首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 9 毫秒
1.
This article presents an assessment of energy inputs of the European Union (the 15 countries before the 2004 enlargement, abbreviated EU‐15) for the period 1970–2001 and the United States for 1980–2000. The data are based on an energy flow analysis (EFA) that evaluates socioeconomic energy flows in a way that is conceptually consistent with current materials flow analysis (MFA) methods. EFA allows assessment of the total amount of energy required by a national economy; it yields measures of the size of economic systems in biophysical units. In contrast to conventional energy balances, which only include technically used energy, EFA also accounts for socioeconomic inputs of biomass; that is, it also considers food, feed, wood and other materials of biological origin. The energy flow accounts presented in this article do not include embodied energy. Energy flow analyses are relevant for comparisons across modes of subsistence (e.g., agrarian and industrial society) and also to detect interrelations between energy utilization and land use. In the EU‐15, domestic energy consumption (DEC = apparent consumption = domestic extraction plus import minus export) grew from 60 exajoules per year (1 EJ = 1018 J) in 1970 to 79 EJ/yr in 2001, thus exceeding its territory's net primary production (NPP, a measure of the energy throughput of ecosystems). In the United States, DEC increased from 102 EJ/yr in 1980 to 125 EJ/yr in 2000 and was thus slightly smaller than its NPP. Taken together, the EU‐15 and the United States accounted for about 38% of global technical energy use, 31% of humanity's energetic metabolism, but only 10% of global terrestrial NPP and 11% of world population in the early 1990s. Per capita DEC of the United States is more than twice that of the EU‐15. Calculated according to EFA methods, energy input in the EU and the United States was between one‐fifth and one‐third above the corresponding value reported in conventional energy balances. The article discusses implications of these results for sustainability, as well as future research needs.  相似文献   

2.
Based upon the currently emerging international consensus on how to account for the materials flows of industrialized countries, this article proposes methods to account for the energetic metabolism of societies. It argues that, to fully exploit the potential of the metabolism approach in the context of sustainable development, both energetic and material aspects of societal metabolism have to be taken into account. The article proposes concepts to empirically describe energy input, internal energy transformations, and energy utilization of societies by extending commonly used notions of energy statistics in a way that is compatible with current methods of materials flow analysis. Whereas energy statistics include only the energy used in technical devices for providing heat, light, mechanical work, and data processing, an accounting system for the energetic metabolism of societies should also consider flows of nutritional energy for both livestock and humans. Moreover, in assessing the energy input of a society, all inputs of energy-rich materials (and immaterial forms of energy such as electricity and light) that cross the boundary into the biophysical structures of society should be taken into consideration, regardless of the purpose for which they are eventually used. As a consequence, an energetic metabolism accounting system treats all biomass as energy input, instead of considering only the biomass used for technical energy generation, as energy statistics do. Part II in this set of articles will apply these concepts to different modes of societal organization and explore the significance of energetic metabolism for sustainable development. In particular, it will explore the significance for policies that aim at increasing the contribution of renewable energy, especially biomass.  相似文献   

3.
The United States is not only the world's largest economy, but it is also one of the world's largest consumers of natural resources. The country, which is inhabited by some 5% of the world's population, uses roughly one‐fifth of the global primary energy supply and 15% of all extracted materials. This article explores long‐term trends and patterns of material use in the United States. Based on a material flow account (MFA) that is fully consistent with current standards of economy‐wide MFAs and covers domestic extraction, imports, and exports of materials for a 135‐year period, we investigated the evolution of the U.S. industrial metabolism. This process was characterized by an 18‐fold increase in material consumption, a multiplication of material use per capita, and a shift from renewable biomass toward mineral and fossil resources. In spite of considerable improvements in material intensity, no dematerialization has happened so far; in contrast to other high‐income countries, material use has not stabilized since the 1970s, but has continued to grow. This article compares patterns and trends of material use in the United States with those in Japan and the United Kingdom and discusses the factors underlying the disproportionately high level of U.S. per capita resource consumption.  相似文献   

