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1.
This work performs a comparative life cycle assessment (LCA) of two fuels for heating boilers, namely wood chips and oil. The LCA methodology allows comparing the environmental impacts of the two analyzed fuels, thus assessing which is environmentally more advantageous. The study is focused on Mediterranean forests located in the Argençola region (Catalonia, northeastern Spain) by applying forest management practices focused to ensure a sustainable exploitation. The direct use of wood chips as a fuel for boilers simplifies notably the number of processes involved in producing such a fuel. The results presented clearly show the environmental benefits of using small-scale produced wood chips instead of fossil oil by analyzing representative impact categories defined by the CML and EDIP methods, even when considering the changes in the carbon stock in the forests under analysis due to the management approach adopted. A sensitivity analysis has also been conducted to assess the impact of the data with higher uncertainty on the final LCA results.  相似文献   

2.
This paper presents an analysis of the effect of enhanced research and development (R&D) efforts for a set of low-carbon power technologies on the development of the European energy sector. It applies a methodology using the concept of Two-Factor-Learning, which quantitatively links trends in technology cost to both accumulated R&D investments and production volumes. The impacts of the latter on the energy sector are then simulated in a consistent manner with the POLES global energy model. On this basis, it compares the total system costs of an assumed increase in worldwide R&D investments that for the EU are in line with proposals made in its European Strategic Energy Technology Plan to a baseline development. It finds that an increase in research efforts at a global level will contribute to reducing the costs of currently less mature low-carbon technologies, thus accelerating their market entry. When comparing two scenarios that both fulfil the EU's 2020 energy and climate objectives and differing only in their R&D investment levels, the reduced technology costs allow EU support policies for renewables and carbon values to be reduced, and the cumulative (discounted) benefit of the accelerated research efforts is positive in the long term.  相似文献   

3.
This paper describes a new tool to assess the medium- and long-term economic and environmental impacts of large-scale policies. The approach - macro life cycle assessment (M-LCA) - is based on life cycle assessment methodology and includes additional elements to model economic externalities and the temporal evolution of background parameters. The general equilibrium model GTAP was therefore used to simulate the economic consequences of policies in a dynamic framework representing the temporal evolution of macroeconomic and technological parameters. Environmental impacts, expressed via four indicators (human health, ecosystems, global warming and natural resources), are computed according to policy life cycle and its indirect economic consequences. In order to illustrate the approach, two 2005-2025 European Union (EU) energy policies were compared using M-LCA. The first policy, the bioenergy policy, aims to significantly increase energy generation from biomass and reduce EU energy demand for coal. The second policy, the baseline policy, is a business as usual policy where year 2000 energy policies are extended to 2025. Results show that, compared to the baseline policy, the bioenergy policy generates fewer impacts on three of the four environmental indicators (human health, global warming and natural resources) at the world and EU scales, though the results may differ significantly at a regional level. The results also highlight the key contribution of economic growth to the total environmental impacts computed for the 2005-2025 period. A comparison of the results with a more conventional consequential LCA approach illustrates the benefits of M-LCA when modeling the indirect environmental impacts of large-scale policies. The sensitivity and uncertainty analysis indicates that the method is quite robust. However, its robustness must still be evaluated based on the sensitivity and uncertainty of additional parameters, including the evolution of economic growth.  相似文献   

4.
The usefulness of alternative electric energy sources cannot be assessed without considering their operation within the context of the connected electric system. The value of wind and solar power is strongly dependent on the relationship of the times at which power is available to the times of peak load. A load-duration methodology is developed to assess the economic impact of alternative energy sources on the operation and expansion of the entire system. This methodology treats unschedulable generation as a negative load and obtains a modified load duration curve. On the other hand, schedulable or interruptible load can be treated as negative generation in meeting the load. Where the unit size for dispatching is a small fraction of the system, a continuous-function representation is used. Random factors in availability and load are treated statistically. Economic impacts are evaluated as perturbations on present operations.

