Urban environments - construction

Title

Regional climate consequences of large-scale cool roof and photovoltaic array deployment

Reference

Environmental Research Letters Volume 6 Number 3 (2011) 034001
doi:10.1088/1748-9326/6/3/034001

Author(s)

Dev Millstein and Surabi Menon

Study type

Peer Review Journal

Abstract

Modifications to the surface albedo through the deployment of cool roofs and pavements (reflective materials) and photovoltaic arrays (low reflection) have the potential to change radiative forcing, surface temperatures, and regional weather patterns. In this work we investigate the regional climate and radiative effects of modifying surface albedo to mimic massive deployment of cool surfaces (roofs and pavements) and, separately, photovoltaic arrays across the United States. We use a fully coupled regional climate model, the Weather Research and Forecasting (WRF) model, to investigate feedbacks between surface albedo changes, surface temperature, precipitation and average cloud cover. With the adoption of cool roofs and pavements, domain-wide annual average outgoing radiation increased by 0.16 ± 0.03 W m - 2 (mean ± 95% C.I.) and afternoon summertime temperature in urban locations was reduced by 0.11-0.53 °C, although some urban areas showed no statistically significant temperature changes. In response to increased urban albedo, some rural locations showed summer afternoon temperature increases of up to + 0.27 °C and these regions were correlated with less cloud cover and lower precipitation. The emissions offset obtained by this increase in outgoing radiation is calculated to be 3.3 ± 0.5 Gt CO₂ (mean ± 95% C.I.). The hypothetical solar arrays were designed to be able to produce one terawatt of peak energy and were located in the Mojave Desert of California. To simulate the arrays, the desert surface albedo was darkened, causing local afternoon temperature increases of up to + 0.4 °C. Due to the solar arrays, local and regional wind patterns within a 300 km radius were affected. Statistically significant but lower magnitude changes to temperature and radiation could be seen across the domain due to the introduction of the solar arrays. The addition of photovoltaic arrays caused no significant change to summertime outgoing radiation when averaged over the full domain, as interannual variation across the continent obscured more consistent local forcing.

Policy theme(s)

Climate change and energy >> Climate change mitigation >> Geoengineering
Urban environment >> Urban planning >> Construction

Keywords

photovoltaics, cool roofs,  CO₂ offsets, radiative forcing, urban environment

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.globalcoolcities.org/wp-content/uploads/2011/07/Regional-Effects-of-Cool-Roofs.pdf
This study is free to view

Contact the study author at:

dmillstein@lbl.gov

Title

A Longitudinal Study on the Carbon Emissions of a New Residential Development

Reference

Sustainability 2011, 3(8), 1170-1189;
doi:10.3390/su3081170

Author(s)

Jukka Heinonen, Antti Säynäjoki  and Seppo Junnila

Study type

Peer Review Journal

Abstract

Buildings account for nearly 50% of all greenhouse gases globally. While this has been widely recognized, the GHG mitigation strategies have traditionally concentrated on reducing the use phase emissions, as over 90% of the emissions are generated during the use phase according to several studies. However, two current developments increase the importance of the construction phase emissions and the embodied emissions of the building materials. Firstly, the improvements in the energy efficiency of buildings directly increase the relative share of the construction phase emissions. Secondly, the notification of the temporal allocation of the emissions increases the importance of the carbon spike from construction. While these perspectives have been noted, few studies exist that combine the two perspectives of the construction and the use phase. In this paper, we analyze the implications of low-carbon residential construction on the life cycle emissions of a residential area with a case study. Furthermore, we demonstrate that when the temporal allocation of the emissions is taken into account, the construction phase emissions can hinder or even reverse the carbon mitigation effect of low-carbon buildings for decades.

Policy theme(s)

Climate change and energy >> Greenhouse gas emissions >> Industrial emissions
Urban environment >> Urban planning >> Construction

Keywords

life cycle assessment; carbon; climate change; buildings; construction

Entry Source:

Selected for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.mdpi.com/2071-1050/3/8/1170/
This study is free to view

Contact the study author at:

jukka.heinonen@aalto.fi

Title

Using corporate social responsibility benchmarking framework to identify and assess corporate social responsibility trends of real estate companies owning and developing shopping centres

Reference

Journal of Cleaner Production
Volume 19, Issue 13, September 2011, Pages 1486-1493

Author(s)

Idalina Dias Sardinha, Lucas Reijnders and Paula Antunes

Study type

Peer Review Journal

Abstract

Shopping centres that include retail activities have come in for criticism as to their environmental, architectural and social impacts. However, the sector has been applying corporate social responsibility (CSR) practices. In an attempt to identify the best practices regarding CSR and trends therein we developed a CSR benchmarking of companies from the real estate sector owning and developing shopping centres. Based on information from websites, annual, environmental and sustainability reports, and customer services department's information, in 2004 and 2010, a comparative CSR benchmarking was performed on 23 real estate companies with shopping centres based in Europe, China, Australia and the USA. The CRS benchmarking framework focused on reported CSR practices and included categories and sub-categories of evaluation in four domains: (1) external results, (2) internal results, (3) management processes and (4) learning and innovation. The framework was inspired by the sustainability balanced scorecard structure. The United Kingdom real estate sector's companies studied did relatively well when evaluated by the framework used in this study. The highest ranked real estate companies applied sustainable or environmental buildings standards and did show a commitment to transparency and CSR disclosure. The positive evolution of CSR practices in the 23 companies studied in 2004 and 2010 may reflect efforts to improve competitiveness and the reputation of the companies with shopping centres through CSR initiatives.