4.
World food production has increased substantially in the past century, thanks mostly to the increase in the use of oil as input in the production processes. This growing use of fossil fuels has negative effects, both on the environment and the production costs. Fishing is a fuel consuming food production activity, and its energy efficiency performance has worsened over time. World‐wide fisheries are also suffering from overexploitation, which contributes to the poor efficiency performance, adding more pressure and criticism on this economic activity. In this paper we analyzed the energy efficiency performance of more than 20,000 European Union (EU) fishing vessels for the period 2002–2008, using the edible energy return on investment (EROI) indicator. The vessels analyzed, grouped in 49 different fleets, represented 25% of the vessels and 33% of the landings of the EU fishing sector. These EU fishing fleets’ average EROI for 2008 was 0.11, which translates to an energy content of the fuel burned that is 9 times greater than the edible energy content of the catch. Hence, the significance of this study arises from the use of time‐series data on a relevant part of the EU fleet that showed stable or even slight improvements on the EROI over time. Moreover, results showed that the energy efficiency of the different fleets varied significantly (from 0.02 to 1.12), mainly depending on the fishing gear and the vessel length. The performance of the most efficient fleets, such as large pelagic trawlers and seiners, was comparable to many agricultural production activities. The plausible drivers behind these trends are further considered.  相似文献   

5.
6.
An analysis of the energy return on investment (EROI) of natural gas obtained from horizontal, hydraulically fractured wells in the Marcellus Shale was conducted using net external energy ratio methodology and available data and estimates of energy inputs and outputs. Used as sources of input data were estimates of carbon dioxide and nitrogen oxides emitted from the gas extraction processes, as well as fuel‐use reports from industry and other sources. Estimates of quantities of materials used and the associated embodied energy as well as other energy‐using steps were also developed from available data. Total input energy was compared with the energy expected to be made available to end users of the natural gas produced from a typical Marcellus well. The analysis indicates that the EROI of a typical well is likely between 64:1 and 112:1, with a mean of approximately 85:1. This range assumes an estimated ultimate recovery (EUR) of 3.0 billion cubic feet (Bcf) per well. EROI values are directly proportionate to EUR values. If the EUR is greater or lesser than 3 Bcf, the EROI would be proportionately higher or lower. EROI is also sensitive to the energy used or embedded in gathering and transmission pipelines and associated infrastructure and energy used for their construction, energy consumed in well drilling and well completion, and energy used for wastewater treatment.  相似文献   

7.
Modeling pathways toward sustainable production and consumption requires improved spatio-temporal and material coverage of end-use product stocks. Momentarily, studies on inflow-driven, dynamic material flow analysis (dMFA) extrapolate scarce information on material end-use shares (i.e., ratios that split economy-wide material consumption to different end-use products) for single countries and years across longer time periods and global regions. Therefore, in part 1 of this work, we reviewed five methods to derive material end-use shares which use industry shipment data in physical units and monetary input–output tables (MIOTs). Herein, we comparatively apply these methods to the United States, drawing on detailed national data, as well as the multi-regional input–output model EXIOBASE3. To better match MIOT and dMFA system definitions, we propose the end-use transfer method, which re-routes specific intermediate outputs to final demand in MIOTs. In closing, we conclude on 12 points for improved end-use shares. We find mixed results regarding the fit between end-use shares derived from industry shipments and MIOTs: for detailed national data, we find good fit for some materials (e.g., aluminum), while others deviate strongly (e.g., steel). In many cases, the temporal trend of MIOT-derived end-use shares roughly agrees with industry shipments. For EXIOBASE3, we find good fit for some countries and materials, but substantial mismatches for others. Despite mixed results, combining MIOT-based end-use shares with industry shipments and auxiliary country-level data could enable improved temporal, geographical, and end-use resolution. However, the scarcity, documentation, and quality of input data are key limitations for more accurate and detailed end-use shares. This article met the requirements for a gold-gold data openness badge described at http://jie.click/badges .   相似文献   

