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• Proposing a multi-model robust dynamic output feedback damping controller for the GCSC. • Investigating a two-step LMI approach for solving BMI optimization problem. • A multi-objective H 2 / H ∞ synthesis with regional pole-placement. • Power system operational uncertainties considering variations in operating conditions are represented as multi-model. In the recent decade, the power network has experienced a remarkable energy transition due to the large-scale integration of wind energy resources, especially converter-interfaced modern wind turbines. The increasing/decreasing wind penetration, on the other hand, unexpectedly affects the low frequency oscillations of the modern power grid. In this context, the proposed work adopts a multi-model multi-objective robust control framework to design a supplementary damping controller for the gate-controlled series capacitor (GCSC) to stabilize the hybrid power system with a permanent magnet synchronous generator (PMSG)-based off-shore wind farm (OSWF) and a doubly-fed induction generator (DFIG)-based onshore wind farm (ONWF). A bilinear matrix inequality (BMI) optimization problem, formulated as multi-objective synthesis considering H 2 / H ∞ performance along with pre-defined pole placement, is presented for the GCSC control design, which is solved by a two-step linear matrix inequality (LMI) approach. In addition, all LMI constraints are constructed based on the multi-model control framework to incorporate multiple operating conditions. Afterward, the significant improvement in the damping characteristics of the closed-loop system, covering a wide operating range, is confirmed using eigenvalue analysis. The effectiveness of the scheme is validated using two case studies based on the hybrid power system, subject to various disturbances and uncertainties. The simulation results show the robustness and higher damping performance of the proposed multi-model strategy, compared to a conventional and a robust damping controller, for mitigating power system oscillations alongside voltage fluctuations of the wind farms. [ABSTRACT FROM AUTHOR]

Environmental impact assessment of energy generation processes is essential to evaluate their contributions toward the global carbon footprint. Even though hydrogen is a non-carbonaceous energy source, the pathways undertaken for its production can have harmful environmental implications. Thus, this study focuses on investigating the exergoenvironmental performances of the copper-chlorine, iron-chlorine, and magnesium-chlorine thermochemical hydrogen generation processes. This study also performs a comparative exergoenvironmental analysis of the three processes. The performances of the various processes are examined based on of the environmental impact rates of exergy destruction, component-related environmental impact rates, cumulative environmental impact rates, and exergoenvironmental factors. The global warming potentials of the thermochemical cycles are also evaluated and compared for various electricity sources to obtain hydrogen. The modeling and simulation of each process are performed using Aspen-plus by considering various heat recovery approaches for thermal management. The results suggest that the environmental impact rates of exergy destruction are relatively much higher compared to the environmental impact rates associated with the components for all processes. Furthermore, the hydrolysis step yields the highest component-associated environment impact rate for all thermochemical cycles considered (Fe–Cl: 3497 mPts/h, Cu–Cl: 1997 mPt/h, and Mg–Cl: 910 mPts/h). Moreover, the magnesium-chlorine cycle results in the highest environmental impact rate of exergy destruction (650,328 mPts/h) while the iron-chlorine cycle has the highest component-related environmental impact rate (5219 mPts/h) among the three cycles. In addition, the global warming potential of the magnesium-chlorine cycle is relatively higher compared to the copper-chlorine cycle for several electricity sources. [Display omitted] • An exergoenvironmental analyses of three thermochemical cycles is performed. • Each cycle is incorporated with thermal management schemes for higher efficiencies. • Industrial waste flue gases are considered as a heat source for hydrolysis reaction. • A hydrogen production capacity of 668 kg/h is considered for each cycle. • A comparison of global warming potential for various electricity sources is made. [ABSTRACT FROM AUTHOR]

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]

Acid rock drainage (ARD) is a major environmental problem that poses significant environmental risks during and after mining activities. A new methodology for environmental risk assessment based on probability bounds and a geochemical speciation model (PHREEQC) is presented. The methodology provides conservative and non-conservative ways of estimating risk of heavy metals posed to selected endpoints probabilistically, while propagating data and parameter uncertainties throughout the risk assessment steps. The methodology is demonstrated at a minesite located in British Columbia, Canada. The result of the methodology for the case study minesite shows the fate-and-transport of heavy metals is well simulated in the mine environment. In addition, the results of risk characterization for the case study show that there is risk due to transport of heavy metals into the environment. [ABSTRACT FROM AUTHOR]

This paper deals with online water quality monitoring in distribution networks based on surrogate water quality parameters (WQPs). The present strategy is based on multi-level information fusion using hierarchical belief rule-based (BRB) systems. Networked fuzzy belief rule-based (NF-BRB) and high-level BRB systems are introduced for information fusion at the feature level. Primary and secondary features are extracted from online WQP signals. Primary features are analyzed using the NF-BRB system that is built through knowledge elicitation from experts. Secondary features are interpreted through the high-level BRB system that employs a fuzzy partitioning on the feature sets and a hybrid learning strategy for its rule base construction. Finally, the dynamic fuzzy evidential fusion is introduced to aggregate the local and spatial assessments in each analysis window. As an important contribution of this paper, we propose a new validation method for event detection in the water distribution network (WDN) based on adaptive projection of the signal patterns attributed to anomaly events, obtained through contamination experiments in a pilot facility, to the real WQP signals measured across the WDN. Single and composite contamination events based on several biological and chemical contaminants are simulated to evaluate the performance of the proposed framework in event detection. The proposed multi-level information fusion framework obtains a high detection rate and a reduced number of false negative and positive results. [ABSTRACT FROM AUTHOR]

Acid rock drainage (ARD) is a major pollution problem globally that has adversely impacted the environment. Identification and quantification of uncertainties are integral parts of ARD assessment and risk mitigation, however previous studies on predicting ARD drainage chemistry have not fully addressed issues of uncertainties. In this study, artificial neural networks (ANN) and support vector machine (SVM) are used for the prediction of ARD drainage chemistry and their predictive uncertainties are quantified using probability bounds analysis. Furthermore, the predictions of ANN and SVM are integrated using four aggregation methods to improve their individual predictions. The results of this study showed that ANN performed better than SVM in enveloping the observed concentrations. In addition, integrating the prediction of ANN and SVM using the aggregation methods improved the predictions of individual techniques. [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]

