Search Results (128)

The construction sector emphasises circular economy principles that prioritise eco-design strategies, particularly the usage of secondary raw materials. The growing interest in using industrial hemp as a sustainable building material in the construction sector is driven by its versatility. Industrial hemp has been preferential in comparison to other traditional building materials due to its lower global warming impact. Claims regarding the environmental benefits of hemp-containing construction materials based on the single impact category could be misleading; therefore, life cycle assessment (LCA) studies including multiple environmental indicators should be implemented. This study aims to compare two alternative wall designs regarding their environmental impacts. The comparative LCA study for hempcrete and prefabricated walls used in residential buildings was assessed using IPCC and ReCiPe life cycle impact assessment methods. The study highlighted a significant discrepancy depending on the number of environmental indicators considered, as well as between characterised and weighted LCA results. A hempcrete wall was recognised as a slightly (13.63%) better alternative when assessed by the single-issue IPCC method, while its total burden assessed by the ReCiPe method was recognised to be significantly (2.78 times) higher. Based on the results from this case study, regulators could re-evaluate the appropriateness of reporting LCA results solely on the midpoint level, particularly when limited to a single impact indicator, while producers in the construction sector should recognise the threat of greenwashing when reporting using a single impact indicator only. Full article

Achieving carbon emission reductions in the residential building sector while maintaining economic growth represents a global challenge, particularly in rapidly developing regions with internal disparities. This study examines Jiangsu Province in eastern China—a economic hub with north-south development gradients—to develop an integrated framework for differentiated carbon reduction pathways. The methodology combines spatial autocorrelation analysis, logarithmic mean Divisia index (LMDI) decomposition, system dynamics modeling, and Tapio decoupling analysis to examine urban residential building emissions across three regions from 2016–2022. Results reveal significant spatial clustering of emissions (Moran’s I peaking at 0.735), with energy consumption per unit area as the dominant driver across all regions (contributing 147.61%, 131.82%, and 147.57% respectively). Scenario analysis demonstrates that energy efficiency policies can reduce emissions by 10.1% while maintaining 99.2% of economic performance, enabling carbon peak achievement by 2030. However, less developed northern regions emerge as binding constraints, requiring technology investments. Decoupling analysis identifies region-specific optimal pathways: conventional development for advanced regions, balanced approaches for transitional areas, and subsidies for lagging regions. These findings challenge assumptions about environment-economy trade-offs and provide a replicable framework for designing differentiated climate policies in heterogeneous territories, offering insights for similar regions worldwide navigating the transition to sustainable development. Full article

Water scarcity and energy consumption are two pressing global challenges, especially in arid regions, that require sustainable solutions in line with circular economic principles. This study investigates the feasibility of greywater recycling systems for a 10-floor residential building housing 425 occupants by optimizing non-potable water demand and energy consumption. The grey-box modeling approach and energy balance optimization analysis are used to identify effective practices for implementing greywater recycling through the evaluation of environmental and economic effects on the performance of residential buildings. The findings are that there are 18% and 40% savings in water and energy, respectively, with greywater recycling systems. The research concludes that maximum treatment and recovery efficiencies significantly enhance the performance of the systems. Thus, there are 2.25 million kWh of annual energy savings that can repay itself in 4.42 years, as well as savings in the long-term consequences. These findings contribute further to achieving the UN-SDGs on Clean Water and Sanitation (SDG 6) and Affordable and Clean Energy (SDG 7). This study contributes to a better understanding of optimizing greywater recycling systems that are practical and scalable for residential use and promote sustainable urban development with minimal environmental impacts. Full article

