Kang, Goune; Kim, Taehoon; Kim, Yong-woo; Cho, Hunhee; Kang, Kyung-in. (2015). Statistical Analysis of Embodied Carbon Emission for Building Construction. Energy And Buildings, 105, 326 – 333.
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Abstract
Buildings are significant contributors to the greenhouse effect through emission of considerable carbon dioxide during their life cycle. Life cycle carbon resulting from buildings consists of two components: operational carbon (OC) and embodied carbon (EC). Recent studies have shown the growing significance of EC because much effort has already been invested into reducing OC. In this context, it is important to estimate and reduce EC. Because of the variability and uncertainty contained in a range of conditions, the EC of building needs to be calculated based on probabilistic analysis. This study identifies and analyzes the statistical characteristics of EC emitted from building construction materials. It was aimed at buildings constructed of reinforced concrete and nine representative construction materials. Descriptive statistics analysis, correlation analysis, and a goodness-of-fit test were performed to describe the statistical characteristics of EC. In addition, a case study was carried out to show the difference between the deterministic and probabilistic estimations. Presenting statistical information on EC data and the differences between the deterministic and probabilistic values, the result shows the necessity and reasonability of the probabilistic method for EC estimation. (C) 2015 Published by Elsevier B.V.
Keywords
Construction; Construction Materials; Greenhouse Gases; Probability Theory; Goodness-of-fit Tests; Quantitative Research; Building Materials; Correlation; Descriptive Statistics; Embodied Carbon; Goodness-of-fit; Buildings (structures); Reinforced Concrete; Statistical Analysis; Embodied Carbon Emission; Greenhouse Effect; Carbon Dioxide; Life Cycle Carbon; Operational Carbon; Oc; Probabilistic Analysis; Building Construction Materials; Statistics Analysis; Correlation Analysis; Probabilistic Estimations; Statistical Information; Ec Data; Probabilistic Method; Ec Estimation; Life-cycle; Energy Measurement; System Boundary
Bender, W.; Waytuck, D.; Wang, S.; Reed, D. A. (2018). In Situ Measurement of Wind Pressure Loadings on Pedestal Style Rooftop Photovoltaic Panels. Engineering Structures, 163, 281 – 293.
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Abstract
The installation of rooftop photovoltaic (PV) arrays is increasing throughout the US. Until recently, pedestal type PV framing systems for rooftops were basically designed using procedures from the ASCE7-10 Components and Cladding Standard for rooftop equipment. The 2011 Japanese Standard Load design guide on structures for photovoltaic arrays was useful in characterizing the pressure coefficients on rooftops, but the Standard employs different wind speed and importance factors, making its use in the US quite limited, Even the updated 2017 version is written for a different audience. Because rooftop pressure loadings are high due to flow separation, SEAOC and other organizations contracted boundary layer wind tunnel tests of panels attached to rooftops to ascertain if the ASCE7-10 equipment loadings were appropriate. The investigations resulted in new standards for pedestal-style arrays that appear in Chapter 29 of ASCE7-16. However, the new standards are limited to simple geometries and orientations, and the dynamics of the simply-supported thin PV plates do not appear to be considered. Questions regarding the ability of the boundary tunnels to simulate accurately the turbulence at the scale required for the attached panels have been raised. In response, very limited full-scale investigations in large-scale tunnels and in situ have been undertaken to calibrate the tunnel results. The results of this paper represent one of these calibration investigations. Specifically, in situ full-scale net wind pressure loadings on a rooftop PV array in a pedestal-style framing system located on the three story Hogue Technology Building of Central Washington University (CWU) in Ellensburg, Washington were measured. The CWU campus has a rural setting in a region with steady winds: Ellensburg is located in the Kittitas Breezeway portion of the Northwest wind power region. Indeed, the Wild Horse Wind and Solar Farm is located on the outskirts of town. The data described here were collected from April through August 2014. The measured net pressure coefficient time series were similar to those for rooftop pressure loadings for low-rise buildings described in the literature such as the Wind Engineering Research Field Laboratory at Texas Tech University (Ham and Bienkiewicz, 1998 [1]; Levitan and Mehta, 1992 [2]). The analysis of the net pressure time series data included an examination of the minimum, maximum, mean, and RMS values. Preliminary results suggest that the range of the values is larger than assumed in the ASCE7 Standard, and that the magnitude of the loadings vary considerably spatially over the multiple panel array. The pressure loading measurements are ongoing.