Policy theme(s)

Sustainable consumption and production >> Sustainable production >> Sustainable business and industry
Sustainable development and policy assessment >> Sustainable economic development >> Sustainable business and industry
Urban environment >> Urban planning >> Construction

Keywords

Corporate social responsibility benchmarking, Real estate sector, Shopping centres

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.sciencedirect.com/science/article/pii/S0959652611001272
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Contact the study author at:

idalinasardinha@iseg.utl.pt

Title

A model for quantifying construction waste in projects according to the European waste list

Reference

Waste Management
Volume 31, Issue 6, June 2011, Pages 1261-1276

Author(s)

C. Llatas

Study type

Peer Review Journal

Abstract

The new EU challenge is to recover 70% by weight of C&D waste in 2020. Literature reveals that one major barrier is the lack of data. Therefore, this paper presents a model which allows technicians to estimate C&D waste during the design stage in order to promote prevention and recovery. The types and quantities of CW are estimated and managed according to EU guidelines, by building elements and specifically for each project. The model would allow detection of the source of the waste and to adopt other alternative procedures which delete hazardous waste and reduce CW. Likewise, it develops a systematic structure of the construction process, a waste classification system and some analytical expressions which are based on factors. These factors depend on technology and represent a standard on site. It would allow to develop a database of waste anywhere. A Spanish case study is covered. Factors were obtained by studying over 20 dwellings. The source and types of packaging waste, remains, soil and hazardous waste were estimated in detail and were compared with other studies. Results reveal that the model can be implemented in projects and the chances of reducing and recovery C&D waste could be increased, well above the EU challenge.

Policy theme(s)

Urban environment >> Urban planning >> Construction

Keywords

N/A

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.sciencedirect.com/science/article/pii/S0956053X11000559
There is a fee to view this study in full

Contact the study author at:

alp11931@fct.unl.pt

Title

A model for quantifying construction waste in projects according to the European waste list

Reference

Waste Management, Volume 31, Issue 6, June 2011, Pages 1261-1276

Author(s)

C. Llatas

Study type

Peer Review Journal

Abstract

The new EU challenge is to recover 70% by weight of C&D waste in 2020. Literature reveals that one major barrier is the lack of data. Therefore, this paper presents a model which allows technicians to estimate C&D waste during the design stage in order to promote prevention and recovery. The types and quantities of CW are estimated and managed according to EU guidelines, by building elements and specifically for each project. The model would allow detection of the source of the waste and to adopt other alternative procedures which delete hazardous waste and reduce CW. Likewise, it develops a systematic structure of the construction process, a waste classification system and some analytical expressions which are based on factors. These factors depend on technology and represent a standard on site. It would allow to develop a database of waste anywhere. A Spanish case study is covered. Factors were obtained by studying over 20 dwellings. The source and types of packaging waste, remains, soil and hazardous waste were estimated in detail and were compared with other studies. Results reveal that the model can be implemented in projects and the chances of reducing and recovery C&D waste could be increased, well above the EU challenge.

Policy theme(s)

Waste >> Waste reduction
Urban environment >> Urban planning >> Construction

Keywords

N/A

Entry Source:

Shortlisted for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.sciencedirect.com/science/article/pii/S0956053X11000559
There is a fee to view this study in full

Contact the study author at:

alp11931@fct.unl.pt

Title

Roof selection for rainwater harvesting: Quantity and quality assessments in Spain

Reference

Water Research
Volume 45, Issue 10, May 2011, Pages 3245-3254

Author(s)

Ramon Farreny, Tito Morales-Pinzón, Albert Guisasola, Carlota Tayà, Joan Rieradevall and Xavier Gabarrell

Study type

Peer Review Journal

Abstract

Roofs are the first candidates for rainwater harvesting in urban areas. This research integrates quantitative and qualitative data of rooftop stormwater runoff in an urban Mediterranean-weather environment. The objective of this paper is to provide criteria for the roof selection in order to maximise the availability and quality of rainwater. Four roofs have been selected and monitored over a period of 2 years (2008-2010): three sloping roofs - clay tiles, metal sheet and polycarbonate plastic - and one flat gravel roof. The authors offer a model for the estimation of the runoff volume and the initial abstraction of each roof, and assess the physicochemical contamination of roof runoff. Great differences in the runoff coefficient (RC) are observed, depending mostly on the slope and the roughness of the roof. Thus, sloping smooth roofs (RC > 0.90) may harvest up to about 50% more rainwater than flat rough roofs (RC = 0.62). Physicochemical runoff quality appears to be generally better than the average quality found in the literature review (conductivity: 85.0 ± 10.0 µS/cm, total suspended solids: 5.98 ± 0.95 mg/L, total organic carbon: 11.6 ± 1.7 mg/L, pH: 7.59 ± 0.07 upH). However, statistically significant differences are found between sloping and flat rough roofs for some parameters (conductivity, total organic carbon, total carbonates system and ammonium), with the former presenting better quality in all parameters (except for ammonium). The results have an important significance for local governments and urban planners in the (re)design of buildings and cities from the perspective of sustainable rainwater management. The inclusion of criteria related to the roof's slope and roughness in city planning may be useful to promote rainwater as an alternative water supply while preventing flooding and water scarcity.