Applying circular economy principles to the renovation of existing buildings is increasingly recognized as essential to achieving Europe’s climate and energy goals. However, current decision-making frameworks rarely integrate life cycle carbon assessment with multi-criteria evaluation to support circular renovation strategies. This paper introduces an innovative framework that combines life cycle carbon assessment with multi-criteria decision analysis to identify and sequence circular renovation measures. The framework was applied to a residential case study in the Netherlands, using IES VE for operational carbon assessment and One Click LCA for embodied carbon assessment, with results evaluated using PROMETHEE multi-criteria analysis. Renovation measures were assessed based on operational and embodied carbon (including Module D), energy use intensity, cost, payback period, and disruption. The evaluation also introduced the embodied-to-operational carbon ratio (EOCR), a novel metric representing the proportion of embodied carbon, including Module D, relative to operational carbon savings over the building’s lifecycle. The homeowner’s preferences regarding these criteria were considered in determining the final ranking. The findings show that circular insulation options involving reused materials and designed for disassembly achieved the lowest embodied carbon emissions and lowest EOCR scores, with reused PIR achieving a 94% reduction compared to new PIR boards. The impact of including Module D on the ranking of renovation options varies based on the end-of-life scenario. The framework demonstrates how circular renovation benefits can be made more visible to decision-makers, promoting broader adoption. Full article

Green hydrogen (GH₂) is expected to play an important role in future energy systems in their fight against climate change. This study, after briefly recalling how GH₂ is produced and the main steps throughout its life cycle, analyses its current development, environmental and social impacts, and a series of case studies from selected literature showing its main applications as fuel in transportation and electricity sectors, as a heat producer in high energy intensive industries and residential and commercial buildings, and as an industrial feedstock for the production of other chemical products. The results show that the use of GH₂ in the three main areas of application has the potential of contributing to the decarbonization goals, although its generation of non-negligible impacts in other environmental categories requires attention. However, the integration of circular economy (CE) principles is important for the mitigation of these impacts. In social terms, the complexity of the value chain of GH₂ generates social impacts well beyond countries where GH₂ is produced and used. This aspect makes the GH₂ value chain complex and difficult to trace, somewhat undermining its renewability claims as well as its expected localness that the CE model is centred around. Full article

High-density cities have obvious characteristics of compact urban spatial form and intensive land use in terms of spatial environment, and have always been a topic of academic focus. As a typical coastal historical district, the Macau Peninsula pier district (mainly the Macau Inner Harbour) has a high building density and a low average street width, forming a vertical coastline development model that directly converses with the ocean. This area is adjacent to Macau’s World Heritage Site and directly related to the Marine trade functions. The distribution pattern of cultural heritage linked by the ocean has strengthened Macau’s unique positioning as a node city on the Maritime Silk Road. This text is based on the theory of urban development, integrates spatial syntax and POI analysis techniques, and combines the theories of waterfront regeneration, high-density urban form and post-industrial urbanism to integrate and deepen the theoretical framework, and conduct a systematic study on the urban spatial characteristics of the coastal area of the Macau Peninsula. This study found that (1) Catering and shopping facilities present a dual agglomeration mechanism of “tourism-driven + commercial core”, with Avenida de Almeida Ribeiro as the main axis and radiating to the Ruins of St. Paul’s and Praça de Ponte e Horta, respectively. Historical blocks and tourist hotspots clearly guide the spatial center of gravity. (2) Residential and life service facilities are highly coupled, reflecting the spatial logic of “work-residence integration-service coordination”. The distribution of life service facilities basically overlaps with the high-density residential area, forming an obvious “living circle + community unit” structure with clear spatial boundaries. (3) Commercial and transportation facilities form a “functional axis belt” organizational structure along the main road, with the Rua das Lorchas—Rua do Almirante Sérgio axis as the skeleton, constructing a “functional transmission chain”. (4) The spatial system of the Macau Peninsula pier district has transformed from a single center to a multi-node, network-linked structure. Its internal spatial differentiation is not only constrained by traditional land use functions but is also driven by complex factors such as tourism economy, residential migration, historical protection, and infrastructure accessibility. (5) Through the analysis of space syntax, it is found that the core integration of the Macau Peninsula pier district is concentrated near Pier 16 and the northern area. The two main roads have good accessibility for motor vehicle travel, and the northern area of the Macau Peninsula pier district has good accessibility for long and short-distance walking. Full article

