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1.
Pervasive Computing will bring about both additional loads on and benefits to the environment. The prevailing assessment of positive and negative effects will depend on how effectively energy and waste policy governs the development of ICT infrastructures and applications in the coming years. Although Pervasive Computing is not expected to change the impact of the technosphere on the environment radically, it may cause additional material and energy consumption due to the production and use of ICT as well as severe pollution risks that may come about as a result of the disposal of electronic waste. These first-order environmental impacts are to be set off against the second-order effects, such as higher eco-efficiency due to the possibility to optimize material and energy intensive processes or to replace them by pure signal processing (dematerialization). The potential environmental benefits from such second-order effects are considerable and can outweigh the first-order effects. But changes in demand for more efficient services (third-order effects) can counterbalance these savings. The experience gained thus far with ICT impacts has shown that such a rebound effect occurs in most cases of technological innovations.  相似文献   

2.
  总被引:3,自引:0,他引:3  
We review the major empirical analyses of the related concepts of dematerialization and intensity of use. Dematerialization refen to the absolute or relative reduction in the quantity of materials used and/or the quantity of waste generated in the production of a unit of economic output A common indicator is the intensity of material use, which is the quantity of material used per unit of economic output. Our discussion focuses on seven topics: the environmental Kuznets curve for materials, material use and long wave theory material decomposition analysis, statistical, inpuboutput and dynamic models of material use, and analyses of national material use. We examine the measurement of aggregate material use and waste emissions, hypothesis testing, the importance of imports, and forces that countervail dematerialization such as rising affluence and the \"rebound effect.\" We conclude that: our knowledge of the extent of and mechanisms behind the patterns of material use are limited largely to individual materials or very specific industries, and most of those examples are metals; the economy is getting \"lighter\" but the aggregate economic significance of that trend, if any, is unknown; there is no compelling macroeconomic evidence that the US. economy is \"decoupled\" from material inputs; and we know even less about the net environmental effects of many changes in materials use. We caution against gross generalizations about material use, particularly the \"gut\" feeling that technical change, substitution, and a shift t o the \"information age\" inexorably lead to decreased materials intensity and reduced environmental impact. We end with some suggestions for research that may help answer these important questions.  相似文献   

3.
4.
International agreement has been reached to reduce greenhouse gas emissions worldwide. One important way of decoupling CO2 emissions from economic growth is by introducing technical measures to improve energy efficiency. In this article, we assess the influence of developments in energy efficiency and economic structure on the total primary energy consumption in the Netherlands over the period 1980– 1995. We find a distinct decoupling of the economic growth and energy consumption of 1.5% per year in the 15-year analysis period. We measure (technical) changes in energy efficiency by changes in the energy consumption per physical unit of production or activity. The aggregate rate of (technical) energy-efficiency improvement was 1.4% per year over the period 1980–1995. The use of physical production indicators makes it possible to measure energy-efficiency developments without detailed surveys at a very low level of aggregation. When we look at economic structural changes over this period, we find that (i) no substantial shift took place at the level of the economic sectors that we distinguish; (ii) the most energy intensive subsectors grew much faster than the total economy; and (iii) at the subsector level, on average, a sizable decoupling of physical production and value added occurred. We conclude that structural changes, that is, changes in the composition of the economy, did not lead to a net decrease in the energy intensity of the Netherlands over the period 1980–1995.  相似文献   

5.
Towards an Integrated Regional Materials Flow Accounting Model   总被引:1,自引:0,他引:1  
A key challenge in attaining regional sustainability is to reduce both the direct and the indirect environmental impacts associated with economic and household activity in the region. Knowing what these flows are and how they change over time is a prerequisite for this task.
This article describes the early development of an integrated regional materials flow accounting framework. The framework is based on a hybrid (material and economic) multiregional input-output model. Using readily available economic and materials data sets together with transport and logistics data, the framework attempts to provide estimates of household resource flows for any U.K. region at quite detailed levels of product and material disaggregation. It is also capable of disaggregating these flows according to specific socioeconomic criteria such as income level or occupation of the head of household. Allied to appropriate energy and life-cycle assessment data sets, the model could, in addition, be used to map both direct and indirect environmental impacts associated with these flows.
The benefits of such an approach are likely to be a considerable reduction of uncertainties in (1) our knowledge of the household metabolism, and hence our predictions of regional household waste generation; (2) our assessment of the impacts of contemplated changes in industrial process siting, and thereby on other aspects of local and regional planning; and (3) our understanding of the impacts of changes in the pattern of demand for different materials and products. It is concluded that the use of such an integrated assessment tool has much to contribute to the debate on regional sustainability.  相似文献   