Differences are found between intermittent energy sources which are correlated with the load, and sources which are random; and between short-term and long-term impacts.

The results indicate that the benefits per unit of the individual alternative-energy devices are greatest for small penetrations. However, at larger penetrations some additional benefits may be derived from the interaction of complementary technologies.

The load-duration methodology is shown to identify the same trends as hour-by-hour dispatch simulation. It is useful for screening potential applications of new technologies to utility systems, or to estimate future cost-of-service rates to co-generators and small power producers.  相似文献   


5.
This paper examines the air quality impact of using distributed generation (DG) to satisfy future growth in power demand in the South Coast Air Basin of Los Angeles, relative to the impact when the demand is met by expanding current central generation (CG) capacity. The impact of decreasing boiler emissions by capturing the waste heat from DGs is not examined. The air quality impacts of these two alternate scenarios are quantified in terms of hourly maximum ground-level and annually averaged primary NOx concentrations, which are estimated using AERMOD. This study focuses on the impact of primary emissions at source–receptor distances of tens of kilometers. We find that the shift to DGs has the potential for decreasing maximum hourly impacts of power generation in the vicinity of the DGs. The maximum hourly concentration is reduced from 25 to 6 ppb if DGs rather than CGs are used to generate power. However, the annually averaged concentrations are likely to be higher than for the scenario in which existing CGs are used to satisfy power demand growth. Future DG penetration will add an annual average of 0.1 ppb to the current basin average, 20 ppb, while expanding existing CGs will add 0.05 ppb.  相似文献   

6.
This paper deals with comparative assessment of the environmental and health impacts of nuclear and other electricity-generation systems. The study includes normal operations and accidents in the full energy chain analysis. The comparison of environmental impacts arising from the waste-management cycles associated with non-emission waste are also discussed. Nuclear power, while economically feasible and meeting 17% of the world's demand for electricity, is almost free of the air polluting gases that threaten the global climate. Comparing nuclear power with other sources for electricity generation in terms of their associated environmental releases of pollutant such as SO2, NOX, CO2, CH4 and radioisotopes, taking into account the full fuel chains of supply option, nuclear power will help to reduce environmental degradation due to electricity generation activities. In view of CO2 emission, the ranking order commences with hydro, followed by nuclear, wind and photovoltaic power plants. CO2 emissions from a nuclear power plant are by two orders of magnitude lower than those of fossil-fuelled power plants. A consequent risk comparison between different energy sources has to include all phases of the whole energy cycle. Coal mine accidents have resulted in several 1000 acute deaths over the years. Then came hydropower, also resulting in many catastrophes and loss of human lives, followed by the oil and gas energy industries, last in the list is commercial nuclear energy, which has had a “bad” press because of the Chernobyl accident, resulting officially in 31 acute fatalities, and at least 145 latent fatalities. The paper offers some findings and conclusions on the role of nuclear power in protecting the global environment.  相似文献   

7.
The aim of this research is to identify and quantify the categories which have the largest environmental impact in the biodiesel production process from Jatropha curcas L oil. The Jatropha curcas L is selected due to its availability in Cuba, so 400 L/d was defined as a functional unit. The valorization analysis was conducted taking into account the conventional Jatropha curcas L oil production. The analysis is conducted based on several factors such as the use of synthetic fertilizers, pesticides, and agriculture wastes. The activities of agriculture and industrial stages are shown. The Life Cycle Assessment is addressed according to the ISO 14040 series, by using the Ecoinvent database 2003 and the Eco-indicator 99 methodology. Based on the obtained results, the environmental performance of the production of biodiesel from Jatropha curcas L oil has a good environmental behavior. The agriculture stage shows the greatest impact due to land use and fossil fuel depletion. In addition, electricity has the highest impact due to respiratory effects from the emission of tiny material particles into the atmosphere.  相似文献   