8.
Woody biomass from the southeast United States is expected to play an important role in meeting European Union renewable energy targets. In crafting policies to guide bioenergy development and in guiding investment decisions to meet established policy goals, a firm understanding of the interaction between policy targets and forest biomass markets is necessary, as is the effect that this interaction will have on environmental and economic objectives. This analysis increases our understanding of these interactions by modeling the response of southern US forest markets to new pellet demand in the presence of sustainability sourcing or harvest criteria. We first assess the influence of EU recommended sustainability guidelines on the forest inventory available to supply EU markets, and then model changes in forest composition and extent in response to expected increases in pellet demand. Next, we assess how sustainability guidelines can influence the evolution of forest markets in the region, paying particular attention to changes in land use and forest carbon. Regardless of whether sustainability guidelines are applied, we find increased removals, an increase in forest area, and little change in forest inventory. We also find annual gains in forest carbon in most years of the analysis. The incremental effect of sustainability guideline application on forest carbon and pellet greenhouse gas (GHG) balance is difficult to discern, but results suggest that guidelines could be steering production away from sensitive forest types inherently less responsive to changing market conditions. Pellet GHG balance shows significant annual change and is attributable to the complexity of the underlying forest landscape. The manner by which GHG balance is tracked is thus a critical policy decision, reinforcing the importance and relevance of current efforts to develop approaches to accurately account for the GHG implications of biomass use both in the United States and European Union.  相似文献   

9.
Increased demand for water and energy and growing recognition of environmental issues motivate awareness of how these resources are used in industry. Industrial tomato processing consumes substantial quantities of both water and energy. To understand how these resources are used in tomato processing and what opportunities exist for improving efficiency, a water energy nexus (WEN) assessment was conducted that accounted for the various ways energy becomes embedded in water during processing by motors, pumps, fans, and boilers. The WEN assessment was conducted at an industrial tomato processing facility that processed 265 metric tonnes of fruit per hour to develop a map of water and associated energy use at each processing step. A total of 1.29 billion kilograms (kg) of water were used for the processing season, with 870 million kg routed to flumes. The analysis identified the thermal energy used to generate steam for the various heat exchangers and evaporators used during processing as the greatest source of embedded energy in process water (778,000 gigajoules per season). The electrical energy embedded in the process water totaled 4.4 million kilowatt‐hours per season, over 80% of which was attributed to pumping. Moreover, the data were used to identify opportunities to improve efficiency by adjusting water loads on equipment and developing strategies for water and energy conservation and recovery. The baseline water and energy use data provided by the WEN assessment can enable additional modeling to assess resource efficiency measures and the life cycle impact of processed tomato products.  相似文献   

10.
The present Peru's metabolic profile study poses the specific question, What are the long‐term national energy system implications of the recent government‐supported growth of the mining sector? The question is addressed by analyzing interactions between human economic activity (in hours) and electricity input flows (in joules) in the mining sector of the Peruvian economy in 2000 and 2010, with a projection for 2020. The methodology is based on the multi‐scale integrated analysis of societal and ecosystem metabolism (MuSIASEM), which is an application of Georgescu‐Roegen's bioeconomics approach. Empirical results found for the national economy show: (1) the massive increase in size of the energy system, which is explained by exploitation of the Camisea natural gas (NG) reserves, and (2) the potential for establishing a carbon lock‐in in the electricity sector, owing to increasing construction of electricity plants based on NG as their primary energy source. Empirical results specific to the mining sector indicate: (1) the extremely high electricity metabolic rate of the mining sector (61.6 megajoules per hour in 2010), which was found to be 11 times the rate of electricity used per hour of human activity in the building and manufacturing sector in Peru, and (b) the potential increases in the proportion of electricity used in the mining sector (flow share), which could jeopardize the availability of high‐quality primary energy supplies for the rest of society. In light of these implications, it is argued that the Peruvian government's strong support for growth of the mining sector may have to be reconsidered.  相似文献   

