Ho, Chung; Lee, Hyun Woo; Gambatese, John A. (2020). Application of Prevention Through Design (PTD) to Improve the Safety of Solar Installations on Small Buildings. Safety Science, 125.
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Abstract
As a viable, clean and renewable energy resource, solar energy has gained a significant interest in the US residential sector. Most solar systems are installed on rooftops to take advantage of available space and reduce land use. However, this installation environment also exposes workers to unique safety hazards related to existing roof conditions such as slippery roofing materials, irregular roof layouts, and steep roof slopes. Although Prevention through Design (ND) has been widely considered as an effective way to address safety issues during the design phase, little to no studies have applied ND to improve safety in solar energy installations. To fill this knowledge gap, this research aimed to investigate how, during the design phase, to address the safety concerns of solar workers when installing solar energy systems on residential buildings. Through a series of interviews, four case studies, and a seminar, seven solar ND attributes were identified: roofing materials, roof slopes, roof accessories, panel layouts, fall protection systems, lifting methods and electrical systems. Based on the attributes, a ND protocol was developed that can serve as guidance for implementing ND in solar installations. This paper presents the research activities and findings, and feedback gained from solar contractors through a seminar on the study. The study is expected to contribute to reducing safety hazards by implementing ND, help improve safety performance in solar installations on small residential buildings and support the promotion of safety in sustainable construction.
Keywords
Roofing Materials; Renewable Energy Sources; Sustainable Construction; Solar Energy; Clean Energy; Construction Safety; Prevention Through Design; Small Buildings; Solar Installations; Buildings (structures); Construction Industry; Hazards; Occupational Safety; Roofs; Safety; Solar Power; Sustainable Development; Steep Roof Slopes; Design Phase; Solar Energy Installations; Solar Workers; Installing Solar Energy Systems; Residential Buildings; Seven Solar Ptd Attributes; Roof Accessories; Ptd Protocol; Solar Contractors; Safety Performance; Viable Energy Resource; Clean Energy Resource; Renewable Energy Resource; Us Residential Sector; Solar Systems; Installation Environment; Unique Safety Hazards; Roof Conditions; Slippery Roofing Materials; Irregular Roof Layouts; Issues; Accident Prevention; Protocol; Energy Sources; Residential Areas; Land Use; Prevention; Design; Falls; Occupational Hazards; Contractors; Residential Energy; Protection Systems; Renewable Energy; Buildings; Roofing; Layouts
Jung, Meen Chel; Kang, Mingyu; Kim, Sunghwan. (2022). Does Polycentric Development Produce Less Transportation Carbon Emissions? Evidence from Urban Form Identified by Night-Time Lights Across US Metropolitan Areas. Urban Climate, 44.
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Abstract
Identifying the comprehensive metropolitan urban form is important to propose effective policies to mitigate transportation carbon emissions. A publicly accessible night-time light dataset was used to identify urban centers and develop two polycentric indices to compute the composition and configuration of urban form, respectively. We used the most populous 103 U.S. metropolitan statistical areas (MSAs), with their corresponding transportation carbon emissions, polycentric indices, population sizes, gross domestic product (GDP) per capita, and road network densities. We first explored the typology of urban form and classified MSAs into six types based on two polycentric indices. We then introduced correlation analysis and statistical models to test the relationships between polycentric urban form and transportation carbon emissions. We found: (1) more urban centers lead to more emissions (compositional dimension), (2) more spatially distributed urban centers result in less emissions (configurational dimension), and (3) population and GDP per capita are positively related to carbon emissions. These findings suggest the importance of measuring two polycentric dimensions separately but using them together. Urban planners should consider mixed strategies that combine the traditional intra-center-based smart growth principles and the metropolitan-level inter-centers spatial plan to effectively counteract climate change.