8.
Present electricity grids are predominantly thermal (coal, gas) and hydro based. Conventional power planning involves hydro-thermal scheduling and merit order dispatch. In the future, modern renewables (hydro, solar and biomass) are likely to have a significant share in the power sector. This paper presents a method to analyse the impacts of renewables in the electricity grid. A load duration curve based approach has been developed. Renewable energy sources have been treated as negative loads to obtain a modified load duration curve from which capacity savings in terms of base and peak load generation can be computed. The methodology is illustrated for solar, wind and biomass power for Tamil Nadu (a state in India). The trade-offs and interaction between renewable sources are analysed. The impacts on capacity savings by varying the wind regime have also been shown. Scenarios for 2021–22 have been constructed to illustrate the methodology proposed. This technique can be useful for power planners for an analysis of renewables in future electricity grids.  相似文献   

9.
This paper has assessed the externalities of biomass for electricity production, and compared them with those of coal. The effects studied have been those on human health, CO2 balance, soil erosion, non-point-source pollution, and employment. The methodology used has been the one developed by the ExternE Project of the European Commission, which has been extended by CIEMAT to cover socioeconomic impacts. A more site-specific methodology for dealing with soil erosion and non-point-source pollution is also proposed. This methodology has been applied to assess the externalities of a proposed biomass power plant in Spain, and also to a hypothetical coal power plant in the same location. In spite of the high uncertainty involved in the assessment, results show that, when externalities are introduced into the cost analysis, the total costs of biomass electricity is lower than that of coal, under the assumptions used.  相似文献   

10.
This paper assesses the macroeconomic impacts in terms of GDP, trade balance and employment of large-scale bioenergy production on surplus agricultural land. An input–output model is developed with which the direct, indirect and induced macroeconomic impacts of bioenergy production and agricultural intensification, which is needed to make agricultural land become available for bioenergy production, are assessed following a scenario approach. The methodology is applied to a case study of Argentina. The results of this study reveal that large-scale pellet production in 2015 would directly increase GDP by 4%, imports by 10% and employment by 6% over the reference situation in 2001. When accounting for indirect and induced impacts, GDP increases by 18%, imports by 20% and employment by 26% compared to 2001. Agricultural intensification reduces but does not negate these positive impacts of bioenergy production. Accounting for agricultural intensification, the increase in GDP as a result of bioenergy production on surplus agricultural land would amount to 16%, 20% in imports and 16% in employment compared to 2001.  相似文献   

11.
Sustainable energy harvesting, such as solar energy, depends increasingly on nanotechnology components. This article will look briefly at the principles of photovoltaic units and elucidate the toxicological aspects of its principal components, namely fullerenes and carbon nanotubes. Through this approach, we address the rebound effect related to health adverse and environmental aspects which is a key issue to be solved when innovating in energy harvesting. The understanding of sustainability in this context is that the technology provides lasting improvement by bringing environmental compatibility along with technological agility, providing major reductions in both material and energy resource use and avoid negative impacts on our environment and health. With the rebound effect we understand the unintended emergence of negative environmental impacts resulting from intentions of improving environmental issues.Sustainable energy-harvesting, such as solar energy, depends increasingly on nanotechnology components. This article provides a brief overview of photovoltaic units and the toxicological aspects of their principal components, namely fullerenes and carbon nanotubes. It will then address the adverse, rebound effects on human health and the environment, the next key issue to be resolved within energy-harvesting innovation. Sustainability in this context, refers to the role of technology in providing lasting improvement through environmental compatibility combined with technological agility that enables major reductions in both material and energy resource use and minimizes negative impacts on health and the environment. The rebound effect, refers to the unintended emergence of negative environmental impacts as a result of remedial actions designed initially to improve the environment.These will be discussed in context with the two major classes of nanomaterials in consumer electronics: fullerenes and carbon nanotubes, which carry a series of properties that make them classifiable as hazardous materials.  相似文献   

