Life cycle assessment of MSF,MED and RO desalination technologies

In this work, a comparison of the commonly deployed commercial desalination technologies worldwide—multistage flash (MSF), multieffect evaporation and reverse osmosis (RO)—is assessed by applying life cycle analysis (LCA). LCA, a powerful, and internationally accepted tool used to examine environmental cradle-to-grave consequences of making and using products and services, identifies and quantifies energy and material usage and waste discharges. The International Standard Organization (ISO) 14000 impact factors, which are internationally accepted standard indicators for environmental impact assessment, have been evaluated, and different evaluation methods (Centre for Environmental Studies (CML) 2 baseline 2000, Eco-Points 97 and Eco-Indicator 99) have been applied to different scenarios. The assessment includes the entire life cycle of each desalination process, encompassing extraction and processing raw materials, manufacturing, transportation and distribution, plant operation and final reject disposal.     

Indicators of bioenergy-related certification schemes – An analysis of the quality and comprehensiveness for assessing local/regional environmental impacts

Bioenergy is receiving increasing attention because it may reduce greenhouse gas emissions, secure and diversify energy supplies and stimulate rural development. The environmental sustainability of bioenergy production systems is often determined through life-cycle assessments that focus on global environmental effects, such as the emission of greenhouse gases or air pollutants. Local/regional environmental impacts, e.g., the impacts on soil or on biodiversity, require site-specific and flexible options for the assessment of environmental sustainability, such as the criteria and indicators used in bioenergy certification schemes.In this study, we compared certification schemes and assessed the indicator quality through the environmental impact categories, using a standardized rating scale to evaluate the indicators. Current certification schemes have limitations in their representation of the environmental systems affected by feedstock production. For example, these schemes predominantly use feasible causal indicators, instead of more reliable but less feasible effect indicators. Furthermore, the comprehensiveness of the depicted environmental systems and the causal links between human land use activities and biophysical processes in these systems have been assessed. Bioenergy certification schemes seem to demonstrate compliance with underlying legislation, such as the EU Renewable Energy Directive, rather than ensure environmental sustainability. Beyond, certification schemes often lack a methodology or thresholds for sustainable biomass use. Lacking thresholds, imprecise causal links and incomplete indicator sets may hamper comparisons of the environmental performances of different feedstocks. To enhance existing certification schemes, we propose combining the strengths of several certification schemes with research-based indicators, to increase the reliability of environmental assessments.     

Capital budgeting process for electric power utilities—an analytic hierarchy process approach

Currently, the electric power industry in U.S.A. is undergoing substantial regulatory and organizational changes with respect to market economics as well as pollution. Under these changing circumstances, in this paper, we utilize the concepts of analytic hierarchy process (AHP) and integer programming (IP) to model the capital budgeting process under both finance and pollution considerations. In particular, first we show how a decision maker can simultaneously incorporate the hard-to-quantify factors (pollutants) as well as easy-to-quantify factors (finance factors) into a hierarchy. Next, we show how priority weights derived from the hierarchy can be used to determine the optimal set of projects to be constructed. Also, we show how the entire capital budgeting process can be performed via an illustrative numerical example. It is hoped that the comprehensive, systematic, and consistent approach shown in this paper will provide the electric power utilities an additional decision support tool in their capital budgeting process. © 1998 John Wiley & Sons, Ltd.     

A comparative study among fossil fuel power plants in PJM and California ISO by DEA environmental assessment