Keywords
Polycentric Urban Form; Urban Centers; Carbon Emissions; Night-time Lights; Smart Growth; Climate Change; Co2 Emissions; Spatial Structure; Satellite Imagery; Cities; Patterns; Trends; Growth; Determinants; China
Alberti, Marina. (2015). Eco-Evolutionary Dynamics in an Urbanizing Planet. Trends In Ecology & Evolution, 30(2), 114 – 126.
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Abstract
A great challenge for ecology in the coming decades is to understand the role humans play in eco-evolutionary dynamics. If, as emerging evidence shows, rapid evolutionary change affects ecosystem functioning and stability, current rapid environmental change and its evolutionary effects might have significant implications for ecological and human wellbeing on a relatively short time scale. Humans are major selective agents with potential for unprecedented evolutionary consequences for Earth's ecosystems, especially as cities expand rapidly. In this review, I identify emerging hypotheses on how urbanization drives eco-evolutionary dynamics. Studying how human-driven micro-evolutionary changes interact with ecological processes offers us the chance to advance our understanding of eco-evolutionary feedbacks and will provide new insights for maintaining biodiversity and ecosystem function over the long term.
Keywords
Biological Evolution; Urbanization; Climate Change; Ecosystems; Well-being; Co-evolution; Eco-evolutionary Dynamics; Ecosystem Function; Urban Ecosystems; Ecological Consequences; Phenotypic Plasticity; Rapid Evolution; Regime Shifts; Elevated Co2; Biodiversity; Selection; Community; Patterns
Zhu, Panyu; Gilbride, Michael; Yan, Da; Sun, Hongshan; Meek, Christopher. (2017). Lighting Energy Consumption in Ultra-Low Energy Buildings: Using a Simulation and Measurement Methodology to Model Occupant Behavior and Lighting Controls. Building Simulation, 10(6), 799 – 810.
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Abstract
As building owners, designers, and operators aim to achieve significant reductions in overall energy consumption, understanding and evaluating the probable impacts of occupant behavior becomes a critical component of a holistic energy conservation strategy. This becomes significantly more pronounced in ultra-efficient buildings, where system loads such as heating, cooling, lighting, and ventilation are reduced or eliminated through high-performance building design and where occupant behavior-driven impacts reflect a large portion of end-use energy. Further, variation in behavior patterns can substantially impact the persistence of any performance gains. This paper describes a methodology of building occupant behavior modeling using simulation methods developed by the Building Energy Research Center (BERC) at Tsinghua University using measured energy consumption data collected by the University of Washington Integrated Design Lab (UW IDL). The Bullitt Center, a six-story 4831 m(2) (52,000 ft(2)) net-positive-energy urban office building in Seattle, WA, USA, is one of the most energy-efficient buildings in the world (2013 WAN Sustainable Building of the Year Winner). Its measured energy consumption in 2015 was approximately 34.8 kWh/(m(2)a (TM) yr) (11 kBtu/(ft(2)a (TM) yr)). Occupant behavior exerts an out-sized influence on the energy performance of the building. Nearly 33% of the end-use energy consumption at the Bullitt Center consists of unregulated miscellaneous electrical loads (plug-loads), which are directly attributable to occupant behavior and equipment procurement choices. Approximately 16% of end-use energy is attributable to electric lighting which is also largely determined by occupant behavior. Key to the building's energy efficiency is employment of lighting controls and daylighting strategies to minimize the lighting load. This paper uses measured energy use in a 330 m(2) (3550 ft(2)) open office space in this building to inform occupant profiles that are then modified to create four scenarios to model the impact of behavior on lighting use. By using measured energy consumption and an energy model to simulate the energy performance of this space, this paper evaluates the potential energy savings based on different occupant behavior. This paper describes occupant behavior simulation methods and evaluates them using a robust dataset of 15 minute interval sub-metered energy consumption data. Lighting control strategies are compared via simulation results, in order to achieve the best match between occupant schedules, controls, and energy savings. Using these findings, we propose a simulation methodology that incorporates measured energy use data to generate occupant schedules and control schemes with the ultimate aim of using simulation results to evaluate energy saving measures that target occupant behavior.