12.
Today, many countries are promoting energy efficiency (EE) measures as part of their energy strategy. Among the goals sought with these actions are producing a decoupling between economic growth and energy consumption, reducing the dependence on fossil fuels as a primary energy source, and reducing greenhouse gas emissions. Measuring direct, indirect, and co-benefit effects of EE programs is crucial. However, in the current literature and practice, assessments of EE programs have focused on direct impacts (i.e., impacts whose energy savings can be directly and instantaneously quantified) due to their objectivity and simplicity to put evaluations in a cost-effectiveness framework. Moreover, several assessment methodologies studying the indirect effects of EE programs only focus on identifying the effects and quantifying a proxy of the effects in terms of the number of activities developed or the number of people attending EE training or dissemination events. Some few existing methodologies correctly assess the indirect effects of EE measures, but they often require a significant budget. We propose a new methodology to assess the impacts of EE programs, especially focusing on indirect effects (i.e., long-term effects on energy use), that is suitable for low-budget programs. We focus on those indirect effects having the capability of mobilizing long-term energy savings through transformations in energy markets. We attempt to measure the potential future energy savings that are sustainable in the long term due to a behavioral transformation of energy markets. In order to measure these indirect effects, we use three axes: presence, valuation, and mobilizing capacity. This methodology was applied to 12 EE programs (implemented during 2011 and 2012 in Chile) in order to obtain their indirect impact assessment.  相似文献   

13.
This study presents a comparative analysis of three different energy production process (EPP) scenarios for Turkey. Main goal is to incorporate the prioritization criteria for the assessment of various energy policies for power alternatives, and evaluating these policies against these criteria. The three types of EPPs reviewed in this study are: electricity production from wind farms in the future, existing coal-based thermal power plants and planned nuclear power plants. The analytical hierarchy process (AHP) is utilized to assess the main and sub-factors of EPPs. Main factors such as economic, technical, social and environmental are assigned in first level of the AHP. The importance weights of factors are produced and priority values with realistic numbers are obtained using Fuzzy-AHP Chang’s Model. Priority value for wind energy was determined as two times higher than the others when making the ultimate decision. On aggregate, importance weights of environmental (0.68) and social (0.69) factors make wind power leader. Sub-factors such as public acceptance, waste-emission and environmental impacts cause both nuclear and thermal power to have the lowest priority numbers. Additionally, the CO2 emissions trade was determined to be a very important criterion associated with both economic and environmental factors according to Kyoto Protocol. This study concludes that Turkey’s existing thermal power stations should gradually be substituted by renewable energy options according to a schedule of Turkish energy policies in future.  相似文献   

14.
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.  相似文献   

15.
Increasing the proportion of power derived from renewable energy sources is becoming an increasingly important part of many countries's strategies to achieve reductions in greenhouse gas emissions. However, renewable energy investments can often have external costs and benefits, which need to be taken into account if socially optimal investments are to be made. This paper attempts to estimate the magnitude of these external costs and benefits for the case of renewable technologies in Scotland, a country which has set particularly ambitious targets for expanding renewable energy. The external effects we consider are those on landscape quality, wildlife and air quality. We also consider the welfare implications of different investment strategies for employment and electricity prices. The methodology used to do this is the choice experiment technique. Renewable technologies considered include hydro, on-shore and off-shore wind power and biomass. Welfare changes for different combinations of impacts associated with different investment strategies are estimated. We also test for differences in preferences towards these impacts between urban and rural communities, and between high- and low-income households.  相似文献   