6.
Zinc oxide (ZnO) polycrystalline ceramics are the focal point of lightning arrester technology. These semiconductor materials are able to switch rapidly from high to low impedance while handling large amounts of electrical energy. Since the early 1970s, considerable efforts have been made to improve the specific energy absorption capacity and device reliability of such components. This document describes a case study carried out on the life cycle impacts of three different designs of electroceramics made of ZnO. Results show that the best design involves decreasing the diameter while maintaining the thickness of the compound. Of the production, transport, use, and end‐of‐life phases, the use phase is found to contribute by far the most to environmental impacts, with leakage currents in the 10?6 ampere range. The next‐largest impacts come in the transport and production stages. Sensitivity analysis shows that impacts associated with the production stage originate from ZnO production and are related to the by‐products (heavy metals) of zinc metallurgy.  相似文献   

7.
    
Although previous studies point to much (untapped) potential for energy efficiency enhancement in industry, empirical research that adapts findings of environmental control to the context of energy management remains widely neglected. Specifically, previous environmental research suggests that the implementation of energy management control systems (EnMCS) could be an effective lever for companies to enhance their production systems and operations toward energy efficiency. Yet, empirical evidence for this theoretical proposition is rather missing; thus, debate continues regarding whether the high investments to set up a comprehensive EnMCS pay off in the long run. Based on a sample of 236 German manufacturing companies, this study combines primary data that capture the configuration of EnMCS with secondary data that were used to calculate energy efficiency. The results provide evidence that the extent of EnMCS implementation positively relates to firms’ energy efficiency. Findings from additional moderation analysis suggest that companies might enhance the relationship of EnMCS and energy efficiency performance by establishing a full‐time energy manager or by using external energy consulting support.  相似文献   

8.
  总被引:2,自引:0,他引:2  
The quantification and achievement of eco-efficiency or dematerialization in the form of a factor X, with X varying between 4 and 50 is being espoused by a variety of analysts and advocates. Politically, these efforts are mainly confined to some European countries. They reflect a remarkable technological optimism. This article reviews some of the major issues pertinent to the factor X debate. The case is presented for quantifying dematerialization or eco-efficiency goals using a factor X. It is also found that the factor X lacks precision as yet, and that there is only limited interest in the possibilrty that achievable values for X may vary widely among economic activities given technological constraints. There is no agreement whether technological improvement alone will be sufficient to achieve a factor X in practice for economies as a whole. It seems likely, however; that government-driven technology forcing will be necessary to achieve a factor X in practical terms, especially when X is relatively large.  相似文献   

9.
Animals exposed to anthropogenic disturbance make trade-offs between perceived risk and the cost of leaving disturbed areas. Impact assessments tend to focus on overt behavioural responses leading to displacement, but trade-offs may also impact individual energy budgets through reduced foraging performance. Previous studies found no evidence for broad-scale displacement of harbour porpoises exposed to impulse noise from a 10 day two-dimensional seismic survey. Here, we used an array of passive acoustic loggers coupled with calibrated noise measurements to test whether the seismic survey influenced the activity patterns of porpoises remaining in the area. We showed that the probability of recording a buzz declined by 15% in the ensonified area and was positively related to distance from the source vessel. We also estimated received levels at the hydrophones and characterized the noise response curve. Our results demonstrate how environmental impact assessments can be developed to assess more subtle effects of noise disturbance on activity patterns and foraging efficiency.  相似文献   