The renewable energy sector is becoming key to the energy transformation processes of modern economies. The energy policy of one of the European countries specifies that by 2030, about 7% of energy production will come from wind sources. Because wind turbines are becoming more and more efficient, innovative projects are being created to expand their potential by integrating them with the energy systems of existing residential buildings. The analysis of the profitability of such investments may be important for the implementation of such an ambitious plan. In particular, this argument may be crucial for the growth of the potential and development prospects of distributed energy systems based on renewable energy sources. The article outlines the challenges related to forecasting generation from this energy source. The article aims to present the methodology, energy potential and forecasting results of energy generation from wind sources for two selected locations in one of the European Union countries, Poland. The NPV-Net Present Value and IRR-Internal Rate of Return methods were used for the study. These methods allowed the authors to calculate the market value of the investment with the assumed boundary criteria and determine the economic efficiency of the investment. The research was carried out in the period December 2023–November 2024 on test wind installations in households. In addition, the article indicates the challenges related to the variability of atmospheric factors and the self-consumption of the wind turbine, which is often difficult to predict due to the lack of turbine efficiency analysis. The presented models showed that the project in their implementation is fully economically justified and will allow investors to make a rational investment decision. These models can be effectively used in other countries and can also be a starting point for discussions on the direction of the development of energy systems based on renewable energy sources. Full article

Industrial cities in transition face multiple pressures of socio-economic development and carbon emission reduction. Studying the spatiotemporal evolution of urban carbon emissions helps us understand the spatial adaptability of low-carbon cities. In this study, we took Siping, an industrial city in China, as an example; spatially mapped buildings’ carbon emissions by combining statistical data and points of interest; and used exploratory spatiotemporal analysis to dynamically evolve the spatial distribution and spatiotemporal-dependent paths of carbon emissions over the years. The results presented the spatial aggregation and heterogeneity of four types of buildings’ carbon emissions in Siping. In contrast, the spatial aggregation of block-scale carbon emissions related to residential buildings and commercial buildings was stronger, and the standard deviation ellipses showed a trend of expanding outward. However, with a large total volume of carbon emissions related to industrial buildings and a large standard deviation ellipse of the distribution, targeting industrial carbon emissions remains a priority for carbon reduction. With the expansion of urban land use, the population density and carbon emission intensity of the central area decreased. Therefore, Siping should slow down its rate of land expansion, improve land use efficiency, and achieve a new balance in the complex relationship between society, economy, and the environment. Full article

The purpose of this paper is to explore the possibilities of bringing house development to a more sustainable and ecological level using the idea of the circular economy (CE) in the construction industry. Housing is an essential aspect of the economy and the building industry. The development of this sector is driven by an increasing urban population and the need to modernize existing residential buildings. Contemporary home situations should address reducing their detrimental impact on the natural environment. This is achievable by minimizing the consumption of natural resources and construction waste. This assumption is part of the core CE work, which allows for the recirculation of building materials. To discuss the underlying topics, this assumption was explored by employing a non-reactive desk research method. The review of scientific articles and studies covered the following topics: (i) the definition of CE, (ii) the shearing layers concept in building, and (iii) design for disassembly (DfD) in home construction. The second stage of evaluating the project “Domus Ex Machina” includes the following: (i) modular dimensions, (ii) prefabricated production, and (iii) adaptive designs and systems. In the discussion, this research identified several barriers to efficient CE adoption in the construction industry. The discussion highlights potential impediments to the application of the CE in housing contexts, including (i) storage and logistics issues, (ii) cost concerns and implementation challenges, (iii) policy inconsistencies across regions, and (iv) market demand and supply chain restrictions. The final paper conclusions demonstrate the significance of implementing the CE idea in housing building, hence reducing the negative impact on the environment. Full article

The construction industry increasingly relies on concrete to meet growing urban population demands. However, concrete has a high carbon footprint, which contradicts the Sustainable Development Goals and the Circular Economy policies promoted by the European Commission. The use of Recycled Aggregate Concrete (RAC) is a cost-effective circularity strategy to mitigate environmental impacts. Several countries have integrated RAC into their standards and have achieved promising circularity results. Spain is committed to enhancing resource productivity and using circular materials through practices established during the design phase. Although the residential sector plays a significant role within the construction industry, the potential for circularity of RAC in such residential building structures remains unexplored. The present study aimed to fill this gap by assessing the circularity of four scenarios in a multi-family building using a circularity assessment method for residential building structures: the CARES Framework. The results revealed that RAC, following the Structural Code requirements, can enhance the circularity performance at the material level by up to 42.82%, at the element level by 21.68%, and at the system level by 10.81%. These results demonstrated that circularity declines as the assessment levels increase, which underscores the essential integration of circular materials with adaptability and disassembly criteria. Full article

