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Small to medium sized water utilities face serious challenges to meet broad sustainability objectives, because of technical, human and financial constraints and limited involvement in the inter-utility benchmarking. Most of these utilities are unable to address the performance gaps for various functional components, such as personnel, operational, financial, etc., of their water supply systems and rely on emergency response. Even if the information obtained from such benchmarking process is available, the outcome (indices) showing performance of these components, at the utility level, is useful for top level management. The operations management is more interested in the performance of sub-components (under each functional component) of the water supply systems within the utility. An intra-utility performance management model is conceptualized and developed for effective decision making at both the levels. A hierarchical based top-down approach initiates from overall sustainability objectives at the top, followed by primary and secondary performance measures of the sub-components, and indicators (basic building blocks) receive inputs from data/decision variables at the bottom. The model assesses the performance of each component and sub-component as ‘ high ’, ‘medium’ , or ‘low’ . Fuzzy based technique has been employed to deal with uncertainty issues due to data limitations and vagueness in expert knowledge. Sensitivity analysis helped to rank the indicators for their contribution in decision making. The model is implemented for a medium sized utility containing three sub-systems in the Okanagan Basin (BC, Canada). The results demonstrate the model's practicality to efficiently achieve sustainable performance in small to medium sized water utilities. [ABSTRACT FROM AUTHOR]

An efficient waste treatment strategy should be cost-effective and minimize potential impacts on various stakeholders and the environment. This study proposes a decision framework that can model the stakeholder's conflicting priorities over the sustainability criteria, when selecting a municipal solid waste treatment option. The proposed framework compares life cycle sustainability impacts of selected options and develops a weighing scheme for combining impacts based on stakeholders' preferences. It then uses game theory to help the stakeholders fairly share the costs and benefits, and guides the stakeholders to reach an agreement on a mutually sustainable and pragmatic solution. In this study, the application of the framework to select a waste-to-energy technology for Vancouver, Canada is demonstrated. The case study discusses the prospect of producing refuse-derived fuel by cement industry and the municipality. Results show that the cement industry and the municipality may mutually benefit from the refuse-derived fuel, if the industry pays a tipping fee of $0.077–0.96 per kg waste to access the required amount of solid waste from the municipality. The outcome of the framework can help in the approval and application of an overall sustainable option by both stakeholders and in making the negotiation more efficient and timely. [ABSTRACT FROM AUTHOR]

Abstract: Emergy synthesis is capable of quantifying environmental resources and services, as well as economic and human services, that are used up directly or indirectly to make a product available. However, a controversial aspect of emergy synthesis is the lack of research characterizing and documenting uncertainties in the emergy evaluation process. Uncertainty can arise from analysis of numerous components and flows in a complex environmental system. The reliability of emergy synthesis results may be undermined by both the inherent uncertainty of emergy parameters and models, and by a lack of knowledge regarding the certainty of resulting outputs. This paper explores the utility of fuzzy-based methods in emergy synthesis. Applying fuzzy set theory facilitates the gradual assessment of Unit Emergy Values (UEVs) as a set of possible UEVs. In other words, uncertainty of UEVs is described with the aid of a membership function valued in the real unit interval [0, 1]. The proposed fuzzy-based emergy synthesis has been applied for Life Cycle Assessment (LCA) of a transportation infrastructure system. A paved road, with different pavement options (i.e. asphalt and concrete), has been selected as a case study to highlight the impacts of propagation of different sources of uncertainties in the emergy evaluation process and decision making. Results indicate that fuzzy-based modeling can provide better insight for both emergy and LCA practitioners. The developed methodology provides transparency that should be an integral part of an emergy-based decision making process. [Copyright &y& Elsevier]

Thermochemical water-splitting processes are among the most promising options for producing sustainable and green hydrogen due to being extremely environmentally benign. Being extensively investigated in the literature, the thermochemical copper-chlorine cycle has demonstrated much promise in this regard as one of the most efficient options for thermochemically obtaining hydrogen. Thus, this study focuses on investigating the exergoeconomic performances of the different variants of the copper-chlorine cycle including the three-, four-, and five-step versions. All cycles are modeled and simulated in Aspen-plus software by considering a recovery of thermal energy from industrial waste flue gases in addition to internal heat recovery. Moreover, a hydrogen production capacity of 668 kg/h is considered for all cycles. The Specific Exergy Costing methodology is employed to study the exergoeconomic performance of each cycle. All cycles are initially examined in terms of the cost rates of energy transfer and hourly levelized cost rates for each step. The cycle variants are further examined through a comparative assessment of several performance parameters including hydrogen cost rates, overall cost rates of energy transfer, and overall hourly levelized cost rates. According to the performed analyses, the three-step variant of the cycle that constitutes a high-temperature electrolysis process produces hydrogen at the lowest cost rate (0.83 $/kg) while the four-step cycle produces hydrogen at the highest cost rate (1.82 $/kg). Furthermore, the hydrolysis step is found to have the highest hourly levelized cost rates for all variants of the cycle. Several factors that impact the hydrogen cost rate are also examined comprehensively. In addition, the extent to which the hydrogen cost rate is sensitive to those factors is discussed. [Display omitted] • Exergoeconomic analyses of three variants of thermochemical copper-chlorine cycle. • Thermal management schemes incorporated for each cycle. • Comparative assessment of the exergoeconomic performances of all cycles. • Hydrogen production capacity of 668 kg/h for each cycle. [ABSTRACT FROM AUTHOR]

Improving the environmental performance of built environments has received wider interest in the recent past. Asset management is an under-utilized strategy to enhance and maintain desired environmental performance of a building at low life cycle costs (LCC). Current asset management decision-making methods are not fully capable of incorporating future technological changes and complex time sensitive environmental demands. There is a knowledge gap in incorporating factors such as environmental performance, risk and time sensitivity to foster dynamic asset management decision making. This paper presents a multi-period asset management method for public buildings to minimize LCC and attain climate action goals. A scenario planning approach is used to incorporate future changes in technologies, costs and organizational policies. Risk based prioritization is used to compare and select maintenance alternatives in a given period. Value at risk is used to identify the lowest risk capital planning strategy for an organization. The proposed approach was demonstrated using an operating aquatic centre building in British Columbia, Canada. Three possible future scenario were considered. Proposed method was used to develop multi-period maintenance plans for future scenarios. Based on the analysis, Great Transitions scenario is expected to achieve the least financial risk. The proposed approach enable capital asset planning by complying with changing climate action targets in a stochastic environment. [ABSTRACT FROM AUTHOR]