11.
Extended producer responsibility (EPR) policies have proven effective at raising consumer awareness, expanding waste collection infrastructure, and shifting costs of end‐of‐life (EOL) management from municipalities to stewardship organizations. Yet, such policies have been less successful in advancing waste management programs that ensure a net environmental benefit. This article analyzes how EPR policies for single‐use batteries in the European Union (EU), Canada, and the United States address the environmental costs and benefits of EOL management. Considering these EPR policies is instructive, because single‐use batteries have high collection costs and are of relatively low economic value for waste processors. Without deliberate planning, the environmental burdens of collecting and recycling such batteries may exceed the benefits. This article considers how EPR policies for single‐use batteries integrate performance requirements such as collection rates, recycling efficiencies, and best available techniques. It argues that for such policies to be effective, they need to be extended to address waste collection practices, the life cycle consequences of EOL management, and the quality of recovered materials. Such strategies are relevant to EPR policies for other products with marginal secondary value, including some textiles, plastics, and other types of electronic waste.  相似文献   

12.
Industrial ecologists have modeled with precision the material foundations of industrial systems, but given less attention to the demand for products and the drivers of structural changes in these systems. This article suggests that time use data complement data on monetary expenditure and can be used to elucidate the everyday life context in which the changes in the economy take place. It builds upon the claim that goods are not direct sources of utility, but enter specific household activities as inputs. A second argument for the proposed approach is that it can be used to introduce and foster human agency in analyses of production systems. The article uses Finnish time use survey data, consumption expenditure data, and data on the sectoral energy intensities of financial output in the Finnish economy. First, a measure of the energy intensity of activities is derived by relating consumer time use and the required direct and indirect energy requirements. Second, the results include a decomposition of changes in the energy requirements of private consumption in Finland during the 1990s. It is shown that although the same activities on average require increasing energy inputs per unit of time, Finns have simultaneously changed the structure of their everyday life toward less energy-intensive activities.  相似文献   

13.
Urban energy metabolism includes processes for exploiting, transforming, and consuming energy, as well as processes for recycling by‐products and wastes. Embodied energy is the energy consumed during all of these activities, both directly and indirectly. Multiregional input‐output (MRIO) analysis can calculate the energy consumption embodied in flows among sectors for multiple cities or regions. Our goal was to address a problem apparent in previous research, which was insufficient attention to indirect energy flows. We combined MRIO analysis with ecological network analysis to calculate the embodied energy consumption and the energy‐related carbon footprints of five sectors in three regions that comprise the Jing‐Jin‐Ji agglomeration, using data from 2002 and 2007. Our analysis traced metabolic processes of sectors from the perspective of final consumption. Based on the embodied energy analysis, we quantified the indirect energy consumption implied in exchanges of sectors and its distribution and identified the relationships formed through the indirect consumption to analyze the roles of providers and receivers in the system. Results showed that the embodied energy consumption for the Jing‐Jin‐Ji region increased from 2002 to 2007 as a result of increased energy consumption in Tianjin and Hebei. Overall, consumption of Beijing decreased likely attributable to the fact that government policies relocated industries during this time in anticipation of the Olympic Games. The relationships among sectors changed: Beijing changed from a net exporter to an importer, whereas Hebei changed from a net importer of energy from Beijing to an exporter to Beijing, and Tianjin served as an importer in both years.  相似文献   

14.
Military bases resemble small cities and face similar sustainability challenges. As pilot studies in the U.S. Army Net Zero program, 17 locations are moving to 100% renewable energy, zero depletion of water resources, and/or zero waste to landfill by 2020. Some bases target net zero in a single area, such as water, whereas two bases, including Fort Carson, Colorado, target net zero in all three areas. We investigated sustainability strategies that appear when multiple areas (energy, water, and waste) are integrated. A system dynamics model is used to simulate urban metabolism through Fort Carson's energy, water, and waste systems. Integrated scenarios reduce environmental impact up to 46% from the 2010 baseline, whereas single‐dimension scenarios (energy‐only, water‐only, and waste‐only) reduce impact, at most, 20%. Energy conserving technologies offer mutual gains, reducing annual energy use 18% and water use 15%. Renewable energy sources present trade‐offs: Concentrating solar power could supply 11% of energy demand, but increase water demand 2%. Waste to energy could supply 40% of energy demand and reduce waste to landfill >80%, but increase water demand between 1% and 22% depending on cooling system and waste tonnage. Outcomes depend on how the Fort Carson system is defined, because some components represent multiple net zero areas (food represents waste and energy), and some actions require embodied resources (energy generation potentially requires water and off‐base feedstock). We suggest that integrating multiple net zero goals can lead to lower environmental impact for military bases.  相似文献   