The concept of circular economy (CE) has emerged as an effective strategy for addressing resource depletion, waste generation, and environmental challenges, offering a promising path towards a more sustainable future. In the building sector, adopting CE principles can significantly mitigate environmental impacts, minimize lifecycle costs, and promote sustainability throughout a building’s lifecycle. Using a mixed-method approach via a pre-interview questionnaire and semi-structured interviews with 10 sustainability experts, this study analyses the significance of 15 CE strategies in building construction projects, assessing their importance and ranking their potential for adoption. Furthermore, this study evaluates the feasibility of applying CE principles to different building types, including storage, industrial, commercial, residential, business, and healthcare facilities. The role of lifecycle stages including initiation and planning, design, procurement, construction, operation and maintenance, and end of life is examined to identify phases with the highest potential for successfully embracing CE principles. The role of stakeholders in driving change is also analyzed. The outcomes of this study reveal that the most feasible strategies include the use of renewable energy, design for durability and longevity, prefabrication, and offsite construction. The study findings indicate that storage, industrial, and business (office) buildings are the most feasible for CE application, while the initiation and planning and design stages are identified as critical phases for embracing CE adoption. Owners and designers emerge as the stakeholders with the greatest influence on CE implementation. The results of this study provide a comprehensive overview of the feasibility of CE adoption in the building sector. These findings offer valuable insights that can inform the development of targeted strategies to support the effective adoption of CE principles. Full article

The construction industry contributes to global waste through its “take-make-dispose” model. In response, the European Commission has developed Action Plans to promote a Circular Economy (CE). However, there is currently no standardised Circularity Indicator (CI). The main barrier thereof is the lack of consensus on assessment criteria, stemming from the dispersity of advancements among the methodologies available. The CARES Framework (CARES-F) has been designed to address this issue by integrating ISO standards, Level(s), and Life Cycle Assessment (LCA) criteria into the traditional MCI framework. This innovative framework also introduces further variables from the CE perspective, such as transport impact, biomaterials, and quantitative Key Performance Indicators (KPIs) for Design for Disassembly (DfD) and Design for Adaptability (DfA). The validation is carried out on a typical Spanish residential building structure by applying the CARES-F and two micro-CIs based on the MCI. The results exhibit the low circularity of resource-intensive systems and highlight the need for secondary raw material in flow, as well as DfA criteria. These findings underscore the significance of the introduced quantitative KPIs in the CIs accuracy and demonstrate the feasibility of the CARES-F in the identification of circularity gaps and selection of optimal circular design strategies from early project stages. Full article

The number of high-rise residential buildings in China has a large base and rapid growth, with huge energy-saving potential. Most of the existing research focuses on the use of renewable energy to reduce energy consumption and optimize energy systems. When optimizing the renewable energy system configuration of residential buildings for solar-air source heat pump systems, the optimization algorithm and the setting of parameter ranges will have an impact on the optimization results. Therefore, to make up for the shortcomings of a single optimization process, this study proposes a joint solution based on simulations and multi-stage multi-objective optimization to improve the energy efficiency of the system and maximize economic benefits. This method was applied to perform energy consumption and economic optimization analyses for typical high-rise residential buildings in four cities in China (Shanghai, Nanjing, Wuhan, Chongqing) characterized by hot summers and cold winters. First, DeST software is used to model and calculate the building load. Then, TRNSYS software is used to establish a system simulation model. Next, the GenOpt program and the Hooke–Jeeves algorithm are used to perform the first stage of optimization with the lowest annual cost value as the objective function. Finally, MATLAB software and the NSGA-II algorithm are used to perform the second stage of optimization with the lowest annual cost value and the highest system energy efficiency ratio as the objective function, respectively. Moreover, the TOPSIS method is used to evaluate and sort the Pareto optimal solution sets to obtain the optimal decision solution. Overall, the two-stage optimization of the solar-air source heat pump system brings multiple benefits and a more significant improvement in overall performance compared to a single-stage optimization. In terms of energy utilization efficiency, the tilt and azimuth adjustments in the first stage allow the collectors to be better oriented towards the sun and to absorb solar energy more fully. This helps to improve the energy utilization efficiency of the system. For the economy of the system, the increase in the collector area and the reduction in the heat production of the air source heat pump in the second stage, as well as the increase in the volume of the water tank, have combined to reduce the operating costs of the system and improve its economy. Results demonstrate that the proposed two-stage optimization significantly improves the overall performance of the solar-air source heat pump system across all four cities, providing a robust framework for sustainable urban residential energy systems. This is a positive aspect for sustainability and environmental friendliness. Taken together, the two-stage optimization improves the performance of the system in a more comprehensive manner compared to the single-stage optimization. Full article