Road transportation is responsible for 23% of Canada's Greenhouse Gas (GHG) inventory due to complete dependence on fossil fuels. Decarbonizing the transportation sector using alternative energy sources is one of the most effective strategies to achieve GHG emission reduction targets. Alternative transportation modes such as electric and hydrogen fuel cell based vehicles are considered as scalable technologies for decarbonizing the transportation sector. However, there is a knowledge gap for a systematic investigation approach on regional viability of aforementioned vehicles. The main objective of this paper is to evaluate the financial feasibility and environmental impact of the electric light duty vehicles (LD-EVs) and hydrogen fuel cell light duty vehicles (LD-HFCVs) use in Canada. A life cycle thinking based approach has been proposed to compare costs and emissions of transportation based on electric and Hydrogen with traditional fossil fuel. The carbon offset saving was used to quantify the economic impact of GHG reduction. The carbon taxes for selected provinces were recommended as a potential policy implementation to reduce transport based GHG emissions. The results indicate that the provinces with low emission factor electric grids have a higher potential for LD-EV based transportation system in terms of costs and footprint. Presently LD-HFCVs are less desirable due to high purchase and operational cost. Development of a Hydrogen based transportation system through the production of cost effective hydrogen is preferable for provinces with a higher emission factor electric grids. [ABSTRACT FROM AUTHOR]

Neighborhood densification is a strategy primarily applied to reduce per capita infrastructure and land requirement. In particular, densification alters residential landscaping that in turn affects water distribution systems. An integrated study of the water-energy-carbon (WEC) dynamics of water distribution and residential landscaping under neighborhood densification is lacking in the published literature. A conceptual framework was developed and applied as a case study to a planned neighborhood in the Okanagan Valley (BC, Canada). For this neighborhood, 11 alternative designs with varying combinations of single-family and multi-family lots representing different residential densities were investigated. Water consumption, energy use, and net carbon emissions by water distribution and residential landscaping systems were combined and represented by ecological footprint. The results show that per capita ecological footprint has a power relationship with net residential density despite of a linear relationship between population and net residential density. The power relationship reveals a high dependency of per capita ecological footprint on residential density, which helps to identify an optimal density. Two-dimensional analysis of the WEC nexus scenarios indicates that xeriscaping can reduce per capita ecological footprint ranging from roughly 1% reduction in high density to 66% in low density neighborhood. Also, the effects of xeriscaping on the WEC nexus are highly density dependent. This research can be extended by including varying neighborhood configuration and building stories. The results emphasize the importance of amending relevant policies for constructing medium to high-density buildings in urban neighborhoods to achieve an optimal WEC nexus. [ABSTRACT FROM AUTHOR]

Small distribution systems face numerous challenges in drinking water production because of financial insufficiency. In these systems, where treatment installation is often based on a simple step of disinfection, every element of water production and monitoring is under the responsibility of local operators. As a result, drinking water quality in small systems becomes more sensible to operators' interventions, which should be considered in the comprehension of the variability of water quality. The objective of this study is to define the impact of human operational factors on drinking water quality. Observations and individual interviews were conducted with operators of 21 small systems in two Canadian provinces. Drinking water quality was sampled at the same time in the systems under study. A first analysis allowed to categorize systems according to their human operational factors and to identify factors contributing the most to drinking water quality. Results suggest that the most important human operational factor is experience, which has a positive correlation with other factors, as motivation and autonomy. In order to determine the relative influence of human operational factors, raw water quality and the applied treatment were also considered. Multi-level analysis has revealed that global human operational factors do not explain global drinking water quality, as raw water quality and treatment are the main explanatory parameters. However, when drinking water quality was assessed daily, only the variability of human operational factors could explain the variability of drinking water quality. [ABSTRACT FROM AUTHOR]

The proliferation in the deployment of electric vehicles has brought up several challenges in the planning and operation of power systems. The health of power system components and the satisfaction of electric vehicle users are becoming equally important with the increasing presence of electric vehicles on the power grid. The charging strategy is crucial as it plays a significant role in shaping users' behavior to deal with the adverse effects of electric vehicles on grid components. There is a lack of a proper unified framework for the charging management, which considers both the system perspectives such as transformer overloading, shortage of power, and users perspectives such as satisfaction, charging urgency, and privacy. This paper presents a fully decentralized cooperative approach/strategy for charging electric vehicles. The solution is achieved by developing a decentralized iterative algorithm based on a consensus concept to protect the privacy of EV owners. The charging priority factor is incorporated to address the charging urgency of electric vehicles. Multiple electric vehicles can be charged simultaneously without a central decision-maker or coordinator using the proposed strategy. As a result, electric vehicles fulfill their charging needs by the deadline to maximize user satisfaction while respecting their constraints and limitations imposed by the available charging power and charging station capacity. The convergence of the proposed approach is demonstrated by observing the charging of multiple electric vehicles. The results are benchmarked against the centralized approach to verify the effectiveness of the proposed approach. • A decentralized approach is based on peer-to-peer communication among neighbors. • Each EV user maximizes satisfaction and fulfills the charging requirements. • The charging priority factor addresses the charging urgency. • Decentralized and centralized approaches for EV charging are benchmarked. [ABSTRACT FROM AUTHOR]

Sustainable built environment has been of interest to many stakeholders in the recent years. However, life cycle economic performance as one of the key dimensions of sustainability has not been sufficiently investigated for buildings constructed using off-site construction methods such as modular construction. This research has proposed a framework to benchmark the life cycle economic sustainability of single-family modular homes. First, suitable economic performance criteria were selected and suitable measurable economic performance indicators were developed under each criterion. A performance level function was established for each indicator by which all indicators can be calculated and presented by a normalized performance level that enables combining quantitative and qualitative indicators. Subsequently, a multi-criteria decision analysis-based methodology was employed to develop a set of economic sustainability indices at the criteria level and also at the overall economic sustainability performance level. To compare and contrast the developed indices of a given modular building with the performance of similar conventional buildings, suitable performance benchmarks scales were established using the data of the historical economic performances of conventional homes. To examine the application of the proposed framework, two case study modular homes in British Columbia, Canada were analyzed. The results showed that both benchmarking homes performed 'Excellent' with respect to the overall economic sustainability. However, improvements are required to enhance the economic performance with respect to a number of criteria. The proposed framework can assist the construction decision makers, developers, and contractors with making informed decisions on the selection of the construction method. Furthermore, it can be used to address the underperforming areas over the life cycle of a modular building, even if the decision on the construction method has already been made. [ABSTRACT FROM AUTHOR]