This study compares among fossil fuel power plants in PJM and California ISO by their unified (operational and environmental) performance. DEA (Data Envelopment Analysis) is used as a methodology. For comparative analysis, DEA incorporates strategic concepts such as natural and managerial disposability into the computational process. This study explores both how to measure Returns to Scale (RTS) under natural disposability and how to measure Damages to Scale (DTS) under managerial disposability. This empirical study obtains two implications on US energy policy. One of the two policy implications is that California ISO outperforms PJM in terms of the three unified efficiency measures. The result implies that strict regulation on undesirable outputs, as found in California, is important in enhancing the performance of US fossil fuel power plants. Thus, it is necessary for federal and local governments to regulate the fossil fuel power plants under the strict implementation of environmental protection. Under such a policy direction, it is possible for US fossil fuel power plants to attain economic prosperity (by enhancing their operational efficiencies) and to satisfy environmental regulation (by enhancing their environmental efficiencies). The other policy implication is that coal-fired and gas-fired power plants in PJM and California ISO need to reduce their operational sizes or introduce technology innovation on desirable and undesirable outputs and/or new management for environmental protection within their operations. Meanwhile, oil-fired power plants may increase their operational sizes if they can introduce technology innovation and new management on undesirable outputs.     

The influence of perceived uncertainty on entrepreneurial action in emerging renewable energy technology; biomass gasification projects in the Netherlands

Emerging renewable energy technologies cannot break through without the involvement of entrepreneurs who dare to take action amidst uncertainty. The uncertainties that the entrepreneurs involved perceive will greatly affect their innovation decisions and can prevent them from engaging in innovation projects aimed at developing and implementing emerging renewable energy technologies. This article analyzes how perceived uncertainties and motivation influence an entrepreneur's decision to act, using empirical data on biomass gasification projects in the Netherlands. Our empirical results show that technological, political and resource uncertainty are the most dominant sources of perceived uncertainty influencing entrepreneurial decision-making. By performing a dynamic analysis, we furthermore demonstrate that perceived uncertainties and motivation are not stable, but evolve over time. We identify critical factors in the project's internal and external environment which influence these changes in perceived uncertainties and motivation, and describe how various interactions between the different variables in the conceptual model (internal and external factors, perceived uncertainty, motivation and previous actions of the entrepreneurs) positively or negatively influence the decision of entrepreneurs to continue entrepreneurial action. We discuss how policymakers can use these insights for stimulating the development and diffusion of emerging renewable energy technologies.     

Improving the environmental performance of biofuels with industrial symbiosis

In the production of biofuels for transport many critics have argued about the poor energy efficiency and environmental performance of the production industries. Optimism is thus set on the production of second generation biofuels, while first generation biofuels continue to dominate worldwide. Therefore it is interesting to consider how the environmental performance of first generation biofuel industries can be improved. The field of industrial symbiosis offers many possibilities for potential improvements in the biofuel industry and theories from this research field are used in this paper to highlight how environmental performance improvements can be accomplished. This comes in the form of by-product synergies and utility synergies which can improve material and energy handling. Furthermore, the processes and products can gain increased environmental performance improvements by the adaption of a renewable energy system which will act as a utility provider for many industries in a symbiotic network. By-products may thereafter be upcycled through biogas production processes to generate both energy and a bio-fertilizer. A case study of an actual biofuel industrial symbiosis is also reviewed to provide support for these theories.     

Conflicting strategies towards sustainable heating at an urban junction of heat infrastructure and building standards

Approaches to ‘sustainability transitions’ stress the possibility of aligning actors around a shared vision of the future, e.g. at the scale of a city. Empirical accounts reveal how difficult such coordination often is due to contradictory views involved. How can we better understand related processes of searching and negotiation? What does this mean for the organization of decision making processes regarding long-term infrastructural change?We analyze a conflict which erupted in Freiburg, Germany when two strategies of reducing environmental impacts of space heating were to be applied in the Vauban ‘model district’: A) Efficient co-generation of heat and power (CHP) combined with district heating systems (DHS), and B) Reducing heat demand by low-energy designs and ambitious energy standards (‘passive house standard’). In order to understand the politics of infrastructure development, we unravel 1) enabling factors and driving forces of the conflict, 2) normative content of opposing viewpoints, 3) resources tapped into for settling the disagreement, and 4) the institutional setup of such decision making about energy policy priorities in the municipality.We reflect on implications of such a perspective on how policies and how governance arrangements should ideally be shaped and take a brief outlook on further research needed.     