Abstract: Protecting drinking source water quality is a critical step in ensuring a safe supply of drinking water. Increasingly, drinking source water protection programs rely on the active participation of various stakeholders with differing degrees of water science knowledge. A drinking source water quality index presents a potential communication and analysis tool to facilitate cooperation between diverse interest groups as well as represent composite water quality. We tested the effectiveness of the Canadian Council of Ministers of the Environment Water Quality Index (CCME WQI) in capturing expert assessments of drinking water quality. In cooperation with a panel of drinking water quality experts we identified a core set of parameters to reflect common source water concerns. Drinking source water target values were drafted for use in the index corresponding to two basic treatment levels. Index scores calculated using the core parameter set and associated source water target values were strongly correlated with expert assessments of water quality. We recommend a modified index calculation procedure to accommodate parameters measured at different frequencies within any particular study period. The resulting drinking source water CCME WQI provides a valuable means of monitoring, communicating, and understanding surface source water quality. [Copyright &y& Elsevier]

Abstract: Performing risk analysis can be a challenging task for complex systems due to lack of data and insufficient understanding of the failure mechanisms. A semi quantitative approach that can utilize imprecise information, uncertain data and domain experts’ knowledge can be an effective way to perform risk analysis for complex systems. Though the definition of risk varies considerably across disciplines, it is a well accepted notion to use a composition of likelihood of system failure and the associated consequences (severity of loss). A complex system consists of various components, where these two elements of risk for each component can be linguistically described by the domain experts. The proposed linguistic approach is based on fuzzy set theory and Dempster–Shafer theory of evidence, where the later has been used to combine the risk of components to determine the system risk. The proposed risk analysis approach is demonstrated through a numerical example. [Copyright &y& Elsevier]

Abstract: The potential for generation of disinfection byproducts (DBPs) in swimming pools is high due to the concentrations of chlorine required to maintain adequate disinfection, and the presence of organics introduced by the swimmers. Health Canada set guidelines for trihalomethanes (THMs) in drinking water; however, no such guideline exists for swimming pool waters. Exposure occurs through ingestion, inhalation and dermal contact in swimming pools. In this research, a multimedia model is developed to evaluate exposure concentrations of THMs in the air and water of an indoor swimming pool. THM water concentration data were obtained from 15 indoor swimming pool facilities in Quebec (Canada). A level III fugacity model is used to estimate inhalation, dermal contact and ingestion exposure doses. The results of the proposed model will be useful to perform a human health risk assessment and develop risk management strategies including developing health-based guidelines for disinfection practices and the design of ventilation system for indoor swimming pools. [Copyright &y& Elsevier]

Abstract: In recent years, numerous attempts have been made to reduce the global environmental and associated socio-economic impacts of construction activities to achieve sustainable development goals. A sustainable system or activity refers to an eco-friendly, cost effective and socio-politically viable solution. This paper utilizes triple-bottom-line (TBL) sustainability criteria for the selection of a sustainable flooring system in Tehran (Iran). Three types of block joisted flooring systems – concrete, clay, and expanded polystyrene (EPS) blocks – have been investigated using life cycle analysis (LCA). Proposed approach provides a comprehensive evaluation system based on TBL criteria that are further divided into thirteen sub-criteria. It includes: (1) Environmental concerns (resource depletion, waste and emissions, waste management, climate change, environmental risk, embodied energy and energy loss); (2) Economic concerns (material cost, construction cost, and occupation and maintenance cost); and (3) Socio-political issues (social acceptance, vulnerability of area, and building weight). Analytical hierarchy process (AHP) is used as a multi-criteria decision making technique that helps to aggregate the impacts of proposed (sub)criteria into a sustainability index (SI) through a five-level hierarchical structure. Integration of AHP and LCA provides a framework for robust decision making that is consistent with sustainable construction practices. A detailed analysis shows that the EPS block is the most sustainable solution for block joisted flooring system in Tehran. [ABSTRACT FROM AUTHOR]

Abstract: The main objective of this study is to develop a methodology that integrates indicators for performance assessment of small drinking water utilities. The investigation entails 10 water utilities in the Province of Québec (Canada) that use surface water or groundwater under the direct influence of runoff, and apply chlorination as the only treatment before distribution. All 10 water utilities were sampled five times during different months and a total of 50 data sets were collected, which were divided into two groups – training and validation data sets. The assessment of each water utility was done on an arbitrary normalized scale of being ‘problematic’ over a scale of [0,1], where zero mean fully non-problematic and vice versa. The performance indicators consist of source water, treatment, infrastructure, operational, and maintenance characteristics of utilities that are aggregated using ordered weighted averaging (OWA) operators. The major thrust behind selecting the OWA operator for aggregation of multi-criteria is its capability to encompass a range of operators bounded between minimum and maximum. The small utility performance indicators developed suggest that it is feasible to combine information operational, infrastructure, and maintenance characteristics to establish utility performance. The findings of this study is useful to government bodies in terms of achieving a better understanding and assessment of small utilities’ specific infrastructure needs and subsequent allocation of appropriate resources. [Copyright &y& Elsevier]