Abstract: Activities in offshore oil and gas (OOG) that cause environmental impacts can be systematically managed through an environmental management system (EMS). Environmental performance evaluation (EPE) is an essential part of an EMS. However, previous studies on EPE indicate that existing lists of indicators little insight into how indicators are modified to more accurately assess environmental performance. In this paper, a way is proposed to identify and define specific environmental performance indicators on a case-by-case basis, which consists of five steps: (1) describing environmental requirements; (2) determining favourable outcomes corresponding to the requirements; (3) identifying required activities or issues to achieve the outcomes; (4) searching for proper measures of the activities or issues; and (5) generating a list of key indicators. Based on these steps, a quality function deployment (QFD) approach is developed to determine key indicators and evaluate environmental performance. To handle uncertainties in QFD, the decision makers’ evaluations are quantified through rough numbers using the concept of rough sets. The outputs of the proposed approach are different environmental performance indices. Using these indices, decision makers can easily determine whether an improved performance has been achieved through an EMS. The proposed approach is transparent and promising for use as a unified tool for EPE. An application of the proposed approach is demonstrated through a numerical example. [Copyright &y& Elsevier]

Urban densification is seen as a possible solution in response to the intense urbanization and sustainable development. Urban densification counteracts the negative effects of urban sprawl, which include increased mobility challenges, demand of natural resources, greenhouse gas emissions, and encroachment on green spaces. In spite of its benefits, urban densification creates pressure on the existing buried water infrastructure (BWI) (i.e., drinking water, wastewater, and stormwater) and the environment. The impacts of urban densification on the level of service of BWI are overlooked in the published literature. This study aims to identify and discuss the key drivers, induced pressures, their effects on the level of service, corresponding impacts, and finally the possible responses using the Driver-Pressure-State-Impact-Response (DPSIR) linkage-based sustainability assessment framework. The DPSIR framework was selected due to its simplicity and most powerful communication tool between environment and society. The outcome of this study provide a conceptual model, which interlinks the steps (i) identification of system indicators, (ii) data processing, (iii) decision making, and (iv) impact analysis with factors influencing the integrated level of service of BWI at three different levels. Together these steps create a basis for evaluating the level of service of multifaceted BWI. The uncertainties associated with scenarios, datasets, and model development could be a challenge during the application of proposed conceptual framework. The proposed conceptual model may serve as reference for multi-stakeholders in understanding the dynamic balance between urban densification, BWI, and sustainable use of water services. • DPSIR framework has been adopted to highlight the impacts of urban densification. • Integrated level of service of buried water infrastructure is defined at three levels. • A conceptual model has been developed to assess the integrated level of service. [ABSTRACT FROM AUTHOR]

Recharging infrastructure (RI) deployment plays a vital role in improving the public recharging availability for transport electrification. Decarbonizing transportation using low-emission electricity requires massive RI network. Even though the consumers are reluctant to purchase electric vehicles (EVs) until RIs are sufficiently placed, the investors are not willing to invest in RIs due to recharging demand uncertainties. Therefore, a scientific planning framework is needed to ensure the sustainable deployment of EV-RIs in complex networks. In this study, a lifecycle thinking-based multi-period infrastructure-planning framework is proposed to develop sustainable public EV-RIs in an urban context. This framework consists of a temporal model to find the dynamic EV-RI demands, a stochastic model to obtain travel distances, and a multi-objective optimization model to select the best desirable capacities and locations for potential EV-RIs. A case study of a typical medium-scale municipality in Canada was assessed using the proposed framework and validated using conventional infrastructure planning scenarios. The geo-processing data, regional travel behaviors, and recharging characteristics were used as model inputs. The results of the case study showed that the proposed framework can be used to estimate multi-period public recharging demands, minimize lifecycle costs, maximize service coverage and infrastructure utilization, and ensure reasonable paybacks compared to conventional planning approaches. Moreover, this framework can be used to compare different investment assistances, which are required in the early stages of the RI deployment process to encourage investors. Furthermore, government and private institutions can use this framework to identify recharging demands, permitting, and developing RIs in the long-run. • Lifecycle thinking-based planning framework is proposed to develop EV recharging infrastructure. • Temporal and spatial models were used to obtain EV recharging demands and travel distances. • Location-based data, regional travel behaviors, and temporal variations were used as inputs. • Multi-objective optimization was used to obtain capacities and locations for potential facilities. • The method was applied to medium-scale community and validated using expert opinion. [ABSTRACT FROM AUTHOR]

The absence or lack of effective stakeholder engagement during project life cycle, especially at the earlier stages of planning and implementation often negatively impacts the expected performance of projects. These coupled consequences of the lack of contextual knowledge from the stakeholders as well as lack of their support in the field necessitates effective stakeholder engagement. However, this integration faces challenges such as limitations of project resources and conflicting interests of the stakeholders. In this sense, project resources can be allocated based on the priorities of the fields of conflicts to facilitate stakeholder engagement of the projects. The goal of this paper is to provide a framework to enhance effectiveness of the stakeholder engagement in projects by systematically ranking the potential conflicts while combining the viewpoints of stakeholders and project management team. For this purpose, we draw on stakeholder theory, value-based management, matrix-based dependency modeling, and Total Quality Management to develop a stakeholder engagement framework while considering fuzzy inputs for reflecting the ambiguities at the project life cycle. The proposed approach is then applied to plan stakeholder engagement in case of a green building project in Iran. Practically, application of the proposed framework facilitates stakeholder engagement for project managers in line with sustainable goals through early assessment of the fields of potential conflicts of interests. • Developing the sustainability paradigm by integrating various theories and concepts. • Extending the literature of stakeholder engagement in projects. • Integrating stakeholders' and project decision-makers' viewpoints into decisions. • Prioritizing stakeholder engagement actions by assessing their conflicting interests. • Proposing and implementing a quantitative approach to organize steering committees in projects. [ABSTRACT FROM AUTHOR]