Keywords
Building Integrated Photovoltaics; Buildings (structures); Calibration; Design Engineering; Pressure Measurement; Roofs; Solar Cell Arrays; Standards; Time Series; Turbulence; Wind Tunnels; Japanese Standard Load Design Guide; Wind Pressure Loading Measurements; Asce7-10 Components-cladding Standard; Tunnel Calibration; Texas Tech University; Kittitas Breezeway Portion; Wild Horse Wind And Solar Farm; Ellensburg; Central Washington University; Hogue Technology Building; Boundary Layer Wind Tunnel Test; Flow Separation; Multiple Panel Array; Wind Engineering Research Field Laboratory; Net Pressure Coefficient Time Series; Northwest Wind Power Region; Pedestal-style Framing System; Pv Plates; Rooftop Equipment; Pedestal Style Rooftop Photovoltaic Panels; Solar-arrays; Loads; Simulation; Wind Engineering; Photovoltaic Modules; Solar Energy; Full-scale Measurements; Wind Loadings; Photovoltaic Cells; Roofing; Wind Power; Structural Engineering; Boundary Layers; Cladding; Wind Tunnel Testing; Solar Cells; In Situ Measurement; Framing; Photovoltaics; Engineering Research; Wind Measurement; Pressure; Panels; Wind Pressure; Design Standards; Fluid Dynamics; Low Rise Buildings; Colleges & Universities; Wind Speed; United States--us
Parsaee, Mojtaba; Demers, Claude M. H.; Lalonde, Jean-francois; Potvin, Andre; Inanici, Mehlika; Hebert, Marc. (2020). Human-Centric Lighting Performance of Shading Panels in Architecture: A Benchmarking Study with Lab Scale Physical Models Under Real Skies. Solar Energy, 204, 354 – 368.
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Abstract
This study investigates shading panels' (SPs) impacts on daylighting features in a lab scale model in terms of parameters representing potential human eyes' biological responses identified as image forming (IF) and non-image forming (NIF). IF responses enable vision and NIF responses regulate internal body clocks known as circadian clocks. Human-centric lighting evaluates photopic units, representing IF responses, and melanopic units representing NIF responses, combined with correlated color temperature (CCT) of light for potential biological effects. SPs' impacts on such parameters of daylighting have not yet been studied. Previous research mostly studied panels' impacts on visual comfort and glare related to IF responses. This research explores the impact of SPs' color, reflectance, orientation, and openness on photopic and melanopic units and CCT of daylighting inside a 1:50 physical scale model of a space. Approximately 40 prototypes of SPs were evaluated. An experimental setup was designed under outdoor daylighting conditions to capture high dynamic range (HDR) images inside the model. HDR images were post processed to calculate and render the distribution of photopic and melanopic units, melanopic/photopic (M/P) ratios and CCTs in the captured viewpoint of the model. Results reveal the behavior of SPs' color, reflectance, orientation, and openness in modifying daylighting parameters related to biological responses. Bluish panels, in particular, increase daylighting melanopic units and CCTs whereas reddish panels increase photopic units and reduce CCTs. The research results were discussed to provide an outline for future developments of panels to adapt daylighting to occupants' IF and NIF responses.
Keywords
Models & Modelmaking; Shades & Shadows; Daylighting; Color Temperature; Benchmarking (management); Ecological Houses; Eye Tracking; Circadian Rhythms; Adaptive Design; Healthy Lighting; High Performance Façade; Photobiology; Responsive Building; Design; Sensitivity; Illuminance; Systems; Spaces; Impact; Glare; High Performance Facade; Reflectance; Scale Models; Biological Effects; Human Performance; Prototypes; Parameter Modification; Lighting; Shading; Eye (anatomy); Color; Parameter Identification; Light Effects; Panels; Mathematical Models; Images; Biological Clocks; Orientation
Recart, Carolina; Dossick, Carrie Sturts. (2022). Hygrothermal Behavior Of Post-retrofit Housing: A Review Of The Impacts Of The Energy Efficiency Upgrade Strategies. Energy & Buildings, 262.