10.
Domestic Water Use in the United States: A Life-Cycle Approach   总被引:1,自引:0,他引:1  
Water and energy are two primary natural resources used by building occupants. A life-cycle assessment (LCA) is performed for water-consuming plumbing fixtures and water-consuming appliances during their operational life for four different building types. Within the cycle studied, water is extracted from the natural environment, subjected to water treatment, pumped to buildings for use, collected for wastewater treatment, and discharged back to the natural environment. Specifically, the impacts of water use, electricity and natural gas generation, energy consumption (for water and wastewater treatment, and for water heating), and the manufacture of water and wastewater treatment chemicals are evaluated both quantitatively and qualitatively on a generalized national level in the United States of America.
It is concluded that water use and consumption within buildings have a much larger impact on resource consumption than the water and wastewater treatment stages of the life cycle. To study this more specifically, the resource consumption of four different building types-an apartment building, a college dormitory, a motel, and an office building-is considered. Of these four building types, the apartment has the highest energy consumption (for water and wastewater treatment, and for water heating) per volume of water used, whereas the office building has the lowest. Similarly, the calculated LCA score for the apartment building is typically greater than those of the other three building types.  相似文献   

11.
Unsustainable private consumption causes energy and environmental problems. This occurs directly (resource depletion and emissions through using cars for transport) or indirectly (purchase of consumer goods and services for which the production uses energy and emits damaging gases). A hybrid energy analysis proved that indoor energy consumption, mobility, and vacations are the main consumer categories from an energy point of view. Although energy is often used as a proxy for environmental load from private consumption, there are other proxies like methane (CH4), sulfur oxides (SOx), and land use. This article describes the results of the extension of the hybrid energy analysis with energy and ten environmental stressors (CH4, nitrous oxide [N2O], nitrogen, phosphate, SOx, nitrogen oxides [NOx], ammonia [NH3], nonmethane volatile organic compounds [NMVOCs], particulate matter [PM10], and land use), combined in five impact categories (global warming potential [GWP], acidification, eutrophication, summer smog, and land use). Household consumption was analyzed by dividing Dutch household expenditure into 368 consumer items in 11 categories. The results show that food impacts, in particular, are underestimated when only energy is taken into account. Food makes the highest contribution in three out of five impact categories when all ten stressors are taken into account. Within the food domain, meat and dairy consumer items have the highest environmental impact, about 45% of total food impact on average across all five impact categories. Looking in detail (368 consumer items), there are nine food items in the top ten most‐polluting items. Salad oil and cheese are the most polluting food items.  相似文献   

12.
  总被引:1,自引:0,他引:1  
This article investigates technological opportunities to close technospheric flows in a large-scale use of a toxic and scarce metal, lead. It analyzes the lead flows and losses to the environment in a modeled lead-acid battery system for Sweden. The modeled system is built on today's technology for production and recycling of lead and batteries while the recovery of used batteries is varied. The analysis shows that the losses from the production and recycling processes are so low that consumption losses and the recovery rate dominate the total system losses. In a steady state with very high recovery of used batteries, the system losses are small compared to natural lead flows and to the historical lead losses during the industrialization. The modeling assumes that all the secondary lead goes back into the production of new batteries even though in Swedish battery manufacturing today, primary lead dominates the lead supply for lead oxide production. The possibilities for increased secondary lead use in the production of lead oxide are also discussed  相似文献   

13.
    