A comparative analysis of biogas and hydrogen,and the impact of the certificates and blockchain new paradigms

Solar and wind energy technologies, due to their nature of weather dependency, have been recognized as not the complete solution for the renewable energy transition. Creating a solution for the short fall is empirical if we are to remove the dependency on fossil fuels and reach net zero targets. The production of hydrogen, biogas and other gases can be produced sustainably, which can also allow for the utilization of waste materials or the ability to store energy and allow a greater positive impact on our environment. However, production of these gases is not always as transparent or environmentally friendly as perceived, so with the aid of certification and blockchain, we can create a system that can guarantee their environmentally positive origin, and ultimately help assist the transition to a greener future. This paper explores the varying production methods, with consideration to their environmental impact, and the implications of the use of certificates and blockchain to monitor production, trade and usage.     

From the global efforts on certification of bioenergy towards an integrated approach based on sustainable land use planning

This paper presents an overview of 67 ongoing certification initiatives to safeguard the sustainability of bioenergy. Most recent initiatives are focused on the sustainability of liquid biofuels. Content-wise, most of these initiatives have mainly included environmental principles. Despite serious concerns in various parts of the world on the socio-economic impacts of bioenergy production, these are generally not included in existing bioenergy initiatives. At the same time, the overview shows a strong proliferation of standards. The overview shows that certification has the potential to influence direct, local impacts related to environmental and social effects of direct bioenergy production. Key recommendations to come to an efficient certification system include the need for further harmonization, availability of reliable data and linking indicators on a micro, meso and macro levels. Considering the multiple spatial scales, certification should be combined with additional measurements and tools on a regional, national and international level. The role of bioenergy production on indirect land use change (ILUC) is still very uncertain and current initiatives have rarely captured impacts from ILUC in their standards. Addressing unwanted LUC requires first of all sustainable land use production and good governance, regardless of the end-use of the product. It is therefore recommended to extend measures to mitigate impacts from LUC to other lands and feedstock.     

Assigning priorities to actions in a pipeline transporting hydrogen based on a multicriteria decision model

Nowadays there is a pressing need to implement changes in the global energy structure, such that it incorporates new features and changes the way that we use fossil fuels. In this scenario, hydrogen is projected as the fuel of the future. Among the possible modes that can be used for its transportation, the pipeline is singled out as it is the safest and the most economically viable means of transporting large quantities of the gas. However, accidents to pipelines have been recorded and they often result in catastrophic consequences for society. In this context, this paper proposes novelties in multidimensional risk assessment for the transportation of hydrogen by pipeline. Thus, a multicriteria decision model is proposed, using multiattribute utility theory, which incorporates the behavior of a decision maker and considers three dimensions of risk assessment: the human, financial and environmental dimensions. By taking these into consideration, the decision maker may well get precious and differentiated information about the risk management of pipelines.     

Application of sensitivity analysis in design of sustainable buildings

Building performance can be expressed by different indicators such as primary energy use, environmental load and/or the indoor environmental quality and a building performance simulation can provide the decision maker with a quantitative measure of the extent to which an integrated design solution satisfies the design objectives and criteria. In the design of sustainable buildings, it is beneficial to identify the most important design parameters in order to more efficiently develop alternative design solutions or reach optimized design solutions. Sensitivity analyses make it possible to identify the most important parameters in relation to building performance and to focus design and optimization of sustainable buildings on these fewer, but most important parameters. The sensitivity analyses will typically be performed at a reasonably early stage of the building design process, where it is still possible to influence the most important design parameters. A methodology of sensitivity analysis is presented and an application example is given for design of an office building in Denmark.     

Metrological management evaluation based on ISO10012: an empirical study in ISO-14001-certified Spanish companies

Environmental management systems based on the ISO 14001 standard rely strongly on metrological measurement and confirmation processes to certify the extent to which organizations monitor and improve their environmental behavior. Nevertheless, the literature lacks in studies that assess the influence of these metrological processes on the performance of environmental management in organizations, even now that the international standard ISO 10012 is already available to establish requisites and guidelines for the development of a metrological management system that is compatible with any other standardized management system. This work seeks to assess that influence through the development of an evaluation model for metrological management, which is then validated through an experimental analysis of the results obtained from the application of an audit process in 11 Spanish companies, all ISO-14001-certified and operating in different industrial sectors.     