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Abstract
Improving energy efficiency of existing buildings is currently among the most diverse and extensive mitigation opportunities to reduce energy consumption and CO2 emissions worldwide. However, the implementation of energy-saving measures has caused unintended impacts, often correlated with dampness and mold growth connected to poor hygrothermal behavior in residential buildings. The focus of this paper is research on the impacts of energy efficiency measures (EEMs) in regard to the hygrothermal behavior resulting from the interaction of building's envelope, indoor environment, and occupants. The results show that dampness and mold growth are by no means exclusive to neglected houses, since the occurrence of these pathologies actually depends upon a complex set of conditions, including indoor and outdoor conditions, occupancy, maintenance, ventilation, mechanical systems, and quality of the envelope. We found that building envelope post-retrofit may suffer from higher levels of moisture and dampness, higher condensations risks, and a faster structural degradation caused by higher humidity levels. We also found that measuring hygrothermal behavior may play a role in more accurately predicting both overall energy consumption and occupant comfort. While hygrothermal behavior may be problematic, we found evidence that retrofits may moderately improve thermal comfort. (c) 2022 Elsevier B.V. All rights reserved.
Keywords
Energy Consumption; Energy Consumption Of Buildings; Carbon Emissions; Geothermal Ecology; Housing; Thermal Comfort; Building Envelopes; Dampness And Mold; Energy Retrofits; Hygrothermal Behavior; Residential Buildings; Unintended Impacts; Indoor Air-quality; Low-income; Environmental-quality; Assistance-program; Building Envelope; Health; Ventilation; Weatherization; Performance; Mold Growths; Indoor Environments; Moisture Effects; Energy Efficiency; Residential Areas; Mechanical Systems; Moisture Content; Green Buildings; Energy Conservation; Carbon Dioxide; Mold; Emission Measurements; Emissions; Mitigation; Buildings; Occupancy; Retrofitting; Mechanical Properties
Choi, Kunhee; Lee, Hyun Woo; Mao, Zhuting; Lavy, Sarel; Ryoo, Boong Yeol. (2016). Environmental, Economic, and Social Implications of Highway Concrete Rehabilitation Alternatives. Journal Of Construction Engineering And Management, 142(2).
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Abstract
Currently, there is no comprehensive benchmark of life-cycle assessment for the rigid pavement alternatives for highway rehabilitation. To fill this gap, the major objective of this study is to investigate the environmental, economic, and social impacts of the three most widely adopted rigid pavement choices through a life-cycle assessment approach with custom-built economic input-output life-cycle assessment (EIO-LCA) models. Quantity takeoffs were performed for each alternative assuming a 1-lane-km highway rehabilitation. Subsequently, the construction costs of each alternative were computed in order to determine the present values for a life span of 50years, while at the same time accounting for a different life expectancy for each pavement rehabilitation strategy. The present values were then incorporated into a corresponding EIO-LCA model. The results clearly indicate that continuously reinforced concrete pavement (CRCP) is the most sustainable choice and much preferable to the other alternatives for minimizing negative environmental, economic and social impacts from the life-cycle perspective. This finding champions a wider adoption of CRCP for future sustainable transportation infrastructure development projects, as CRCP's relatively high initial construction cost can be recouped by long-term sustained benefits. The results and findings of this study can serve as a solid foundation for industry practitioners and decision-makers to make better-informed project decisions when choosing the most sustainable pavement alternatives from a life-cycle perspective. (C) 2015 American Society of Civil Engineers.
Keywords
Construction Industry; Environmental Management; Life Cycle Costing; Product Life Cycle Management; Project Management; Reinforced Concrete; Road Building; Socio-economic Effects; Sustainable Development; Economic Implications; Environmental Implications; Industry Practitioners; Sustainable Transportation Infrastructure Development Projects; Continuously Reinforced Concrete Pavement; Crcp; Eio-lca Model; Life Span; Construction Costs; Custom-built Economic Input-output Life-cycle Assessment Models; Rigid Pavement Alternatives; Highway Concrete Rehabilitation Alternatives; Life-cycle Assessment Approach; Social Implications; Life-cycle Assessment; Pavement; Asphalt; Pavement Rehabilitation; Environmental Assessment; Economic Factors; Land Use
Frank, A.; Carroll-Nellenback, Jonathan; Alberti, M.; Kleidon, A. (2018). The Anthropocene Generalized: Evolution of Exo-Civilizations and Their Planetary Feedback. Astrobiology, 18(5), 503 – 518.