Abstract: Sustainable development and environmental protection require green products, processes, and waste management strategies. The selection and design of green and clean processes and products involve handling a huge set of data related to the environment, economics and technologies. Therefore, it is essential to employ a comprehensive technique to guide decision-making under uncertainty that can incorporate these factors. The paper presents decision-making under uncertainty based on life cycle analysis and considering environmental, technological, and economical drivers in the analysis. The methodology, GreenPro-1, is applicable at any stage of a process design and can be used to evaluate the environmental burdens of a product or a process throughout its life cycle, and to identify and assess opportunities to make improvements. A weighting scheme is used to integrate various criteria and policies so that a most appropriate alternative can be selected. The GreenPro-1 methodology is applied to a case study for offshore produced water management. In the first stage, 14 best available technologies (BAT) for treatment of produced water are evaluated individually using cradle-to-gate life cycle analysis. In the second stage, seven treatment strategies are developed from BAT and are further investigated. A treatment strategy that combines a hydrocyclone and produced water re-injection proved to be the best system among selected strategies. The combination of hydrocyclone and adsorption was found to be the next best treatment strategy. Two other noteworthy strategies were membrane and centrifuge combination, and down-hole separation and injection. [Copyright &y& Elsevier]

Abstract: Interpreting water quality data routinely generated for control and monitoring purposes in water distribution systems is a complicated task for utility managers. In fact, data for diverse water quality indicators (physico-chemical and microbiological) are generated at different times and at different locations in the distribution system. To simplify and improve the understanding and the interpretation of water quality, methodologies for aggregation and fusion of data must be developed. In this paper, the Dempster–Shafer theory also called theory of evidence is introduced as a potential methodology for interpreting water quality data. The conceptual basis of this methodology and the process for its implementation are presented by two applications. The first application deals with the interpretation of spatial water quality data fusion, while the second application deals with the development of water quality index based on key monitored indicators. Based on the obtained results, the authors discuss the potential contribution of theory of evidence as a decision-making tool for water quality management. [Copyright &y& Elsevier]

The objective of this study was to develop a methodology for estimating aggregative risk of various environmental activities, pollution sources and routes in a given process. The rate of risk is defined by a product of grade of risk (r, magnitude) and grade of importance (i, intensity). Both factors r and i are expressed by an 11-level qualitative scale which are defined by triangular fuzzy numbers to capture the vagueness in the linguistic variables. A three-stage hierarchical structure aggregative risk model was developed for grouping of risk items. For this grouping an analytical hierarchy process was used. A sensitivity analysis was also performed to verify the effect of weighting schemes on the assessment of a final aggregative risk. The developed methodology is applied to a case study of offshore drilling waste for evaluating various discharge scenarios. [Copyright &y& Elsevier]

Offshore petroleum drilling wastes contain toxic substances that are potentially harmful to the marine ecosystem. Despite environmentally benign characteristics, wastes associated with synthetic-based fluids still contain a certain amount of pollutants due to contamination with formation oil and the presence of trace heavy metals in barite, which may pose risk when discharged into the marine environment. A framework is presented here for a decision support system for the selection of the best drilling waste discharge option. Uncertainties in the quantification of risk, cost and technical feasibility are expressed by fuzzy numbers. An analytical hierarchy process with a technique called fuzzy synthetic evaluation is employed to determine the best management alternative (discharge scenario). [Copyright &y& Elsevier]

This paper proposes a method using probabilistic risk analysis for application to corrosion associated failures in grey cast iron water mains. External corrosion reduces the capacity of the pipeline to resist stresses. When external stresses exceed the residual ultimate strength, pipe breakage becomes imminent, and the overall reliability of a water distribution network is reduced. Modelling stresses and external corrosion acting on a pipe involves uncertainties inherent in the mechanistic/statistical models and their input parameters. Monte Carlo (MC) simulations were used to perform the probabilistic analysis. The reduction in the factor of safety (FOS) of water mains over time was computed, with a failure defined as a situation in which FOS becomes smaller than 1. The MC simulations yielded an empirical probability density function of time to failure, to which a lognormal distribution was fitted leading to the derivation of a failure hazard function. A sensitivity analysis revealed that the contribution of corrosion parameters to the variability of time to failure was more significant than the combined contributions of all other parameters. Areas where more research is needed are identified. [Copyright &y& Elsevier]

The main objective of this study is to evaluate and predict the performance of slow sand filters used for wastewater treatment. The uncertainties in the control parameters and processes require fuzzy sets to be used when modelling system performance. Fuzzy logic if–then rules were used to build a model for the removal efficiency (total coliforms) of slow sand filters. The data were collected from three pilot-scale slow sand filters at the Alkhobar (Saudi Arabia) wastewater treatment plant. The removal efficiency of filters was modelled using three input control parameters—filtration rate, sand bed depth and grain size. Based on available data, fuzzy logic if–then rules were established. The fuzzy rule-based model was validated using experimental data of three case studies reported in the literature. The results were also compared with a multiple regression model. A possibilistic risk analysis was performed using optimal removal efficiency of the slow sand filters. The risk is estimated with respect to non-compliance of unrestricted agricultural reuse standards (100 total coliform/100 ml). In addition to slow sand filters, post- or pre-chlorination of wastewater is recommended to improve wastewater quality for conforming agricultural reuse standards. [Copyright &y& Elsevier]

Disinfection for drinking water reduces the risk of pathogenic infection but may pose chemical threat to human health due to disinfection residues and their by-products (DBPs) when the organic and inorganic precursors are present in water. More than 250 DBPs have been identified, but the behavioural profile of only approximately 20 DBPs are adequately known. In the last 2 decades, many modelling attempts have been made to predict the occurrence of DBPs in drinking water. Models have been developed based on data generated in laboratory-scaled and field-scaled investigations. The objective of this paper is to review DBPs predictive models, identify their advantages and limitations, and examine their potential applications as decision-making tools for water treatment analysis, epidemiological studies and regulatory concerns. The paper concludes with a discussion about the future research needs in this area. [Copyright &y& Elsevier]