Life-cycle assessment in the renewable energy sector

The Polish energy industry is facing challenges regarding energetic safety, competitiveness, improvement of domestic companies and environmental protection. Ecological guidelines concern the elimination of detrimental solutions, and effective energy management, which will form the basis for sustainable development. The Polish power industry is required to systematically increase the share of energy taken from renewable sources in the total energy sold to customers. Besides the economic issues, particular importance is assigned to environmental factors associated with the choice of energy source. That is where life-cycle assessment (LCA) is important. The main purpose of LCA is to identify the environmental impacts of goods and services during the whole life cycle of the product or service. Therefore LCA can be applied to assess the impact on the environment of electricity generation and will allow producers to make better decisions pertaining to environmental protection. The renewable energy sources analysed in this paper include the energy from photovoltaics, wind turbines and hydroelectric power. The goal and scope of the analysis comprise the assessment of environmental impacts of production of 1 GJ of energy from the sources mentioned above. The study will cover the construction, operation and waste disposal at each power plant. Analysis will cover the impact categories, where the environmental influence is the most significant, i.e. resource depletion, global warmth potential, acidification and eutrophication. The LCA results will be shown on the basis of European and Australian research. This analysis will be extended with a comparison between environmental impacts of energy from renewable and conventional sources. This report will conclude with an analysis of possibilities of application of the existing research results and LCA rules in the Polish energy industry with a focus on Poland's future accession to the European Union. Definitions of LCA fundamental concepts, its methodology and application are described in the ISO 14040-14049 series of standards. These standards have already been introduced in some countries, but in Poland they are still at the stage of translation into Polish. Nevertheless some companies in Poland try to assess how their products influence the environment and what are the possibilities of technology improvement in the existing production process reduce their environmental impact.     

An investigation of the effect of environmental factors on the budgets of heat,water vapor,and carbon dioxide within a tree

In this study, we have attempted to model the budgets of heat, water vapor, and carbon dioxide within three-dimensional vegetation. This model consists of three submodels: a model for turbulent flow within vegetation, a model for radiation transfer within vegetation, and a stomatal conductance model. We adopted our own turbulence model for the flow within vegetation and used Ross’s model for radiation transfer within vegetation and a stomatal conductance model by Collatz et al. These three submodels were integrated into the present model, which we applied to a single model tree to investigate how environmental factors affected the budgets of heat, water vapor, and carbon dioxide within a tree.     

Adoption of green electricity policies: Investigating the role of environmental attitudes via big data-driven search-queries

Despite the rising influence of public opinion on government energy policy formulation and implementation, the roles of pro and/or anti-environmental attitudes among residents have not been empirically examined. To quantify time-varying environmental attitudes among local residents, we exploit geo-specific Google search-query data derived from Internet-based “big data” and verify through ordinary least squares regression outcomes regarding environmental behavior. For the purpose of drawing policy implications, we revisit decisions by state governments of the United States to adopt three well-known green electricity policies: renewable energy portfolio, net metering rules, and public benefit funds. As some states have not yet adopted some (or any) of these policies, unlike previous studies, we handle the issue by examining right-censored data and applying a duration-based econometric method called the accelerated failure time model. We found state residents’ environmental attitudes to have statistically significant roles, after controlling for other traditional time-varying policy adoption factors. Interestingly, the extent to which anti-environmental attitudes affect a state’s policy adoption differs across green energy policies, and knowing this can help a local government formulate better-tailored environmental policy. In particular, researchers can use our method of incorporating citizens’ environmental attitudes to discuss relevant issues in the field of energy policy.     