Despite significant scientific and technological advancements in earthquake engineering, earthquakes continue to cause widespread destruction of the built environment, often resulting in numerous fatalities and substantial economic losses. Southeastern Europe, which includes Croatia, is part of the Mediterranean–Trans-Asian high-seismic activity zone. This area has recently experienced a series of earthquakes which had severe consequences for both populations and economies. Notably, the types of buildings that suffered significant damage or collapse during these events still constitute a large portion of the building stock across the region. The majority of residential buildings in Croatia and neighboring areas was constructed before the adoption of modern seismic standards, indicating that a considerable part of the building stock remains highly vulnerable to earthquakes. Therefore, the main goal of this study is to identify the building types which significantly contribute to seismic risk, with the focus on Zagreb as Croatia’s largest city and the capital; collect the documentation on the structural systems and occupancy; analyze the data; and carry out the initial vulnerability assessment. This serves as a first step toward developing a new exposure and vulnerability model for Zagreb that is also applicable to all urban areas in the region with similar building stock and seismotectonic conditions. Full article

Considering the presence of airborne viruses, there is a need for renovation in refuse chutes, regarded as the first step in recycling household waste in buildings. This study aimed to revise the design of existing refuse chutes in light of the challenging experiences in waste management and public health during the coronavirus pandemic. This research primarily focused on the risks posed by various types of coronaviruses, such as the novel coronavirus (COVID-19) and acute respiratory syndrome (SARS and SARS-CoV), on stainless steel surfaces, with evidence of their survival under certain conditions. Refuse chutes are manufactured from stainless steel to resist the corrosive effects of waste. In examining the existing studies, it was observed that Casanova et al. and Chowdhury et al. found that the survival time of coronaviruses on stainless steel surfaces decreases as the temperature increases. Based on these studies, mechanical revisions have been made to the sanitation system of the refuse chute, thus increasing the washing water temperature. Additionally, through mechanical improvements, an automatic solution spray entry is provided before the intake doors are opened. Furthermore, to understand airflow and clarify flow parameters related to airborne infection transmission on residential floors in buildings equipped with refuse chutes, a computational fluid dynamics (CFD) analysis was conducted using a sample three-story refuse chute system. Based on the simulation results, a fan motor was integrated into the system to prevent pathogens from affecting users on other floors through airflow. Thus, airborne pathogens were periodically expelled into the atmosphere via a fan shortly before the intake doors were opened, supported by a PLC unit. Additionally, the intake doors were electronically interlocked, ensuring that all other intake doors remained locked while any single door was in use, thereby ensuring user safety. In a sample refuse chute, numerical calculations were performed to evaluate parameters such as the static suitability of the chute body thickness, static compliance of the chute support dimensions, chute diameter, chute thickness, fan airflow rate, ventilation duct diameter, minimum rock wool thickness for human contact safety, and the required number of spare containers. Additionally, a MATLAB code was developed to facilitate these numerical calculations, with values optimized using the Fmincon function. This allowed for the easy calculation of outputs for the new refuse chute systems and enabled the conversion of existing systems, evaluating compatibility with the new design for cost-effective upgrades. This refuse chute design aims to serve as a resource for readers in case of infection risks and contribute to the literature. The new refuse chute design supports the global circular economy (CE) model by enabling waste disinfection under pandemic conditions and ensuring cleaner source separation and collection for recycling. Due to its adaptability to different pandemic conditions including pathogens beyond coronavirus and potential new virus strains, the designed system is intended to contribute to the global health framework. In addition to the health measures described, this study calls for future research on how evolving global health conditions might impact refuse chute design. Full article