Toxaphene concentration in Lake Superior is increasing despite a complete ban on its usage in North America. It is speculated that it is carried through long-range transport mechanisms from the southern US fields to Lake Superior. A mathematical fate model is used to estimate the toxaphene concentration by incorporating plankton, benthos, sculpin, smelt, alewife and trout in the food web. Planktons and benthos are assumed to be in equilibrium with water and sediments, respectively. Monte Carlo (MC) simulations using Latin Hypercube Sampling (LHS) are performed to estimate toxaphene concentration and its associated uncertainties in the food web. The ecological risk is characterized based on toxaphene concentration calculated in trout tissues. The maximum acceptable toxicant concentration (MATC) is estimated from an acceptable risk of growth inhibition in trout. The one hit model is used for risk characterization and a cumulative distribution function (CDF) of risk is developed. The analysis shows a median value of risk of growth inhibition in trout is below 6%. [Copyright &y& Elsevier]

In recent years, significant attention and emphasis has been given to cleaner and greener technologies in processes and product manufacturing. This is recognized as a key element in pollution prevention (P2) and development of sustainable strategies. Life cycle assessment (LCA) is a systematic approach that enables implementation of cleaner and greener product and process concepts in industry. In recent times substantial progress has been made in the use of LCA for product evaluation and selection. However, its use in cleaner and greener process design and decision-making has not been explored to a great extent.Process design and decision-making are challenging activities that involve trade-off of conflicting objectives, namely costs, technical feasibility and environmental impacts. These conflicting objectives can be analysed at the early design and decision-making stage by considering the full life cycle of a process or a product. A cleaner and greener process is the one that is cost optimal, technically feasible, and environmentally benign. To obtain these results LCA requires various tools and techniques in a systematic methodology. This paper proposes a holistic and integrated methodology GreenPro-I for process/product design by combining the traditional LCA approach with multi-criteria decision-making methods. This methodology is simple and applicable at the early design stage and is more robust against uncertainty in the data. Application of the methodology has been demonstrated in the paper through a urea production case study. [Copyright &y& Elsevier]

Process operation is the most hazardous activity next to the transportation and drilling operation on an offshore oil and gas (OOG) platform. Past experiences of onshore and offshore oil and gas activities have revealed that a small mis-happening in the process operation might escalate to a catastrophe. This is of especial concern in the OOG platform due to the limited space and compact geometry of the process area, less ventilation, and difficult escape routes. On an OOG platform, each extra control measure, which is implemented, not only occupies space on the platform and increases congestion but also adds extra load to the platform.Eventualities in the OOG platform process operation can be avoided through incorporating the appropriate control measures at the early design stage. In this paper, the authors describe a methodology for risk-based process safety decision making for OOG activities. The methodology is applied to various offshore process units, that is, the compressor, separators, flash drum and driers of an OOG platform. Based on the risk potential, appropriate safety measures are designed for each unit. This paper also illustrates that implementation of the designed safety measures reduces the high Fatal accident rate (FAR) values to an acceptable level. [Copyright &y& Elsevier]

Transportation is an economic sector that contributes significantly to global warming due to its high consumption of fossil fuels, and sustainably produced hydrogen is a major contender for an alternative clean energy source. Public transit is vital for environmental sustainability via reducing individual vehicle usage and traffic congestion, and the prospect of powering buses using hydrogen fuel has been extensively studied lately. This paper seeks to comprehensively review the current status of research on hydrogen-powered buses considering triple bottom line sustainability perspectives. A brief technical overview of prospective environmentally benign hydrogen production processes has been presented. Technological, economic, and environmental findings and research trends seen in recent analyses on hydrogen-powered buses have been summarized, along with the status quo of global hydrogen refuelling stations. Identified focal points for future studies include performance enhancements, refuelling infrastructure propagation, and policy formulation. The conclusions derived from this review will benefit the accelerated deployment of hydrogen-fuelled public transit fleets. • Environmentally benign hydrogen production is reviewed techno-economically. • The prospects of using hydrogen for public bus transport are discussed thoroughly. • Blue and green hydrogen production are likely to coexist in the hydrogen economy. • Costs and energy consumption of hydrogen-powered buses need improvement. • Refuelling facility deployment and public awareness of safety should be enhanced. [ABSTRACT FROM AUTHOR]

Financial Incentives (FIs) for green buildings are a major component of energy policy planning and play a vital role in the promotion of sustainable development and carbon mitigation strategies. Despite the presence of numerous FIs in Canada, there is still a lack of understanding on their distribution and effectiveness. This review first investigates the FIs available for residential and commercial buildings in Canada, and then performs a comprehensive review of studies related to FIs' effectiveness evaluation. It is found that FIs for buildings in Canada can be distributed into four categories: tax, loans, grants, and rebates. Among these, rebates from utility providers are the most common and are administered in all provinces. In addition to these, special incentives are available for three end-users (low-income, aboriginal people, landlords and tenants) and for three types of buildings (heritage, non-profit and energy rated). A clear contrast is observed on FIs offered in three regulatory regimes (Federal, provincial and municipal). Four provinces (Alberta, British Columbia, Ontario and Quebec) are leading in green building efforts. The in-depth literature review was also used to develop an understanding on the criteria used in effectiveness evaluation and the factors impacting effectiveness. Based on the findings of different studies on FIs effectiveness, a generic approach for evaluation of FIs is proposed that can help in deploying successful FIs programs. The results of this review are of importance to the policymakers, government authorities, and utilities engaged in designing and improving FIs for energy efficient buildings. • Reviews financial incentives (FIs) present for green buildings in Canada. • Determines Canadas' FIs vary with respect to number, type, and location. • Identifies factors impacting effectiveness of FIs. • Finds predominant criteria in FIs effectiveness evaluation studies. • Provides approach for evaluation of effectiveness of FIs. [ABSTRACT FROM AUTHOR]