Feed represents a substantial proportion of production costs in the dairy industry and is a useful target for improving overall system efficiency and sustainability. The objective of this study was to develop methodology to estimate the economic value for a feed efficiency trait and the associated methane production relevant to Canada. The approach quantifies the level of economic savings achieved by selecting animals that convert consumed feed into product while minimizing the feed energy used for inefficient metabolism, maintenance and digestion. We define a selection criterion trait called Feed Performance (FP) as a 1 kg increase in more efficiently used feed in a first parity lactating cow. The impact of a change in this trait on the total lifetime value of more efficiently used feed via correlated selection responses in other life stages is then quantified. The resulting improved conversion of feed was also applied to determine the resulting reduction in output of emissions (and their relative value based on a national emissions value) under an assumption of constant methane yield, where methane yield is defined as kg methane/kg dry matter intake (DMI). Overall, increasing the FP estimated breeding value by one unit (i.e. 1 kg of more efficiently converted DMI during the cow’s first lactation) translates to a total lifetime saving of 3.23 kg in DMI and 0.055 kg in methane with the economic values of CAD $0.82 and CAD $0.07, respectively. Therefore, the estimated total economic value for FP is CAD $0.89/unit. The proposed model is robust and could also be applied to determine the economic value for feed efficiency traits within a selection index in other production systems and countries.  相似文献   

14.
    
Materials flow analysis (MFA) generates highly aggregated indicators for the material \"scale\" of national economies. Similarly, transport statistics operate with indicators for the scale of freight transport activity. This article presents a model that seeks to predict the scale of freight transport from material flows. In the first part, the model MEFASPACE is developed conceptually and formally, as a linear and static (\"mechanistic\") model linking biophysical variables by defined causalities (\"white box\"). The key prediction is that transport volume (TV in metric tons) relates to direct material input (DMI) by a reloading factor, which, for thermodynamic reasons, varies very little. Transport work (TW in metric ton kilometers), the most common indicator for transport activity, depends on TV and distance per haul. In a second part, we probe this model with transport statistics from European countries for the past four decades. Whereas for road and rail transport statistical indicators exist for many countries and years and comply with our model's theoretical definitions, they are either lacking or not complying well for other modes. The results were encouraging, nevertheless. In the past four decades, DMI corresponded very closely to TV as predicted, with a reloading factor that is in the expected range (1–3) and fairly stable across countries and time. At the same time, distances per haul showed a much more dynamic pattern, with quite a bit of variation between countries and a clear tendency to increase over time. Thus, MFA opens a new path for projections and scenario building for freight transport, but needs to be coupled to knowledge from other fields to generate a full picture of transport distances and, finally, environmental pressure.  相似文献   

15.
Population and per capita gross domestic product (GDP) projections are used to estimate total global municipal solid waste (MSW) generation over the twenty‐first century. Some projections for global population suggest that it will peak this century. Waste generation rates per capita generally increase with affluence, although in the most affluent countries there is also a trend toward dematerialization. The confluence of these factors means that at some point in the future total global waste generation could possibly peak. To determine when peak waste might occur, we used the shared‐socioeconomic pathway scenarios (used in Intergovernmental Panel on Climate Change [IPCC] studies) combined with estimates of municipal solid waste (MSW) generation rates, extrapolated from our work for the World Bank. Despite the expectation that total MSW generation in Organisation for Economic Co‐operation and Development (OECD) and high‐income countries will peak mid‐century, with current trajectories global peak waste is not expected before 2100. The peak could be moved forward to around 2075 and reduced in intensity by some 30% if a more aggressive sustainability growth scenario were followed, rather than the current business‐as‐usual scenario. Further, the magnitude of peak waste is sensitive to the intensity of waste generation; it could vary from 7.3 to 10.9 megatonnes per day under the sustainability scenario. The timing of peak waste will substantially depend on the development of cities in Sub‐Saharan Africa, where population growth rates are more than double the rest of the world.  相似文献   

16.
This article examines the emergence of offshore renewable energy (i.e., offshore wind, ocean, and tidal energy) in the Asia-Pacific region with a particular focus on developments in China, South Korea, Australia, and New Zealand. It outlines plans for the development of offshore wind, tidal, and wave energy projects as well as emerging legal and policy measures supporting the growth of offshore renewable energy in the region. The article highlights that, although some progress has been made on laws and other measures to facilitate offshore renewable energy in the Asia-Pacific region, clear regulatory frameworks are still emerging in these jurisdictions.  相似文献   