Low impact developments (LIDs) are becoming increasingly popular in North America as viable solution for sustainable runoff management. Although hydrological performance of LIDs in relation to climates is readily available, there is still a gap on the evaluation of environmental and economic impacts of these infrastructures. We have evaluated the cradle-to- site lifecycle environmental and economic impacts of four LIDs using a case study of the stormwater management system at UBC Okanagan campus in BC, Canada. The environmental impacts and costs are determined via ReCiPe, TRACI, and net present value (NPV) method, respectively, and incorporated to obtain eco-efficiency of these LIDs. We found that the box planter and naturally occurring wetland on campus are the best LIDs with lower impacts (approximately 2.5% of the total impacts) than other LIDs. The cost savings from wetland are enormous due to zero construction and periodic maintenance after every five years. The box planter and wetland occupy the most favorable quadrant III of the eco-efficiency matrix whilst, bioswales and rain gardens are found in quadrant IV and I, respectively. When compared to the constructed wetland, an increase in the economic impacts is found without any influence on the eco-efficiency of the overall placement on eco-efficiency matrix. The maintenance phase contributes more to environmental impacts than the construction, whereas the life cycle cost analysis shows the opposite. [Display omitted] • Life cycle impacts, life cycle cost, and eco-efficiency is assessed for four Low Impact Developments (LIDs). • Box planter and naturally occurring wetland have significantly lower impacts than rain gardens. • The maintenance phase contributes more to environmental impacts than the construction phase. • The cost for construction is higher than maintenance phase. [ABSTRACT FROM AUTHOR]

Water is a finite resource. Increasing population, rapid urbanization, and climate change incidents are continuously adding pressure on freshwater supplies. Overcoming these issues require change in current urban water management (UWM) strategy. In this study, a conceptual model of One Water Community has been developed that aims to reduce potable water use (R PWU) using One Water Approach (OWA). Based on OWA's six guiding principles, five interventions (i.e., control factors) and sixteen parameters have been identified. Each parameter is simulated twice by running 10,000 iterations to calculate a percentage reduction of potable water use at 90th, 50th, and 10th percentiles. A Taguchi-based optimization method has been used to determine the optimum combination of parameters from each of the five control factors [water saving appliances (WSA), reclaimed water use (RWU), resource recovery (RR), low impact development (LID), and good governance (GG)]. L 16 orthogonal array experimental design plan was considered in conducting the trials. ANOVA analysis showed that RWU, RR, and WSA were the most influential factors on R PWU performance at 90th, 50th, and 10th percentiles. Validation tests validated the model by predicting the S/N ratio at the optimum condition. The findings indicated that water sense labeled urinals, reclaimed water for agriculture purposes, emissions reductions from treatment plants, bioswales, and increased public awareness were the most optimum parameters in achieving the highest potable water reduction potential at the 90th percentile. The developed model will open new avenues in UWM, which will assist decision-makers in building sustainable, reliable, and resilient urban water systems. [Display omitted] • One Water Approach concept is capable to bring a change in urban water management. • A conceptual model of One Water Community was developed based on six principles. • Five factors and sixteen parameters were identified to reduce potable water use. • A Taguchi based technique was employed to determine optimum parameters combination. • Experimental values were greater than predicted values to justify the optimum condition established in the study. [ABSTRACT FROM AUTHOR]

Abstract Household energy consumption and carbon footprints change with household characteristics such as type of residence, energy system performance, vehicle performance, and users' behavioral patterns. Accordingly, alternative energy technologies, such as clean electricity, hydrogen fuel cells, and energy efficient interventions, are being adopted in many parts of the world to reduce the residential, industrial, and transportation emissions. This paper presents a comprehensive research framework to identify the most desirable building retrofits and incentive schemes for Canadian households. Globally available incentive policies for low-emission vehicles and locally available retrofit options for single-family detached houses were identified during this study. A decision support tool based on life cycle thinking was developed to assess economic parameters, such as capital investment and annualized consumer cost, and environmental parameters such as greenhouse gas emissions. In order to rank and select the most desirable building retrofit, the TOPSIS ranking method was used. The linear programing graphical method was used to select the best incentive policy for low-emission vehicles. Finally, scenario analysis was used to compare different households based on regional economic and environmental characteristics. Provinces which have low-emission electricity grids such as Manitoba, British Columbia, and Quebec can primarily focus on incentives for electrified transportation. Additionally, the incentives for retrofits such as greener appliances and heating, ventilation, and air conditioning systems would also significantly reduce building carbon footprint. Conventional residential buildings with fossil fuel vehicles are more desirable for provinces like Saskatchewan, Alberta, and Nova Scotia which have high-emission electricity grids. Based on the outcomes of this research, a scientific incentive planning and management approach considering regional economic and environmental characteristics was introduced. Highlights • Life cycle thinking-based economic factors and operating emissions of single-detached household were analyzed. • Possible retrofit incentives and retrofit combinations were ranked based on regional economic and environmental factors. • Regions with low emission electric grids can primarily focus on incentives for electrified transportation system. • Conventional households and fossil-vehicles are desired for the areas with higher emission factor electric grid. [ABSTRACT FROM AUTHOR]

A fuzzy-based indexing approach was developed for the management of hydraulic fracturing chemical additives. The environmental and human health hazards of an additive are converted to hazard indices using an indexing system. To account for uncertainties, a fuzzy-based approach is adopted based on fuzzy inference and fuzzy clustering analysis to assess the risk potential of different additives for informed chemical management decision making. The assessment of the randomly selected additives showed that this fuzzy-based indexing approach gave different chemical hazard assessment results for about 30% of the assessed additives. This shows that accounting for uncertainties using this methodology can lead to better informed chemical management decision making. The hazard assessment results also indicate that based on current indexing methodology more than half of the additives permitted for use in hydraulic fracturing operations are considered moderate environmental and human health hazards. However, based on the new fuzzy-based approach the majority (80%) of the additives were identified as low and very low risk potential due to their low use frequencies. [ABSTRACT FROM AUTHOR]