Low Impact Developments (LIDs) employ a series of vegetative techniques to retain rainfall close to the site of origin. Although LIDs offer sustainable runoff management, these infrastructures can be considered a risk to public health due to the presence of pathogens in the runoff and human exposure to contaminated water held in and transported by LIDs. The objective of this study is to examine the disease burden of Gastrointestinal illness (GI) from exposure to LIDs at the residential, neighbourhood, and municipal levels. The authors conducted a meta-analysis of literature on three water features: (1) harvested rainwater obtained from LIDs, (2) surface water, and (3) floodwater. A set of 32 studies were systematically selected to collect values of risks of infection and expressed as the disease burden, i.e. disability adjusted life years (DALYs). The results showed that the percentage of GI illness exceeding the health guidelines were high for harvested rainwater, i.e. 22% of annual disease burden exceeded the WHO guidelines (0.001 DALYs/1000 persons), and 2% exceeded the US EPA guidelines (5.75 DALYs/1000 bathers). Among the six exposures for harvested rainwater, exposure to spray irrigation, exceeded US EPA guidelines whereas; five exposures, i.e. flushing, hosing, daily shower, spray irrigation, and children playing, surpassed the WHO guidelines. Considering LID treatment, the values of annual disease burden from all the selected barriers were below US EPA guidelines however, these values exceeded the WHO guidelines for three barriers i.e. water plaza, grass swale, and open storage ponds. These findings provide a broader perspective of the disease burden associated with LIDs and emphasise to consider the type of exposures and required treatment barriers for developing LID infrastructures in urban areas. Unlabelled Image • A meta-analysis was performed to assess health risks of low impact developments (LIDs). • Proportion of diarrheal illness exceeding WHO guidelines was high for harvested rainwater. • The disease burden of spray irrigation surpassed the WHO and US EPA guidelines. • The DALYs of LIDs in catchment with aged infrastructure exceeded the health guidelines. [ABSTRACT FROM AUTHOR]

Hydrogen is one of the highly promising clean solutions to address the concerns of energy security in the future given the rapid rate of depletion of naturally occurring hydrocarbon sources. However, it is of immense importance that hydrogen is obtained through sources that ensure sustainability. Thermochemical water-splitting processes are among such routes of hydrogen production that are both sustainable and environmentally benign. Thus, this study focuses on assessing the copper-chlorine thermochemical cycles that are among the more promising cycles of the chlorine family in terms of efficiency and cost-effectiveness. Moreover, this study considers a comparative exergoenvironmental evaluation of the four variants of the copper-chlorine cycle that vary in the number and the nature of steps. A comparison in this regard is carried out between the various steps of each cycle in terms of the component-associated environmental impact rates and environmental impact rates of energy transfer as well as the overall environmental impacts of all cycles. In addition, a comparison of the global warming potential of hydrogen synthesized through utilizing various electricity sources is also performed. Based on our evaluations, hydrolysis and electrolysis are the common steps in the five-step cycle, the four-step cycle, and the three-step cycle configuration 1 yielding the highest component-associated environmental impact rates and environmental impact rates of energy transfer, respectively. Conversely, in the three-step cycle configuration 2, the electrolysis and thermal decomposition steps yield the highest corresponding values, respectively. In addition, the three-step cycle configuration 2 (4,869 mPts/h) and the five-step cycle (3,194 mPts/h) have the highest and the lowest component-associated environmental impact rates, respectively while the five-step (530,694 mPts/h) and the four-step (248,050 mPts/h) cycles result in the highest and the lowest environmental impact rates of energy transfer, respectively. • Exergoenvironmental analyses of three variants of Cu–Cl thermochemical cycle. • Comparison of environmental impact rate of energy transfer. • Comparison of component-associated environmental impact rate. • Comparison of global warming potential for various electricity sources. [ABSTRACT FROM AUTHOR]

Abstract Globally the trend of water reuse has been increasing. The public perception and government regulations are supportive for reclaimed water use in Canada. Reclaimed water can be used in variety of applications that may have different performance in economic, environmental and social dimensions for various stakeholders, indicating decision on water reuse selection is complex. This research proposes a multi-criteria multi-decision-makers framework combining multicriteria decision analysis (MCDA) and game theory for a selection of a sustainable water reuse application. The proposed framework is applied to the City of Penticton, BC, Canada. The evaluation criteria included were environmental: fresh water saving, energy use, and carbon emissions; economic: annualized life cycle cost; and social: government policy, public perception, and human health risk for three stakeholders: municipality, citizens, and farm operators. The game theory is applied to eight water reuse options considering a cooperative game. The result shows that lawn, golf course and public park irrigation and toilet flushing with an equal sharing of municipal benefits between the municipality and citizens is the optimal solution. By using the solution, the municipality can have an additional saving of approximately $35/household/year and the citizens have to spend an additional amount of approximately $100/household/year for dual plumbing of toilet and lawn for reclaimed water use. The additional expenditure for the citizens is within Canada's public willingness to pay an additional charge for reclaimed water use. The scenario analysis shows that the weights of sustainability criteria are important in decision-making. Also, the sensitivity analysis shows that the change in the amount of reclaimed water availability can affect water reuse sustainability performance. The proposed framework can also be used in other applications by changing the number of evaluation criteria and stakeholders as required. Graphical abstract Unlabelled Image Highlights • Water reuse decision is complex having conflicting criteria and multi-stakeholders. • Multicriteria decision analysis and game theory are combined and applied. • Game theory efficiently gives solutions in water reuse decision conflict. • Estimated expenses for water reuse are within the willingness to pay by citizens. • The framework can be adapted to other applications involving multi-stakeholders. [ABSTRACT FROM AUTHOR]

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]

This article is the first in a series of two papers. Paper I focuses on model conceptualization and development, and Paper II in the series focuses on model validation and implementation. The amount of water reuse has been increasing across the globe. Wastewater can be treated based on the intended end use of reclaimed water. Fit-for-purpose wastewater treatment (WWT) simultaneously considers intended end use, economic viability, and environmental sustainability. WWT technologies differ mainly in terms of treatment efficiency, cost, energy use, and associated carbon emissions. The planning and evaluation of water reuse projects requires a decision support tool (DST) to evaluate alternative WWT trains and water reuse applications. However, such a DST is not available in the publically accessible literature. A DST, FitWater, has been developed for the evaluation of WWT for various urban reuses. The evaluation is based on the following criteria: amount of reclaimed water production, health risk of water reuse, cost, energy use, and carbon emissions. The cost is estimated as annualized life cycle cost and health risk is estimated using quantitative microbial risk assessment. The uncertainty analysis has been performed using probabilistic and fuzzy-based methods. A multi-criteria decision analysis, using fuzzy weighted average, is employed to aggregate different criteria and generate a final score. FitWater ranks alternative WWT trains based on the resulting final score. The proposed FitWater DST is user-friendly, and its application is demonstrated using an example. The DST can be enhanced to include additional treatment technologies and carbon emissions of different treatment processes. [ABSTRACT FROM AUTHOR]