16.
This paper applies the so-called Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM), based on Georgescu-Roegen's fund-flow model, to the Spanish region of Catalonia. It arrives to the conclusion that within the context of the end of cheap oil, the current development model of the Catalan economy, based on the growth of low-productivity sectors such as services and construction, must be changed. The change is needed not only because of the increasing scarcity of affordable energy and the increasing environmental impact of present development, but also because of the aging population. Moreover, the situation experienced by Catalonia is similar to that of other European countries and many other developed countries. This implies that we can expect a wave of major structural changes in the economy of developed countries worldwide. To make things more challenging, according to current trends, the energy intensity and exosomatic energy metabolism of Catalonia will keep increasing in the near future. To avoid a reduction in the standard of living of Catalans due to a reduction in the available energy it is important that the Government of Catalonia implement major adjustments and conservation efforts in both the household and paid-work sectors.  相似文献   

17.
It is very important for electric utility to determine dominant sectors which have more impacts on electricity consumption in national economy system. In this paper, an input-output perspective and methodology is proposed to handle this issue. The input-output table of electricity demand (IOTED) is put forward based on the input-output table of national economy (IOTNE). The relevancy of electricity demand in various sectors is revealed by means of electricity consumption chains (ECCs), which are key components in the IOTED. Besides, a new concept, electricity demand multiplier (EDM), is presented to identify dominant sectors imposing great impacts on electricity demand quantitatively. In order to testify the effectiveness of the proposed methodology, a case based on provincial economy system in China is studied. Dominant sectors are identified and discussed.  相似文献   

18.
Offshore wind power comprises a relatively new challenge for the international wind industry with a demonstration history of around twenty years and a ten-year commercial history for large, utility-scale projects. By comparison to other forms of electric power generation, offshore wind energy is generally considered to have relatively benign effects on the marine environment. However, offshore projects include platforms, turbines, cables, substations, grids, interconnection and shipping, dredging and associated construction activity. The Operation & Maintenance (O&M) activities include the transport of employees by vessel or helicopter and occasional hardware retrofits. Therefore, various impacts are incurred in the construction, operation and decommissioning phases; mainly the underwater noise and the impacts on the fauna. Based on the fact that in many of the aforementioned issues there are still serious environmental uncertainties, contradictive views and emerging research, the present work intents to provide a thorough literature review on the environmental and social impacts of offshore wind energy projects in comparison with the onshore counterparts.  相似文献   

19.
Recently, significant attention has been directed towards the use of exergy analysis in the assessment of thermal and other industrial processes and their environmental impacts since exergy analysis is an effective tool both for achieving efficient energy utilization with minimum (or zero) environmental impact and for understanding environmental issues. In this study, the concepts of exergy analysis and the linkages between exergy and environmental impact are discussed, and several issues regarding the exergies of waste emissions are addressed. Exergy is a measure of the degree of disequilibrium between a substance and its environment. The relations between several measures of environmental impact potential and exergy are investigated by comparing current methods used to assess the environmental impact potential of waste emissions and the exergy associated with those emissions. A case study is presented, to highlight the information revealed using exergy, in which the measures of environmental impact potential considered are the Ontario Ministry of Environment's schedule of industrial air emission limits, and two methods of assessing the environmental costs for air emissions resulting from the combustion of three common fossil fuels: coal, oil and natural gas. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   

20.
This study examines the impacts of energy price changes resulting from different carbon-pricing policies on the competitiveness of selected US energy-intensive industries. It further examines possible industry responses, and identifies and provides a preliminary evaluation of potential opportunities to mitigate these impacts. The industry sectors investigated – steel, aluminum, chemicals and paper – are among the largest industrial users of fossil fuels in the US economy. The results of this examination show that climate policies that put a price on carbon could have substantial impacts on the competitiveness of US energy-intensive manufacturing sectors over the next two decades, if climate regulations are applied only in the United States, and no action is taken to invest in advanced low- and no-carbon technologies. The extent of these impacts will vary across industries, depending on their energy intensities, the mix of energy sources they rely on and how energy is used in production activities (heat and power, feedstock). Of relevance is also the speed and rigor with which industries adopt new technologies and retire (or replace) old ones. Other factors affecting these impacts include an industry's vulnerability to foreign imports and its ability to pass through cost increases to its customers in the face of international market competition.  相似文献   

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