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Abstract
We present a framework for studying generic behaviors possible in the interaction between a resource-harvesting technological civilization (an exo-civilization) and the planetary environment in which it evolves. Using methods from dynamical systems theory, we introduce and analyze a suite of simple equations modeling a population which consumes resources for the purpose of running a technological civilization and the feedback those resources drive on the state of the host planet. The feedbacks can drive the planet away from the initial state the civilization originated in and into domains that are detrimental to its sustainability. Our models conceptualize the problem primarily in terms of feedbacks from the resource use onto the coupled planetary systems. In addition, we also model the population growth advantages gained via the harvesting of these resources. We present three models of increasing complexity: (1) Civilization-planetary interaction with a single resource; (2) Civilization-planetary interaction with two resources each of which has a different level of planetary system feedback; (3) Civilization-planetary interaction with two resources and nonlinear planetary feedback (i.e., runaways). All three models show distinct classes of exo-civilization trajectories. We find smooth entries into long-term, sustainable steady states. We also find population booms followed by various levels of die-off. Finally, we also observe rapid collapse trajectories for which the population approaches n=0. Our results are part of a program for developing an Astrobiology of the Anthropocene in which questions of sustainability, centered on the coupled Earth-system, can be seen in their proper astronomical/planetary context. We conclude by discussing the implications of our results for both the coupled Earth system and for the consideration of exo-civilizations across cosmic history.
Keywords
Anthropocene Epoch; Holocene Epoch; Climatology; Earth System Science; Climate Change; Earth (planet); Biosphere; Easter-island; Earth; Population; Anthropocene; Astrobiology; Civilization; Dynamical System Theory; Exoplanets; Population Dynamics
Roches, Simone Des; Bell, Michael A.; Palkovacs, Eric P. (2020). Climate-Driven Habitat Change Causes Evolution in Threespine Stickleback. Global Change Biology, 26(2), 597 – 606.
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Abstract
Climate change can shape evolution directly by altering abiotic conditions or indirectly by modifying habitats, yet few studies have investigated the effects of climate-driven habitat change on contemporary evolution. We resampled populations of Threespine Stickleback (Gasterosteus aculeatus) along a latitudinal gradient in California bar-built estuaries to examine their evolution in response to changing climate and habitat. We took advantage of the strong association between stickleback lateral plate phenotypes and Ectodysplasin A (Eda) genotypes to infer changes in allele frequencies over time. Our results show that over time the frequency of low-plated alleles has generally increased and heterozygosity has decreased. Latitudinal patterns in stickleback plate phenotypes suggest that evolution at Eda is a response to climate-driven habitat transformation rather than a direct consequence of climate. As climate change has reduced precipitation and increased temperature and drought, bar-built estuaries have transitioned from lotic (flowing-water) to lentic (still-water) habitats, where the low-plated allele is favoured. The low-plated allele has achieved fixation at the driest, hottest southernmost sites, a trend that is progressing northward with climate change. Climate-driven habitat change is therefore causing a reduction in genetic variation that may hinder future adaptation for populations facing multiple threats.
Keywords
Gasterosteus-aculeatus; Natural-selection; 3-spined Stickleback; Armor; Populations; Patterns; Reductions; Adaptation; Capacity; Package; Climate Change; Gasterosteus Aculeatus; Intraspecific Variation; Latitudinal Gradient; Rapid Evolution; Resurvey; Space-for-time
Horn, Erin; Proksch, Gundula. (2022). Symbiotic And Regenerative Sustainability Frameworks: Moving Towards Circular City Implementation. Frontiers In Built Environment, 7.