This paper is the second in a series of two papers. In Paper I, a decision support tool (DST), FitWater, was developed for evaluating the potential of wastewater treatment (WWT) trains for various water reuse applications. In the present paper, the proposed DST has been tested and implemented. FitWater has been tested with several existing WWT plants in Canada and the USA, demonstrating FitWater's effectiveness in estimating life cycle cost (LCC), health risk, and energy use. FitWater has also been implemented in a newly planned neighbourhood in the Okanagan Valley (BC, Canada) by developing 12 alternative WWT trains for water reuse in lawn and public parks irrigation. The results show that FitWater can effectively rank WWT train alternatives based on LCC, health risk, amount of reclaimed water, energy use, and carbon emissions. Moreover, functions have been developed for the variation of unit annualized LCC and energy intensity per unit log removal of microorganisms in different treatment technologies with varying plant capacities. The functions have power relations, showing the economies of scale. FitWater can be applied to identify a cost-effective, risk-acceptable, and energy efficient wastewater treatment train with a plant capacity of 500 m 3 /day or more. Furthermore, FitWater can be used to assess potential economic impacts of developing microbiologically stringent effluent standards. The capability of FitWater can be enhanced by including physio-chemical quality of wastewater, additional treatment technologies, and carbon emissions from wastewater decomposition processes. [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]

Ongoing climate action programs are prompting more stringent energy performance standards for buildings. Consequently, energy retrofitting of existing buildings has become a common climate action initiative around the world. Building owners are keen to assess the technical and financial feasibility of energy retrofitting in pre-project planning stages. Life cycle cost analysis (LCCA) involves assessment of the economic cost of an asset or a service. LCCA, which is a data-intensive process, is heavily affected by data uncertainties; however, traditional deterministic LCCA models are oblivious to data uncertainty and this can have a significant effect on the final decision. As a solution, this paper proposes a novel LCCA approach for building energy retrofits. The proposed approach calculates life cycle cost (LCC) by adopting fuzzy set theory. In order to illustrate the proposed methodology, a case study was conducted for a public building operated in the Okanagan region of British Columbia, Canada. Two energy retrofit alternatives − a major retrofit and a deep retrofit − were compared using the proposed fuzzy set theory-based approach and the traditional deterministic LCCA approach. Even though the deterministic result had a strong membership to the fuzzy membership function of the LCC, the range of possible LCC is wide. Use of the fuzzy-based approach would enable the forecasting of possible future LCC as a result of changes in macro-economic factors. This information would allow building managers to plan for adverse future scenarios. [ABSTRACT FROM AUTHOR]

Although Canada has abundant freshwater resources, many cities still experience seasonal water shortage. Supply-side and demand-side management is a core strategy to address this water shortage. Under this strategy, reclaimed water, which the Canadian public is willing to use for non-potable purposes, is an option. However, no universal guidelines exist for reclaimed water use. Despite the federal government's long-term goal to develop guidelines for many water reuse applications, guidelines have only been prescribed for reclaimed water use in toilet and urinal flushing in Canada. At the provincial level, British Columbia (BC) has promulgated guidelines for wide applications of reclaimed water but only at broad class levels. This research has investigated and proposed probabilistic risk-based recommended values for microbial quality of reclaimed water in various non-potable urban reuses. The health risk was estimated by using quantitative microbial risk assessment. Two-dimensional Monte Carlo simulations were used in the analysis to include variability and uncertainty in input data. The proposed recommended values are based on the indicator organism E . coli . The required treatment levels for reuse were also estimated. In addition, the recommended values were successfully applied to three wastewater treatment effluents in the Okanagan Valley, BC, Canada. The health risks associated with other bacterial pathogens ( Campylobacter jejuni and Salmonella spp.), virus (adenovirus, norovirus, and rotavirus), and protozoa ( Cryptosporidium parvum and Giardia spp.), were also estimated. The estimated risks indicate the effectiveness of the E . coli -based water quality recommended values. Sensitivity analysis shows the pathogenic E . coli ratio and morbidity are the most sensitive input parameters for all water reuses. The proposed recommended values could be further improved by using national or regional data on water exposures, disease burden per case, and the susceptibility fraction of population. [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]

Urban densification has dominated the land uses and land covers which may jeopardize the quality of life and sustainable development. Moreover, urban densification process exerts stress on buried water infrastructure (BWI) performance. In this study, the need of predicting the change in urban densification and its subsequent impacts on BWI performance over time has drawn attention to conduct a temporal analysis. A hybrid approach was used to select the significant control performance indicators (CPIs) and conduct a temporal analysis. Eight scenarios were generated using the Canadian Council of the Ministers of the Environment Water Quality Index approach to address the change in drinking water quality. The proposed approach was implemented in a municipality of British Columbia, Canada, as a case study. The results showed a 40 % decrease in the BWI performance due to the urban areas have rapidly grown both in population and built-up areas over three decades. Furthermore, an ideal situation was assumed to show that the targeted service level (i.e., 0.5) can be achieved with 3 % to 5 % improvement in every five years of service level. These findings will assist the decision makers to understand the linkage between CPIs to maintain and achieve the required BWI performance. • Urban growth patterns and their impacts on buried water infrastructure (BWI) • Significant control performance indicators were selected using empirical models. • A hybrid approach coupled with water quality index is used for temporal analysis. • The proposed approach was applied to a municipality of British Columbia, Canada. • Over time, 40 % decrease was observed in BWI performance due to densification. [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]