15.
Chlorine is an important industrial chemical. Not only is it a component of many important products, it is also needed for many chemical manufacturing processes, even where it does not appear in the final product. But a number of chlorine chemicals, especially organochlorines, are toxic, carcinogenic, tentogenic or otherwise potentially disturbing to the environment. For this reason, some environmentalists—notably Greenpeace-have advocated a ban, not just on some products but on all uses of elemental chlorine. The chemical industry is taking this threat seriously and mounting a vigorous defense. But the debate so far is not illuminating the issues effectively, because both sides are selectively using questionable and unverifiable data.
The scientific uncertainties are not really the problem. Rather, data in the public domain and accessible to environmentalists and even regulatory authorities are of very poor qualrty. Because of industry secrecy much crucial inforrnation is unavailable and some of what is available is misleading or wrong. The dual purposes of this article, and the ones that follow, are (I) to elucidate the information requirements for an adequate life-cycle analysis of chlorine and its uses and (2) to indicate how and where the use of massbalance methodology can help identify errors and fill in gaps.
The present article deals with electrolytic chlorine produdion and mercury flows arising from chlorine production. Subsequent articles deal with conversion processes and losses and further chemical industry uses of chlorine, major end uses of chlorine and chlorine chemicals, and persistent organochlorine pollutants.  相似文献   

16.
The major purpose of this article is to construct a plausible emissions profile for the European chemical industry from process data and mass balance considerations.' In it we describe this industry and its major conversion processes and emissions. Four major process chains, beginning with methane, ethylene, propylene, and benzene are analyzed, along with five important stand-alone processes. A self-consistent version of the industry is constructed for 1992, based on data from a variety of sources.
In 1992 Europe consumed 9,297 metric kilotons as measured by weight of chlorine (kMT[CI]) of salt and 2 I I kMT(CI) of recycled hydrochloric acid (HCI) to produce 86 I0 kMT of virgin elemental chlorine, plus 278 kMT(CI) of virgin by-product HCI. Total chlorine input to the industry was 8,689 kMT including I2 kMT(CI) of recycled chlorinated hydrocarbons (CHCs) and (net) 79 kMT(CI) of HCI. Shipments of chlorine and HCI to other sectors was 1,367 kMT(CI), while 7,322 kMT(CI) was embodied in products or lost within the sector: Of this subtotal, 350 kMT(CI) was used to manufacture identified inorganic chemicals, 5,694 kMT(CI) for identified organic chemicals, and 1,278 kMT(CI) for "other unspecified" chemicals.
We estimate that products account for 41.6% of inputs (measured at the "fence"), while wastes account for 24.7%  相似文献   

17.
In this article we apply geodemographic consumer segmentation data in an input−output framework to understand the direct and indirect carbon dioxide (CO2) emissions associated with consumer behavior of different lifestyles in the United Kingdom. In a subsequent regression analysis, we utilize the lifestyle segments contained in the dataset to control for aspects of behavioral differences related to lifestyles in an analysis of the impact of various socioeconomic variables on CO2 emissions, such as individual aspirations and people's attitudes toward the environment, as well as the physical context in which people act.
This approach enables us to (1) test for the significance of lifestyles in determining CO2 emissions, (2) quantify the importance of a variety of individual socioeconomic determinants, and (3) provide a visual representation of "where" the various factors exert the greatest impact, by exploiting the spatial information contained in the lifestyle data.
Our results indicate the importance of consumer behavior and lifestyles in understanding CO2 emissions in the United Kingdom. Across lifestyle groups, CO2 emissions can vary by a factor of between 2 and 3. Our regression results provide support for the idea that sociodemographic variables are important in explaining emissions. For instance, controlling for lifestyles and other determinants, we find that emissions are increasing with income and decreasing with education. Using the spatial information, we illustrate how the lifestyle mix of households in the United Kingdom affects the geographic distribution of environmental impacts.  相似文献   