During the recent past, the individual responsibility of climate change mitigation has been acknowledged by the society at large. Energy planning is pivotal in mitigating GHG emissions and adopting climate resilient strategies. However, community level energy planning has been overlooked in the urban development planning and the approval process. Many energy and emission reduction approaches are still voluntary for the developers and been pursued on ad-hoc basis. The objective of this study is to propose a systematic framework for renewable energy integration in community development. A scenario-based study was conducted for an upcoming neighbourhood in Okanagan, British Columbia (BC), Canada. Scenarios were assessed based on the life cycle cost (LCC) and GHG emission reduction. The scenarios were then compared based on costs and benefits to key stakeholders. Results of this study revealed that a higher share of renewable sources in the energy mix does not necessarily reduce LCC or GHG emissions. The benefits which can be achieved via incorporating renewables to the regional energy mix varies, depending on the existing energy sources in the mix. Therefore, regional power grid mix influences the feasibility and acceptability of RE integration at a given location. Developers should be aware of the optimal investment level which could be fully or partially recovered by premium home prices. The government should promote this practice via various incentives such as tax credits, grants etc. Findings of this research would mainly inform urban developers in renewable energy planning and local government in formulating climate action policies. [ABSTRACT FROM AUTHOR]

Climate-conscious development is a topic which has received widespread attention. One consequence of this is the prominence of greenhouse gas (GHG) emissions reduction targets set at various administrative levels (i.e. global, national, provincial and local governments). Despite the global interest, current models are incapable of integrating GHG emission reduction into the urban planning. This study presents lessons learned from a climate conscious growth study conducted for a fast-growing municipality in Okanagan, British Columbia, Canada, offering a model for local government target-setting generalizable across networks of communities, leading to significant cumulative GHG reductions at global scale. The study uses the results of engineering-based research to evaluate multiple planning scenarios developed to explore options for the subject municipality’s future urban form and the associated GHG emissions for the target year 2040. Overall municipal GHG emissions for each scenario were simulated in the study considering the residential and transportation emissions projections. The findings indicated that the lowest emissions scenario was the ultra-compact growth model without area structure plan (ASP) allocations. Accordingly, it was concluded that a densified growth strategy with a higher share of multi-unit residential development is technically the best path forward in municipal growth planning to meet climate action targets. Negative public perception of increased densification in urban areas remains an obstacle to the technically best solution. Moreover, per capita basis could be a more feasible approach for GHG emissions target setting. This study’s outcomes are expected to inform public sector institutions and decision makers in setting GHG targets and climate action planning. [ABSTRACT FROM AUTHOR]

The global climate is being heavily affected by greenhouse gas (GHG) emissions, the most significant of which is carbon dioxide (CO 2). According to the Pan-Canadian framework on clean growth and climate change, Canada has set ambitious targets to realize a low carbon future. Amongst the available emission reduction strategies, on-site carbon capture, utilization, and storage (CCUS) is a proven technology capable of abating CO 2 emissions from fossil fuel-based energy systems. However, the viability of CCUS technologies is still uncertain and is subjected to numerous dynamic parameters. This study aims to assess the long-term economic viability of integrating carbon capture technologies into community emission planning. Key decision variables were identified, and the dynamic economic performance of CCUS investments was assessed for academic complexes located in two locations in Canada. A system dynamics model was developed to assess the future costs of carbon capturing projects. The study outcomes showed that CCUS is more feasible in provinces with high reliance on fossil fuel energy sources. Moreover, a significant portion of carbon capture costs is taken by infrastructure. Government policies have a critical role in accelerating the commercialization of CCUS technologies. The findings from this study are geared toward providing useful decision-support tools for policy experts, investors, and utility providers who are responsible for policy and investment decisions. Policymakers and investors will be benefited from the proposed model to develop customized regional policies and make investment decisions by considering dynamic regional aspects. Moreover, the results provide insight into what areas require attention in making CCUS economically viable. • System dynamics modelling can be used to predict carbon capture costs subjected to dynamic parameters. • Emission reduction with carbon capturing may change depending on regional parameters. • Carbon capture costs are sensitive to energy demand, grid composition, and carbon dioxide transport distances for utilization. • Community energy Infrastructure development and climate policies are essential in improving economies of carbon capturing technology. [ABSTRACT FROM AUTHOR]

Passive houses optimize energy gains and losses to attain higher energy efficiencies, comfort levels, and affordability. This article allows attaining a broader understanding of the risks and opportunities of passive technologies and their impacts through a social cost-benefit analysis framework. Time value of money was incorporated to evaluate the net present values (NPV), cost-benefit ratios, and internal rates of return. Five alternative houses consisting of passive and net-zero technologies were compared against a conventional design (traditional model). The base model with renewable energy integrations indicated higher impacts on the cumulative cost-benefits in economic, social, and environmental perspectives. Furthermore, a sensitivity analysis evaluated the effects of independent variables such as the interest rate and energy consumption on the performance metrics. This paper allows users to attain a holistic idea of implementing passive dwellings in a selected region through a social cost-benefit point of view. • A framework to evaluate passive house application for a region was developed. • Economic, social, environmental costs and benefits were considered in the framework. • Socio-environmental factors have a significant impact on the study's performance. • Incorporation of renewable energy provides higher benefits for the alternatives. • Passive houses increase overall benefits and decrease environmental impacts. [ABSTRACT FROM AUTHOR]

The ever-increasing anthropogenic greenhouse gas (GHG) emissions worldwide make it quite challenging to meet country-specific Nationally Determined Contributions (NDC) targets. Therefore, it is evident that the existing emissions abatement measures need to be taken a step further. Internationally Transferred Mitigation Outcomes (ITMOs) are allowed in Article 6.2 of the Paris Agreement as a cooperative approach to achieving NDC goals. There is a potential to create ITMOs between Canada and China by replacing coal use in China with British Columbia (BC)'s liquefied natural gas (LNG) supply. Replacing coal with LNG in energy generation applications is a promising approach to mitigate emissions. With global and national pressures to reduce emissions, China has created a market for LNG imports to cater to its rising natural gas (NG) consumption due to the coal-to-gas source switching strategy. However, the terms under Article 6.2 requires generated ITMOs to ensure environmental integrity, support sustainable development goals, and have a robust accounting system. Therefore, the current study aims to quantify the life cycle environmental outcomes of generating ITMOs by exporting LNG from BC to Chinese end-users while integrating uncertainties and to provide policy recommendations in adherence with the requirements of Article 6.2. Different LNG export scenarios were generated in the study and environmental impacts of each scenario were assessed and compared using a life cycle assessment (LCA) framework developed by the authors. Sensitivity and uncertainty analyses were conducted to understand the impacts created by the data uncertainties in the final result. By replacing conventional coal with NG, approximately 40–45% and 26%–32% emissions reductions can be obtainable for Chinese textile and chemical industries, respectively. The highest emissions reduction of approximately 60% was observed when coal is replaced with NG for district heating. The life cycle emissions (LCE) quantification framework provided in the study provides stakeholders with a systematic approach to determine the total GHG emissions and emissions reduction potential of different LNG export scenarios. [ABSTRACT FROM AUTHOR]