The building stock in the world consumes approximately 40% of the energy and emits one third of the total greenhouse gases emissions (GHG). Improving the energy efficiency in buildings is vital to address the climate change and achieve energy independence (i.e. to become net-zero energy). Improving energy performance in existing buildings has been receiving significant attention recently, which entails reducing energy demand for building operations, without affecting the health and comfort of its occupants. This approach requires strategies beyond mere technical advancements. However, there is limited published literature which has comprehensively addressed these issues. The aim of this paper is to critically review existing body-of-the-knowledge on improving energy efficiency of operating both commercial and institutional buildings. Peer-reviewed journal articles published from year 2000 to 2014 in reputed journals were reviewed. This review investigated contemporary energy efficiency approaches including technical, organizational, and behavioural changes. Based on the comprehensive literature review, a strategy map was developed as a pathway for achieving better building energy performance. It was noted that even though the existing studies predominately focused on technical advancements, approaches such as building behavioural changes have been largely overlooked. Findings of this study provide an important basis for setting up a national and organization wide strategy for improving the energy efficiency of commercial and institutional buildings. [ABSTRACT FROM AUTHOR]

To develop an effective preventive or proactive repair and replacement action plan, water utilities often rely on water main failure prediction models. However, in predicting the failure of water mains, uncertainty is inherent regardless of the quality and quantity of data used in the model. To improve the understanding of water main failure, a Bayesian framework is developed for predicting the failure of water mains considering uncertainties. In this study, Bayesian model averaging method (BMA) is presented to identify the influential pipe-dependent and time-dependent covariates considering model uncertainties whereas Bayesian Weibull Proportional Hazard Model (BWPHM) is applied to develop the survival curves and to predict the failure rates of water mains. To accredit the proposed framework, it is implemented to predict the failure of cast iron (CI) and ductile iron (DI) pipes of the water distribution network of the City of Calgary, Alberta, Canada. Results indicate that the predicted 95% uncertainty bounds of the proposed BWPHMs capture effectively the observed breaks for both CI and DI water mains. Moreover, the performance of the proposed BWPHMs are better compare to the Cox-Proportional Hazard Model (Cox-PHM) for considering Weibull distribution for the baseline hazard function and model uncertainties. [ABSTRACT FROM AUTHOR]

Due to incomplete and partial information, data/information from multiple sources with different credibility or confidence, and the involvement of human (expert) judgment for the interpretation and integration of data/information, uncertainties become a major concern for the development of water main failure prediction model. To reduce these uncertainties, a new Bayesian belief network based data fusion model is developed for the failure prediction of water mains. To accredit the proposed framework, it is implemented to predict the failure of CI and DI pipes of the water distribution network of the City of Calgary. Analysis results indicate that ∼6.16% and 8.20% of the total 18,762 CI and DI pipes are at high and very high failure rates, respectively. The proposed model can be integrated with the geographic information system of the utilities and capable of identifying the most ‘vulnerable’ and ‘sensitive’ pipes within the distribution network as well as estimate the total number of pipes that need maintenance/rehabilitation/replacement (M/R/R) actions. [ABSTRACT FROM AUTHOR]

Energy retrofitting for buildings has gained great attention in recent years due to the significant benefits of reducing environmental impacts and costs. Generally, retrofit planning involves considering criteria such as energy savings, emissions savings, and cost savings. However, the rapid transition of climate and extreme climate forces integrate climate adaptation into retrofit practices. This study examines strategies and modifications necessary to transform the current climate mitigation-based retrofit processes into frameworks that simultaneously improve climate mitigation and adaptation. A comprehensive literature review is conducted on building energy retrofit studies based on climate adaptation. It was found that future climate events are anticipated to be more related to overheating than under-cooling in many regions. Passive retrofit strategies can reduce overheating risks substantially, while the dependency on active cooling is unavoidable in warm climatic regions in future climates. Retrofit strategies designed based on traditional approaches may not be effective and may even worsen the risks of overheating in the future climate due to drastic climate change. Climate resiliency criteria must be adapted to the building retrofit field. Climate modelling and energy simulation have a substantial role in designing retrofits, and yet significant research and development is required to penetrate the current retrofit practices. The synthesis of the findings guides the systematic and careful designing and implementation of building energy retrofits. These findings offer valuable insights to policymakers, urban planners, and researchers seeking to improve buildings' energy performance and resiliency and act as a guideline to implement climate change adaptation strategies. • Reviewed climate adaptation-based retrofit designing and planning studies. • Revealed a significant gap in existing retrofit frameworks that consider both climate mitigation and adaptation. • Highlighted careful design and implementation of retrofits is necessary to overcome future climate risks. • Presented a comprehensive guideline to integrate climate adaptation aspects into current retrofit practices. • Suggested future research directions, including the development of climate resilience benchmarks. [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]

Dissolved organic carbon (DOC) is a recognized indicator of natural organic matter (NOM) in surface waters. The aim of this paper is twofold: to evaluate the impact of geophysical characteristics, climate and ecological zones on DOC concentrations in surface waters and, to develop a statistical model to estimate the regional variability of these concentrations. In this study, multilevel statistical analysis was used to achieve three specific objectives: (1) evaluate the influence of climate and geophysical characteristics on DOC concentrations in surface waters; (2) compare the influence of geophysical characteristics and ecological zones on DOC concentrations in surface waters; and (3) develop a model to estimate the most accurate DOC concentrations in surface waters. The case study involved 115 catchments from surface waters in the Province of Quebec, Canada. Results showed that mean temperatures recorded 60 days prior to sampling, total precipitation 10 days prior to sampling and percentages of wetlands, coniferous forests and mixed forests have a significant positive influence on DOC concentrations in surface waters. The catchment mean slope had a significant negative influence on DOC concentrations in surface waters. Water type (lake or river) and deciduous forest variables were not significant. The ecological zones had a significant influence on DOC concentrations. However, geophysical characteristics (wetlands, forests and slope) estimated DOC concentrations more accurately. A model describing the variability of DOC concentrations was developed and can be used, in future research, for estimating DBPs in drinking water as well evaluating the impact of climate change on the quality of surface waters and drinking water. [ABSTRACT FROM AUTHOR]