18.
Although urban metabolism has been a subject of renewed interest for some years, the related studies remain fragmented throughout the world. Most of them concern major cities (megacities and/or national capitals) and, more rarely, intermediate, medium‐sized or small cities. However, urbanization trends show that together with the metropolization process, another one is characterized by the proliferation of intermediate cities. We have studied the metabolism of two French intermediate cities for the year 2012: Rennes Métropole (400,000 inhabitants) and Le Mans Métropole (200,000 inhabitants). To this end, we used material flow analysis (MFA) based on the methodology developed by Eurostat, adapted to the subnational level. This has been made possible by the use, for the first time, of very precise statistical sources concerning freight. We have developed a multiscale approach in order to weigh the urban metabolism of those two cities and to compare it to other cases and larger territories. This allows a better understanding of the specific territorial metabolism of intermediate cities, their hinterlands, and their logistics‐hub function. We conclude with the “urban dimension” of social metabolism, and, thanks to the multiscale approach, to the debate regarding logistical hubs, dematerialization, and territorial autonomy.  相似文献   

19.
Economic input‐output life cycle assessment (IO‐LCA) models allow for quick estimation of economy‐wide greenhouse gas (GHG) emissions associated with goods and services. IO‐LCA models are usually built using economic accounts and differ from most process‐based models in their use of economic transactions, rather than physical flows, as the drivers of supply‐chain GHG emissions. GHG emissions estimates associated with input supply chains are influenced by the price paid by consumers when the relative prices between individual consumers are different. We investigate the significance of the allocation of GHG emissions based on monetary versus physical units by carrying out a case study of the U.S. electricity sector. We create parallel monetary and mixed‐unit IO‐LCA models using the 2007 Benchmark Accounts of the U.S. economy and sector specific prices for different end users of electricity. This approach is well suited for electricity generation because electricity consumption contributes a significant share of emissions for most processes, and the range of prices paid by electricity consumers allows us to explore the effects of price on allocation of emissions. We find that, in general, monetary input‐output models assign fewer emissions per kilowatt to electricity used by industrial sectors than to electricity used by households and service sectors, attributable to the relatively higher prices paid by households and service sectors. This fact introduces a challenging question of what is the best basis for allocating the emissions from electricity generation given the different uses of electricity by consumers and the wide variability of electricity pricing.  相似文献   

20.
Wastewater treatment infrastructure (WWTI) construction in China has entered an accelerated stage of development in recent years as a result of rapid economic growth, urbanization, and the demand for improving water quality. As a result, a large amount of resources and materials will be allocated for the WWTI, and it is particularly important to find ways to reduce resource consumption effectively so that social dematerialization and sustainable development can be achieved. In this study, we employed the dynamic material flow model to estimate the material flows and stocks of WWTIs and the associated carbon dioxide (CO2) emissions through 2050, considering effects of a rise in water consumption, a longer lifetime, and an increased material recycling rate. Our results indicate that material consumption in WWTIs will increase rapidly through 2025 to meet the needs of the increased volume of discharged wastewater as well as to overcome the shortage of existing wastewater treatment plants. In contrast with the moderate effects of rise in water consumption, prolonging the lifetime will greatly reduce material consumption in WWTI construction during the period 2030–2050, and approximately 60% of the total material input will be saved in the medium‐lifetime scenario, compared with the short‐lifetime scenario. Material output and CO2 emissions associated with WWTIs will be reduced by 87% and 37%, respectively, in the medium‐lifetime scenario, compared with the short‐lifetime scenario, under high‐water‐consumption growth. Our results highlight the great importance of pipeline construction and cement consumption in resource consumption associated with WWTI construction in China. Moreover, this study also examined the potential ways to reduce material consumption in WWTI construction in the context of the demand chain, the design, construction, operation and management, and demolition.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号