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Abstract
Growing in popularity, the circular city framework is at the leading-edge of a larger and older transitional dialogue which envisions regenerative, circular, and symbiotic systems as the future of urban sustainability. The need for more research supporting the implementation of such concepts has been often noted in literature. To help address this gap, this holistic review assesses a range of pertinent sustainability frameworks as a platform to identify actionable strategies which can be leveraged to support and implement circular city goals. This assessment is grounded in a holistic overview of related frameworks across interdisciplinary and scalar domains including circular city, the food-water-energy nexus, circular economy, bioeconomy, industrial symbiosis, regenerative design, and others. Building on these interrelationships, the applied strategies espoused within these publications are synthesized and assessed in the context of circular city implementation. From an initial 250 strategies identified in literature, thirty-four general implementation strategies across six thematic areas are distinguished and discussed, finding strong overlaps in implementation strategies between frameworks, and opportunities to further develop and harness these synergies to advance circular city toward sustainable urban futures.
Keywords
Circular City; Implementation Strategies; Literature Review; Circular Economy; Fwe-nexus; Regenerative Design; Systems Integration; Environmental Assessment; Rooftop Greenhouses; Anaerobic-digestion; Urban Agriculture; Built Environment; Waste Management; Climate-change; Carbon Nexus; Food Nexus; Economy
Estiri, Hossein. (2016). Differences in Residential Energy Use between US City and Suburban Households. Regional Studies, 50(11), 1919 – 1930.
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Abstract
This paper applies path analysis to household-level data from the US residential sector to study differences in energy consumption between self-identified city and suburban households. Results show that, on average, suburban households consume more energy in residential buildings than their city-dweller counterparts. This variation in energy consumption is due to differences in: (1) characteristics of the household and the housing unit, independently, and (2) interactions between the household and housing characteristics in the city and suburban households. Findings of this study provide new insights into how regional policies can be implemented differently in suburbs and cities to reduce energy consumption.
Keywords
Urban Form; Electricity Consumption; Land-use; Impact; Sector; Sprawl; Determinants; Appliance; Mobility; Density; Energy Use; Residential Sector; City-dwellers; Suburbanites; Households; Path Analysis; Suburban Areas; Cities; Housing; Energy Consumption; Comparative Analysis; Data Processing; Residential Energy; Suburbs; Residential Buildings; Residential Areas; Energy Policy; Regional Analysis; Regional Studies; United States--us
Simonen, K.; Huang, M.; Aicher, C.; Morris, P. (2018). Embodied Carbon as a Proxy for the Environmental Impact of Earthquake Damage Repair. Energy And Buildings, 164, 131 – 139.
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Abstract
In evaluating the life cycle environmental impacts of buildings, the contributions of seismic damage are rarely considered. In order to enable a more comprehensive assessment of a building's environmental impact by accounting for seismic events, this project developed an environmental impact database of building component seismic damage - the largest of its kind known to date - by combining data from Carnegie Mellon University's Economic Input-Output Life Cycle Analysis (LCA) database with cost estimates of repair previously developed for FEMA's Performance Assessment Calculation Tool (PACT), a software that models probabilistic seismic damage in buildings. Fifteen indicators of environmental impacts were calculated for the repair of approximately 800 building components for up to five levels of seismic damage, capturing 'embodied' impacts related to cradle-to-gate manufacturing of building materials, products, and equipment. Analysis of the data revealed that non-structural and architectural finishes often dominated the environmental impacts of seismic damage per dollar spent in repair. A statistical analysis was performed on the data using Principal Component Analysis, confirming that embodied carbon, a popular metric for evaluating environmental impacts in building LCAs, is a suitable proxy for other relevant environmental impact metrics when assessing the impact of repairing earthquake damage of buildings. (C) 2018 Elsevier B.V. All rights reserved.
Keywords
Life-cycle Assessment; Input-output; Buildings; Life Cycle Assessment; Seismic Analysis; Performance-based Design; Economic Input-output; Principal Component Analysis; Energy And Climate Change; Architectural Engineering; Carbon; Carbon Cycle; Earthquake Damage; Earthquakes; Environmental Impact; Environmental Management; Databases; Finishes; Environmental Assessment; Building Components; Construction Materials; Life Cycle Engineering; Life Cycle Analysis; Data Bases; Damage Assessment; Aseismic Buildings; Statistical Analysis; Equipment Costs; Cost Estimates; Data Processing; Data Analysis; Seismic Activity; Cost Analysis; Principal Components Analysis; Performance Assessment; Life Cycles; Repair; Impact Damage; Building Materials; Economic Analysis; Software