Global climate change is a key concern in today's world, especially with the growth of population and industrial activities. One of the biggest sources of climate change is anthropogenic greenhouse gas emissions. In Canada, buildings are the third largest emitter of greenhouse gases, contributing to 12% of the country's equivalent Carbon dioxide emissions. These emissions have various negative impacts on the planet, which impede the transition towards a cleaner environment and more sustainable communities. Attention has now shifted towards Carbon dioxide reduction in addition to the currently practiced energy efficiency improvements and source switching, which is also important in achieving Canada's 2030 climate action goals. The current study attempts to address the above gap by investigating the feasibility of installing carbon capturing unit at building level, based on the perceptions of building managers in both multi-unit residential buildings and non-residential buildings. A Modified Digital Logic approach was used to identify the key factors that determine the acceptability of the unit, based on experts' input. Six primary criteria were identified to design a questionnaire and structured interviews to evaluate the acceptability of building level carbon capturing unit to stakeholders. The findings indicated that around 50% of non-residential building managers were interested in installing the carbon capturing unit, whereas none of the multi-unit building managers were in favor of the unit installation. The lack of interest is attributed to different factors such as unit scalability, inability to accurately estimate the short and long-term economic benefits, and other alternate plans to reduce carbon dioxide emissions. Specifically, when establishing relationship between cost and unit scalability, 82% of residential unit managers and 50% of non-residential managers opined that the unit should be capable of being upgraded to accommodate a larger area and capture more emissions in order to justify the proposed cost of the unit. The findings provide important insights for policy makers in understanding the acceptability of carbon capturing unit at building level and to further develop and promote this emerging technology in the market. [Display omitted] [ABSTRACT FROM AUTHOR]

Production of high volumes of wastewater by hydraulic fracturing operations is a challenging issue in the unconventional gas industry in North America. A scheduling-based solution is required to optimally manage the produced wastewater. This study develops a novel, hybrid, multi-objective linear programming model to optimize hydraulic fracturing wastewater management alternatives. Minimizing overall wastewater treatment cost, environmental impacts, and undesirable deviations from different goals were simultaneously considered the main objectives of the system. The model used data from a case example operating for 31 weeks, and it determined the volume of wastewater and treated water over all periods. The results indicated that onsite treatment is the best possible alternative for reuse in subsequent fracking, in those weeks in which all constraints were satisfied. Offsite treatment was the second ranking alternative when the volume of wastewater was higher than the capacity of onsite treatment, and deep well injection was the result when no water was needed for subsequent fracking. A sensitivity analysis was conducted by weighting the objectives to express their importance levels. Compared to other objectives, environmental impact had greater effect on the selection of the optimal alternatives over each period. Image 1 • A multi-objective framework was developed based on goal and linear programming. • Objectives were weighted based on different weighting scenarios. • The model can optimally solve hydraulic fracturing wastewater management problems. • The model can be simply updated and applied in water and wastewater management. [ABSTRACT FROM AUTHOR]

The environmental impacts of the mining industry as well as reduction strategies are important issues that have been highlighted as a result of the environmentally-friendly policy of green mining. As part of that policy, this study developed an approach based on a multi-layer artificial neural network and fuzzy cognitive map to predict the vertical and horizontal distribution of blast-induced dust emissions, simultaneously. Hence, a fuzzy cognitive map based on the cause-and-effect analysis concept was first designed to extract inputs' weights. An optimal network with two hidden layers was then implemented to predict the vertical and horizontal dust distributions in a mine close to residential and agricultural areas. The performance evaluation of the approach indicated good results by the R2 of 0.9933 and 0.9267 between the measured and predicted values for the horizontal and vertical distributions, respectively. Furthermore, the predicted and measured outputs over every blasting round were in accordance due to the slight mean absolute and root mean square errors of 0.009 and 0.018, respectively. A sensitivity analysis revealed that all inputs, excluding air humidity on the vertical distribution, had acceptable effects on the dust distribution outputs by the strength of higher than 0.7. Based on a reduction solution that we suggested, one round was blasted by taking water capsules together with stemming material in 40% of the whole blast holes. The results indicated that the maximum horizontal distribution of blast-induced dust was decreased about six times. The approach can be straightforwardly updated and used for other mining cases. • Fuzzy cognitive map and neural network were integrated for dust prediction. • Vertical and horizontal dust distributions were simultaneously predicted. • A real critical case was applied to investigate the capability of approach. • Horizontal dust distribution was highly decreased through the suggested solution. [ABSTRACT FROM AUTHOR]