17.
The Orangi river is an important all-year source of water for wildlife in the northern part of the Serengeti National Park. At two points along the river in the Banagi area, tributaries draining the adit and tailings of the Kilimafeza mine impact the Orangi. The former Au-Cu mine is subject to occasional wet season flooding leading to the release of iron ochres from the adit and physical as well as chemical mobilization of tailings material. The unpolluted river chemistry is essentially Na-Ca-HCO3 and well-buffered. Drainage water; from the tailings are characterized by low pH (2.3) and high concentration of sulphate (up to 3280 mg/l), aluminium (275 mg/l), arsenic (324 mg/l), copper (125 mg/l), iron (622 mg/l), lead (21 mg/l), manganese (65 mg/l), and zinc (126 mg/l). Adit-drainage waters are typically of a lower pH (4.6) and have a lower concentration of sulphate (up to 1840 mg/l) and metals (up to 25 mg/l Al, 92 mg/l As, 42 mg/l Cu, 258 mg/l Fe, 9.6 mg/l Pb, 53 mg/l Mn, and 102 mg/l Zn). Mixing of these acidic waters with the alkaline river leads to rapid metal precipitation as Fe-ochre coatings on clastic sediment. This effect is more noticeable in the dry season. Consequently, although the tributaries draining the two sources are heavily contaminated, the effective buffering of the mine drainage waters restricts any potential pollution to within 1 km of the mine workings. Faecal coliforms show an antipathetic relationship to low pH and high metal conditions. The only mobile metals in the water outside this area are Mn and Zn and their contamination can be biologically monitored using a protozoan-based bioassay.  相似文献   

18.
    
Recent research has found an inverted U relationship between freshwater use and income after controlling for freshwater availability, the structure of the economy, and several policy variables. This suggests that the intensity of freshwater use must be declining with income growth. This hypothesis is tested by developing a simple, informal model of the determinants of freshwater-use intensities across countries and over time. Results suggest that water-use intensity declines across the entire range of per capita incomes extant in the world today. They also show that the relationship between intensity of use and income is mediated by an economy's natural water endowment, the structure of the economy, and government policies. Four policies, in particular, affect the water-use intensity of economies. Open trade policies and tough environmental regulatory policies lower water use intensities, and narrowly defined food self-sufficiency policies and socialist development policies increase water-use intensities. These findings suggest that those interested in water, water scarcity, and water policy need to extend beyond simple extrapolations of past consumption patterns and narrowly focused water policies (such as water pricing) if they want to improve water management practices.  相似文献   

19.
    
To the extent that environmental impacts are the consequence of the magnitude of total material input into production in an economy, they can be lessened by reducing the use of materials—by concentrating on what has been called qualitative growth. This article presents a summary of Finnish resource use over the period 1960–1996 as a means of evaluating the trends in material use and providing a basis for assessments of sustainability. It adapts the technique of decomposition analysis developed in the field of energy studies to distinguish the effects of changes in aggregate economic activity (\"activity effect\"), composition of industrial activity (\"structural effect\") and materials intensity of use (\"intensity effect\") on a sectoral basis.p
According to the analysis presented here, materials consumption in Finland has grown substantially between 1960 and 1996 in the electricity, gas and water supply, pulp and paper production, civil engineering, and mining and quarrying sectors. In the same period, the ratio of GDP/mass of material mobilized has improved by 175 percent. Economic growth has caused the largest increases in materials use in the building of infrastructures; for example roads, waterways, means of supplying electricity, gas, and water, and in the production of paper and paper products. The least growth took place in the transport, basic metals production, and mining and quarrying sectors.  相似文献   

20.
    
The Imperial Chemical Industries (ICI) group has developed a method, called the “environmental burden system” to rank the potential environmental impacts of its emissions and wastes. The method uses potency factors to characterize the potential environmental impacts of wastes and emissions in ten major impact categories. When compared to the more traditional approach of reporting the total mass of emissions and wastes, the environmental burden approach provides a more meaningful picture of the potential impact of emissions: it helps identi?. the most harmful wastes and emissions; it provides the public with a better understanding ofthe potential impact of company operations: and it helps communicate the effectiveness of waste and emission reduction programs  相似文献   

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