The trade-off between bioenergy and emissions with land constraints

Agricultural biofuels require the use of scarce land, and this land has opportunity cost. We explore the objective function of a social planner who includes a land constraint in the optimization decision to minimize environmental cost. The inclusion of this land constraint in our optimization model motivates the measurement of emissions on a per-hectare basis. Switchgrass and corn are modeled as competing alternatives to show how the inclusion of a land constraint can influence life cycle rankings and alter policy conclusions. With land use unconstrained, ethanol produced from switchgrass is always an optimal feedstock relative to ethanol produced from corn. With land use constrained, however, our results show that it is unlikely that switchgrass would be optimal in the midwestern United States, but may be optimal in southern states if carbon is priced relatively high. Whether biofuel policy advocates for one feedstock over another should consider these contrasting results.     

Energy paradox and political intervention: A stochastic model for the case of electrical equipments

This paper develops a model that explains the delay of decisions to adopt profitable energy-saving investments. This problem is known as the energy paradox. The model rationalizes the profitability requirements raised by the irreversibility, the uncertainty and the decrease of costs as a result of learning by doing. In this context, the wait gives investors more visibility and more lower investment costs, which gives them an option value. The representative agent has an interest to postpone its energy saving decision until future benefits increase and equalize its required option value. Formally, we internalize these explanatory factors in a stochastic model where the updated energy saving benefits follows a geometric Brownian motion. To affirm the capacity of the model, we generate simulation results for two equipments for electrical uses. Beyond that, we extend the model to simulate the effects of energy policy instruments to promote adoption of such equipments. Simulations prove that the taxation of energy prices is likely to be more effective than the subsidy for energy-saving equipments. It is also found that the combination of these instruments amplifies the adoption of energy-saving equipments and generates very favorable economic and environmental externalities.     

化工园区用排水网络优化专家系统设计

叙述了某化工园区用排水网络优化专家系统通过人机交互,利用数据管理模块和管网监控模块,实现了园区基线用水数据的管理分析、管网在线监控和应急处理等功能,利用水网络优化模块实现单杂质用水网络新鲜水用水量最小化的优化计算并自动生成新的管网拓扑图,利用决策支持模块对优化方案进行碳排放、节水、能耗、投入产出比等定量定性分析,直接为决策者提供参考,指出,该系统能够有效提高园区管理部门和企业的用水管理水平,提高新鲜水使用效率。     

动力运行工艺过程环境因素识别与评价

建立和实施环境管理体系,环境因素具有非常重要的地位,环境因素的识别和评价是建立和运行环境管理体系的基础.正确识别与评价各类环境因素,并实现对重要环境因素的有效控制是建立和实施环保体系的主要工作,因而对重要环境因素评价的方法进行深入研究非常必要.通过对环境因素及相关的内容作深入研究,从而为某集团能够顺利地通过ISO14001环境管理体系认证起到很好的参考作用.     

Measuring improvement in energy efficiency of the US cement industry with the ENERGY STAR Energy Performance Indicator

The lack of a system for benchmarking industrial plant energy efficiency represents a major obstacle to improving efficiency. While estimates are sometimes available for specific technologies, the efficiency of one plant versus another could only be captured by benchmarking the energy efficiency of the whole plant and not by looking at its components. This paper presents an approach used by ENERGY STAR to implement manufacturing plant energy benchmarking for the cement industry. Using plant-level data and statistical analysis, we control for factors that influence energy use that are not efficiency, per se. What remains is an estimate of the distribution of energy use that is not accounted for by these factors, i.e., intra-plant energy efficiency. By comparing two separate analyses conducted at different points in time, we can see how this distribution has changed. While aggregate data can be used to estimate an average rate of improvement in terms of total industry energy use and production, such an estimate would be misleading as it may give the impression that all plants have made the same improvements. The picture that emerges from our plant-level statistical analysis is more subtle; the most energy-intensive plants have closed or been completely replaced and poor performing plants have made efficiency gains, reducing the gap between themselves and the top performers, whom have changed only slightly. Our estimate is a 13 % change in total source energy, equivalent to an annual reduction of 5.4 billion/kg of energy-related carbon dioxide emissions.