Planning decentralised community-level hybrid energy systems has emerged as a solution to the various environmental and economic issues associated with conventional centralised energy supply systems. However, the optimal planning of community energy systems is a challenging issue due to the complexities, uncertainties, conflicting objectives, and high computational times in analysis. This study introduces a new multi-objective model based on weighted goal programming and grey pairwise comparison to assess renewable energy-based strategies in the case of net-zero energy communities. The problem was formulated to determine the optimal energy mix based on minimization of life cycle impacts and costs and maximization of renewable contributions and operational energy savings. To this end, binary integer and continues variables were applied on the code developed in a CPLEX environment. A pairwise comparison based on grey numbers was used to find the impacts of the goals in the objective function of the model under uncertainty. In addition to the grey-based weighting scenario, different weighting scenarios were employed to consider the importance of all goals on the system. These weighting scenarios were used to investigate the effects of changing decision priorities on the outcomes and on stakeholder interests at different levels. The developed goal-programming model was applied to the data of a case example and solved based on the weighting scenarios. Results indicated that the model is capable of finding the best possible strategies with the lowest total undesirable deviations from the desired levels of the goals compared to the literature of the decision-making techniques. The integration of maximum renewable energy (RE) supply in the energy mix with the locally available energy resources can deliver considerable benefits in terms of energy supply cost reduction as well as in mitigating life cycle environmental impacts. When environmental goals are prioritized, integrating low emissions RE as much as possible and excluding waste-to-energy technologies makes best sense, while under a pro-economic perspective, solar integration is comparatively discouraged. The findings of the study are expected to assist community developers and other decision makers involved in regional energy planning. The developed method will also be of use for those who are interested in the use of goal programming to solve complex planning issues involving numerous uncertain parameters. • Energy planning involves multiple decision dimensions and requires multi-objective optimization. • Goal programming can be used to reduce computational time in complex optimization problems. • Optimal energy mix in community energy systems change based on decision priorities. • RE integration can deliver life cycle economic and environmental benefits for communities. [ABSTRACT FROM AUTHOR]

Occupant behavior in residential buildings has a direct impact on the effectiveness of energy-saving measures. In order to realize a buildings' carbon mitigation targets, the impact of individual occupancy profiles needs to be integrated with building simulation models. This paper introduces a decision support framework as a potential solution to make energy performance upgrade choices based on different occupancy profiles. This framework has been demonstrated through a case study of two single-family detached homes in Canada, which were highly instrumented with sensors for monitoring energy input and output. The case studies represented two common occupancy profiles-(1) a family of four (consisting of 2 working adults and 2 teenagers); and (2) a retired couple. Firstly, calibrated energy models were developed by using one-year energy use data collected through an intrusive load monitoring technique. Secondly, energy upgrade combinations were considered for each profile and tested for additional investment, payback period and greenhouse gas (GHG) emissions. Lastly, the most suitable combination of energy upgrade for each profile was ranked using a multi-criteria decision-making method (e.g., TOPSIS). Results indicated that the retired couple used more energy than the family of four and required energy upgrades with usually higher payback periods to achieve the same level of GHG emission reduction. The results of this research are timely for energy policymaking and developing best management practices, which need to be implemented along with the deployment of more stringent building standards and codes. • A scenario-based framework was developed for residential homes energy upgrades. • It considers occupant behavior and preference in selecting energy upgrades. • Field data is used to represent energy use of a family of four and a stay-at-home retired couple. • Energy upgrades are same under pro-economic choices for two profiles. • Energy upgrades vary under pro-environmental scenarios for two profiles. [ABSTRACT FROM AUTHOR]

Disinfection by-products (DBPs) in public indoor swimming pools (ISP) are a major human health risk concern. Various DBPs control strategies have been developed as an integral part of ISP management; however, these strategies are associated with different energy and resource consumption and environmental impacts. In this study, a process-based life cycle assessment (P-LCA) framework is developed for determining the environmental impacts of DBPs control strategies in ISP management. The developed framework requires ISP operation information such as energy, water, and chemical use, and concentration data under each DBPs control strategy as inputs. The ReCipe2016 midpoint method is used to process the inputs and quantify the lifecycle impacts in terms of three categories: energy, water and chemicals. Based on the outputs, the best strategy is selected using the TOPSIS method. The developed framework is applied to an ISP located in Vancouver (Canada) to evaluate seven DBPs control strategies associated with various air circulation rates. The DBPs concentration data were sourced from a previous sampling campaign. The results show that energy use is the main contributor (87–94%) to the total environmental impacts as compared to chemical and water use (6–13%). Among the tested strategies, reduction of fan speed can yield maximum environmental benefits without compromising the DBPs control performance. On the other hand, supply of 100% fresh air at normal fan speeds results in higher environmental impacts compared to a baseline case despite the lower DBPs releases. The proposed P-LCA framework can facilitate pool operators in selecting low impact DBPs control strategies for sustainable ISP management. • Disinfection by-product control strategies were identified for indoor swimming pools. • A process-based lifecycle assessment framework was proposed for the strategies. • The developed framework was applied to an indoor swimming pool as a case study. • The highest impacts are associated with energy use for pool heating and ventilation. [ABSTRACT FROM AUTHOR]

A human health risk-based life cycle assessment (LCA) framework was developed for selecting low-impact water treatment systems with a focus on heavy metal(loids) removal. The framework comprises three phases, including pilot-scale water treatment, human health risk assessment (HRA), and LCA. The application of the framework was demonstrated by a case study. Two water treatment systems employing ozonation-greensand-ferric hydroxide-based sorbent (OGF) and Birm-ferric hydroxide-based sorbent (BF) processes were used to reduce arsenic and manganese concentrations in the source water of a small municipality in southwestern Canada. The heavy metal(loids) concentration as well as material and energy use data of the two systems were collected to perform HRA and LCA. The results showed that both systems can reduce arsenic and manganese concentrations; however, the removal efficiencies of OGF and BF processes decreased with the increase of treatment volume. At a constant inflow rate, the ferric hydroxide-based sorbent needed to be replaced every 31 and 25 days in the OGF and BF processes, respectively, to ensure that arsenic concentration in the effluent would not pose any significant human health risk. The LCA results indicated that the system using the OGF process generated lower life cycle environmental impacts than the system using the BF process throughout ten years' operation. It was also found that the arsenic removal process was the largest impact contributor in both systems. The manufacturing of ferric hydroxide-based sorbent and disposal of arsenic-contaminated treatment waste accounted for the highest impact in water treatment. Image 1 • A health risk-based LCA framework is proposed for assessing water treatment systems. • Two water treatment systems designed for arsenic and manganese removal are assessed. • Human health risk assessment determines acceptable adsorbent replacement frequency. • System using ozonation-greensand-ferric oxyhydroxide treatment shows lower impacts. • Arsenic removal process generates the highest life cycle environmental impacts. [ABSTRACT FROM AUTHOR]