Keywords
Control-systems; Patterns; Offices; Lighting Control; Ultra-low Energy Building; Occupant Behavior; Building Simulation; Energy Consumption
Ianchenko, Alex; Simonen, Kathrina; Barnes, Clayton. (2020). Residential Building Lifespan and Community Turnover. Journal Of Architectural Engineering, 26(3).
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Abstract
Environmental impact studies within the built environment rely on predicting building lifespan to describe the period of occupation and operation. Most life cycle assessments (LCAs) are based on arbitrary lifespan values, omitting the uncertainties of assessing service life. This research models the lifespan of American residential housing stock as a probabilistic survival distribution based on available data from the American Housing Survey (AHS). The log-normal, gamma, and Weibull distributions were fit to demolition data from 1985 to 2009 and these three models were compared with one another using the Bayesian information criterion. Analysis revealed that the estimated average housing lifespan in the United States is 130 years given model assumptions, although a probabilistic approach to lifespan can yield higher accuracy on a case-by-case basis. Parameters for modeling housing lifespan as log-normal, gamma, and Weibull survival functions are published with the intent of further application in LCA. The application of probabilistic housing lifespan models to community-wide turnover and integration with existing simulations of natural disaster are proposed as potential ways to achieve community sustainability and resilience goals. (c) 2020 American Society of Civil Engineers.
Keywords
Energy-consumption; Service Life; Cycle; Demolition; Emissions; Design; Impact; Model; Housing Stock Lifetime; Residential Buildings; Housing Turnover; Life Cycle Assessment; Service Life Prediction
Zhong, Bo; Wu, Shuang; Sun, Geng; Wu, Ning. (2022). Farmers’ Strategies to Climate Change and Urbanization: Potential of Ecosystem-based Adaptation in Rural Chengdu, Southwest China. International Journal Of Environmental Research And Public Health, 19(2).
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Abstract
Ecosystem-based adaptation (EbA) is emerging as a cost-effective approach for helping people adapt to climate and non-climate changes. Nowadays, climate change and urbanization have affected agricultural systems, but it is not clear how rural communities have responded or adapted to those changes. Here, we chose two typical villages in the Chengdu Plain, southwest China, through sociological surveys on 90 local farmers with a semi-structured questionnaire, participatory observation, geospatial analysis of land use and land cover, and a literature review, to explore the local people's perception of changes or disturbances and their adaptation strategies from the perspective of EbA. The results showed that climate change and urbanization had impacted agricultural systems dramatically in the last 40 years. In two case-study sites, climate change and urbanization were perceived by most local farmers as the main drivers impacting on agricultural production, but various resource-use models containing abundant traditional knowledge or practices as well as modern tools, such as information communication technology (ICT), were applied to adapt to these changes. Moreover, culture service through the adaptive decoration of rural landscapes is becoming a new perspective for implementing an EbA strategy. Finally, our findings highlighted the potential value of an EbA strategy for sustaining urban-rural integrated development and enhancing the resilience of agricultural systems.
Keywords
Ecosystem-based Adaptation (eba); Chengdu Plain; Climate Change; Urbanization; Agricultural System; Traditional Knowledge Or Practice; Functioning Ecosystem; Agro-biodiversity; Resilience; Services; Diversity; Polls & Surveys; Spatial Analysis; Topography; Rural Communities; Biodiversity; Questionnaires; Adaptation; International Organizations; Land Use; Climate Change Adaptation; Canals; Irrigation; Land Cover; Ecosystems; Case Studies; Literature Reviews; Agriculture; Farmers; Environmental Economics; Sustainable Development; Rural Areas; Gross Domestic Product--gdp; Agricultural Production; Urban Areas; Cultural Heritage; China
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