Abstract: The development of cost-effective, durable and sensitive on-line water quality monitoring sensors that can be installed across water distribution networks has attracted attention to increase the frequency of monitoring and hence reduce the risk of accidental or deliberate contaminations or improve routine control of water quality. This paper presents microsensors fabricated and implemented in a serpentine channel interface for the measurement of pH and conductivity, two important water quality parameters. The performance of these sensors was tested in both still (static) and flowing (dynamic) water. The serpentine channel interface, numerically optimized, provides a constant flow and a constant outlet pressure condition for dynamic experiments. Tests conducted for evaluating the effect of the exposure time on the sensor performance show no change in the sensor response even after one month. Finally, the pH and conductivity sensors were compared against the common commercial sensors used for evaluating water quality. The results show that the pH and conductivity sensors are as precise as the commercial sensors in both static and dynamic conditions. However, the cost of the sensors presented here is significantly lower than that of the commercial sensors. [Copyright &y& Elsevier]

This study employs fuzzy regression and fuzzy multivariate clustering techniques to analyze arsenic-polluted water samples originating from acid rock drainage in waste rock dumps. The research focuses on understanding the complex relationships between variables associated with arsenic contamination, such as water arsenic concentration, pH levels, and soil characteristics. To this end, fuzzy regression models were developed to estimate the relationships between water arsenic concentration and independent variables, thus, incorporating the inherent uncertainties into the analysis. Furthermore, multivariate fuzzy k-means clustering analysis facilitated the identification of fuzzy-based clusters within the dataset, providing insights into spatial patterns and potential sources of arsenic pollution. The pairwise comparisons indicated the strongest correlation of 0.62 between soil total arsenic and pH, while the weakest correlation of 0.13 was observed between soil-soluble arsenic and soil iron, providing valuable insights into their relationships and impact on water arsenic levels. The associated uncertainties in the relationships among the variables were determined based on the degree of belongingness of each data point to various fuzzy sets. Three distinct clusters emerged from the analysis: Cluster 1 comprised Points 5, 6, and 7; Cluster 2 included Points 1, 2, 3, 4, 8, and 9; and Cluster 3 consisted of Points 10, 11, 12, and 13. The findings enhance our understanding of the factors influencing arsenic contamination to provide an effective mitigation strategy in acid rock drainage scenarios. This research also demonstrates the applicability and effectiveness of fuzzy regression and fuzzy multivariate clustering in the analysis of arsenic-polluted water samples. [Display omitted] • Arsenic-contaminated water through acid drainage from a gold mine was analyzed. • Fuzzy regression and clustering analysis, suited for small samples, were applied. • Fuzzy concepts addressed the vagueness of relationship between chemical components. • Understanding the relationships helps in adopting an efficient mitigation strategy. [ABSTRACT FROM AUTHOR]

Marine oil spill response is a time sensitive and complex task, in which the management of oily wastewater generated from response operations could be a bottleneck limiting the response capacity and efficiency. This study developed a multi-agent decision support system to effectively coordinate mechanical containment and recovery (MCR) of spilt oil and oily wastewater management (OWM) operations. The system aims to minimize the overall response time, cost, and the volume of weathered oil by applying evolutionary optimization, oil weathering process, and response operational agents. The multi-agent system was used to manage an incident through a hypothetical case study in Canada. The system enables the scheduling of available response assets considering all complex operational details of MCR and OWM, such as available oily wastewater storage and transportation capacities and the competitive skimming process of various response vessels. Implementing the evolutionary multi-objective optimization led to a considerable reduction in response time (about 13.6% or 67 hr), cost (about 1.4% or CA$24,800), and volume of weathered oil (about 9.2% or 19 m3) compared to the shortest distance approach. The developed multi-agent system can facilitate decision-making in complex marine oil spill response tasks for maximizing response efficiency. [Display omitted] • A decision support system is developed for effective marine oil spill management. • Oil spill response and oily waste management operations were optimized together. • Overall response time and cost, as well as volume of weathered oil were minimized. • The multi-agent system was tested on a comprehensive case study in Western Canada. • Multi-objective optimization approaches outperformed shortest distance model. [ABSTRACT FROM AUTHOR]

Hydrogen is a fuel with immense potential of satisfying the need for environmentally benign energy sources, and waste-derived hydrogen is promising in diverting waste streams away from landfills and other costly treatment. Nonetheless, many waste-to-hydrogen pathways are incipient and require significant efforts to be established as an indispensable element of the path towards sustainability. This review comprehensively evaluates waste-to-hydrogen technologies from technological, economic, environmental, and societal viewpoints. State-of-the-art of five technologies was summarized, focusing on emerging trends in published literature. Several knowledge gaps, future research prospects, and possible improvements related to performance, greenhouse gas emissions, production costs, hydrogen-based transportation, and public acceptance were also identified. Fulfilling the lack of techno-economic and environmental studies of waste-to-hydrogen routes, incorporation of renewable energy into processes, and necessities of scaling-up and production cost reduction are prominent among research needs recognized through this review. Conclusions of this study will be beneficial towards sustainably integrating hydrogen into large-scale energy systems. • Hydrogen production from different types of wastes was critically reviewed. • The state-of-the-art of five waste-to-hydrogen processes was compiled. • Emissions of waste-based hydrogen production are lower than conventional methods. • Thermochemical methods perform better than biochemical methods techno-economically. • Lowered cost and improved safety increase social acceptance of waste-to-hydrogen. [ABSTRACT FROM AUTHOR]