This study presents a comparative life cycle assessment (LCA) of traditional and emerging treatment approaches for hazardous refinery oily sludge handling. Two traditional oily sludge disposal approaches, including incineration and landfilling, and two emerging energy recovery approaches, including solvent extraction and pyrolysis, were investigated. Life cycle inventories listing all energy and material flows were established for the two emerging treatment approaches, and the life cycle environmental impacts were assessed by following the International Organization for Standardization (ISO) 14040 procedure. The TRACI 2.1 method and Ecoinvent 3 database were used in the LCA. The results show that the two emerging energy recovery approaches only account for <10% of the total impacts posed by the traditional alternatives. Traditional oily sludge treatment approaches are generally associated with relatively high global warming potential, ecotoxicity, and adverse human health effects. Solvent extraction has the lowest total effect on the environment, and the main adverse effects are related to ecotoxicity and fossil fuel depletion. In solvent extraction treatment, vacuum distillation and combustion of recovered oil account for the main impacts. In pyrolysis treatment, processes such as drying, pyrolysis, and combustion of pyrolysis products are the main contributors to the total impact. The energy recovery processes used in the two emerging approaches can significantly offset the total adverse impacts. The two energy recovery approaches have great potential to be used for low-impact oily sludge treatment. [ABSTRACT FROM AUTHOR]

High-tech minerals (HTMs) used for manufacturing mobile phones are indispensable raw materials for emerging Chinese national strategic industries. China is the world's largest mobile phone market, and increasing amounts of HTMs are found in the country's excessive mobile phone waste. Thus, it is important to investigate the life cycle cost (LCC) of recycling HTMs from waste mobile phones. In this study, material flow analysis (MFA) and LCC assessment were conducted to analyze the recycling of waste mobile phones and the contained HTMs. The LCCs of recycling two types of mobile phones, i.e., feature phones and smartphones, were investigated. The results show that the LCCs of recycling one waste feature phone and one waste smartphone are approximately US$ 2.34 and US$ 6.60, respectively. The LCCs of extracting HTMs from one waste feature phone are US$ 6.035 for 1 g of cobalt and US$ 0.014 for 1 g of palladium, while the LCCs of extracting 1 g of cobalt, palladium, antimony, beryllium, neodymium, praseodymium and platinum from one waste smartphone are US$ 10.106, US$ 0.024, US$ 0.135, US$ 0.005, US$ 0.08, US$ 0.016 and US$ 0.006, respectively. Based on the LCC results, constructive suggestions and policy implications are provided for future mobile phone management in China. • Life cycle cost of recycling two types of mobile phones, simply feature phones and smartphones, were investigated. • Life cycle cost of extracting various high-tech minerals from waste mobile phones were analyzed. • Constructive suggestions and policy implications are provided for future mobile phone management in China. [ABSTRACT FROM AUTHOR]

The building sector accounts for 40% of the energy use and one-third of the greenhouse gas (GHG) emissions globally. Buildings deteriorate with age, which leads to a decrease in their energy performance. Therefore, it is significant to improve the energy performance of aging building block although it is challenging. The two main decision paths for municipalities are renovation and reconstruction. This study investigated the above options for the older housing stock in a densely populated urban centre in British Columbia, Canada. A scenario-based analysis approach was taken to evaluate the life cycle GHG emissions of six different renovation and reconstruction scenarios. The total life cycle emissions were calculated for each scenario including the embodied and operational emission, and the emissions from building construction and maintenance. A BIM-LCA combined approach was used to assess the embodied GHG emissions with the SimaPro software. HOT2000 software was used to model the operational GHG emissions. The results show that in the reconstruction scenarios, around 40% of the emissions are from the material manufacturing stage. The embodied emissions generated from the reconstruction scenarios are 5–6 times higher than the renovation scenarios. The life cycle GHG emissions of the existing house can be reduced by applying renovations, with the emissions saving gradually increasing with the level of retrofitting. The passive house reconstruction scenario delivers the greatest benefit in terms of life cycle emissions reduction compared to all other scenarios. In terms of the GHG emission intensity per unit area, the newly-built houses in scenarios 5 and 6 also have lower life cycle GHG emission per square meter than the renovated existing houses in scenario 1–4 after 15 and 10 years to breakeven respectively. Based on this, it can be concluded that when considering the older existing building stock, a careful weighing of options must take place before making the decision on replacing them with new construction. However, it is also important to consider the economic and social aspects before making decisions to renovate or replace existing houses. The study outcomes will support city planners and urban development planners to make decisions on BC aging building stock development, especially in high population density neighbourhoods. • Renovation/replacement decision of aging building stock should consider lifecycle impacts. • A scenario-based approach was taken to assess overall GHG emissions of each decision for residential buildings. • Operational GHG emissions reduce with the extent of renovation while increase in embodied emissions. • The life cycle emissions of moderate to extensive renovations have similar outputs as the code-constructed new buildings. • Replacing older houses with new passive construction can significantly reduce life cycle emissions. [ABSTRACT FROM AUTHOR]

Recent studies have shown that Canada will not achieve its 2030 emission reduction targets outlined in the Paris Agreement. Canadian energy decision makers are now at a crossroad between making sound fiscal decisions and ramping up efforts to meet emission reduction commitments. Approximately 195,000 people are living in off-grid Canadian communities, with most of these communities relying on fossil-fuel based energy generation. Hybrid renewable energy systems provide a novel solution to address the high costs of off-grid energy and Canada's emission reduction targets. To address the competing stakeholder priorities in off-grid energy planning (e.g., economic, environmental, and system performance), the authors of this paper employed a generalizable combinatorial-based alternative ranking method. Alternative energy technology combinations were simulated to calculate key performance indicator values. The framework allows decision makers to identify the most feasible energy system based on their priorities. A case study was performed with the developed framework for a small off-grid community in British Columbia, Canada. The results show that feasibility of energy system configurations vary greatly based on differing decision-making priorities. The case study also confirmed that hybrid renewable energy systems have better environmental performance compared to their fossil fuel counter parts, but at a significantly higher cost. The study further confirms that the balance between environmental and economic performance of off-grid energy systems can be improved through proper component sizing, management practices, and the integration of energy storage. • Life cycle impacts need to be considered in off-grid hybrid renewable energy systems planning. • Hybrid renewable energy systems incur lower environmental impacts at higher costs. • Combining fossil fuel generators and battery banks reduces emissions at a lower cost. • Decision makers' priorities has a high impact in the ranking of energy system configurations. • The developed method accounts for different priorities in energy system feasibility assessment. [ABSTRACT FROM AUTHOR]