Policy theme(s)

Urban environment >> Urban planning >> Construction
Water >> Urban water management

Keywords

City ecodesign, Runoff coefficient, Sustainable urbanism, Stormwater runoff, Urban environment, Water management

Entry Source:

Selected for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.sciencedirect.com/science/article/pii/S0043135411001540
There is a fee to view this study in full

Contact the study author at:

ramon@ineditinnova.com

Title

Climate change impact and risks of concrete infrastructure deterioration

Reference

Engineering Structures
Volume 33, Issue 4, April 2011, Pages 1326-1337

Author(s)

Mark G. Stewart, Xiaoming Wang and Minh N. Nguyen

Study type

Peer Review Journal

Abstract

Atmospheric CO2 is a major cause of reinforcement corrosion in bridges, buildings, wharves, and other concrete infrastructure in Australia, United States, United Kingdom and most other countries. The increase in CO2 levels associated with global warming will increase the likelihood of carbonation-induced corrosion. Moreover, temperature rises will increase corrosion rates. Clearly, the impact of climate change on existing and new infrastructure is considerable, as corrosion damage is disruptive to society and costly to repair. The paper describes a probabilistic and reliability-based approach that predicts the probability of corrosion initiation and damage (severe cracking) for concrete infrastructure subjected to carbonation and chloride-induced corrosion resulting from elevated CO2 levels and temperatures. The atmospheric CO2 concentration and local temperature and relative humidity changes with time over the next 100 years in the Australian cities of Sydney and Darwin are projected based on nine General Circulation Models (GCMs) under (i) high CO2 emission scenario, (ii) medium CO2 emission scenario, and (iii) CO2 emission reduction scenario based on policy intervention. The probabilistic analysis included the uncertainty of CO2 concentration, deterioration processes, material properties, dimensions, and predictive models. It was found that carbonation-induced damage risks can increase by over 400% over a time period to 2100 for some regions in Australia. Damage risks for chloride-induced corrosion increase by no more than 15% over the same time period due to temperature increase, but without consideration of ocean acidity change in marine exposure. Corrosion loss of reinforcement is not significant. The results were most sensitive to increases in atmospheric CO2.

Policy theme(s)

Urban environment>> Urban planning>>Urban construction

Keywords

Risk; Structural reliability; Climate change; Corrosion; Concrete

Entry Source:

N/A

Referred to in EC doc:

Selected for Science for Environment Policy News Alert

View this study at:

http://www.sciencedirect.com/science/article/pii/S0141029611000241
There is a fee to view this study in full

Contact the study author at:

mark.stewart@newcastle.edu.au

Title

Life cycle assessment of building materials: Comparative analysis of energy and environmental impacts and evaluation of the eco-efficiency improvement potential

Reference

Building and Environment
Volume 46, Issue 5, May 2011, Pages 1133-1140

Author(s)

Ignacio Zabalza Bribián, Antonio Valero Capilla and Alfonso Aranda Usón

Study type

Peer Review Journal

Abstract

The building industry uses great quantities of raw materials that also involve high energy consumption. Choosing materials with high content in embodied energy entails an initial high level of energy consumption in the building production stage but also determines future energy consumption in order to fulfil heating, ventilation and air conditioning demands.
This paper presents the results of an LCA study comparing the most commonly used building materials with some eco-materials using three different impact categories. The aim is to deepen the knowledge of energy and environmental specifications of building materials, analysing their possibilities for improvement and providing guidelines for materials selection in the eco-design of new buildings and rehabilitation of existing buildings.
The study proves that the impact of construction products can be significantly reduced by promoting the use of the best techniques available and eco-innovation in production plants, substituting the use of finite natural resources for waste generated in other production processes, preferably available locally.
This would stimulate competition between manufacturers to launch more eco-efficient products and encourage the use of the Environmental Product Declarations.
This paper has been developed within the framework of the 'LoRe-LCA Project' co-financed by the European Commission's Intelligent Energy for Europe Program and the 'PSE CICLOPE Project' co-financed by the Spanish Ministry of Science and Technology and the European Regional Development Fund.

Policy theme(s)

Sustainable consumption and production >> Sustainable production >> Sustainable business and industry
Urban environment >> Urban planning >> Construction

Keywords

LCA, Building materials, Embodied energy, Eco-efficiency

Entry Source:

Selected for Science for Environment Policy News Alert

Referred to in EC doc:

N/A

View this study at:

http://www.sciencedirect.com/science/article/pii/S0360132310003549
There is a fee to view this study in full

Contact the study author at:

zabal@unizar.es