moreTechnologies and sustainable development are interrelated from a thermodynamic perspective, with industrial ecology (IE) as a major point of access for studying the relationship in the Anthropocene. To offer insights into the potential offered by thermodynamics in the environmental sustainability analysis of technologies, this thesis develops a hierarchical framework which defines techno-systems at four levels, viz. the ecosphere, the anthroposphere, and individual technologies, the latter being further subdivided into a foreground system and a supply chain. The role and applications of thermodynamic analysis in IE and broader human-environment systems is reviewed. The production of US bioethanol, global biofuels, and Chinese titania is studied by applying a series of thermodynamic sustainability indicators, combining thermodynamic analysis with material flow analysis (MFA), and combing thermodynamic analysis with life cycle assessment (LCA), respectively, in the framework. The outcomes of the review and case studies show that taking account of thermodynamics is a necessity when analyzing the environmental sustainability of technologies, and integrating energy analysis, exergy analysis, and emergy analysis with LCA and MFA is both feasible and useful. The thesis then discusses the limitations and challenges of the developed framework and ends with three recommendations for the further development of thermodynamic analysis for sustainability. Show less
