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1.
Through a sensitivity analysis, the trade-off between vehicle range and CO2 emissions is investigated as a function of electric emissions coefficient. Various powertrains were analysed for use in a small crossover sport utility vehicle. Gasoline, gasoline electric hybrid, diesel, fuel cell and battery electric vehicles (BEVs) were considered. Using various upstream fuel pathways and a model for vehicle performance, emissions and energy use were estimated. The hydrogen fuel cell vehicle was found preferable to BEVs under conditions of high CO2 emissions per kW-hr and a high vehicle range requirement. The BEV was preferable for all other conditions.  相似文献   

2.
We estimated carbon dioxide (CO2) and methane (CH4) emissions by diffusion, ebullition, and degassing in turbines from a semi-arid hydropower reservoir in northeastern Brazil. Sampling sites were allocated within the littoral and deeper waters of one embayment, the main-stream, and at turbines. Annual carbon emissions were estimated at 2.3?×?105?±?7.45?×?104 t C year?1, or in CO2-equivalents (CO2-eq) at 1.33?×?106?±?4.5?×?105 t CO2-eq year?1. Diffusion across the water surface was the main pathway accounting for 96% of total carbon emissions. Ebullition was limited to littoral areas. A slight accumulation of CO2, but not of CH4, in bottom waters close to the turbines inlet led to degassing emissions about 8?×?103 t C year?1. Emissions in littoral areas were higher than in main-stream and contribute to 40% of the total carbon. Carbon (C) emissions per electricity generated, at 60% of installed capacity, is 0.05 t C-CO2-eq MWh?1. The ratio increases to 0.09 t C-CO2 MWh?1, equating 80% of the emissions from natural gas and 40% of diesel or coal power plants. Retention time and benthic metabolism were identified as main drivers for carbon emissions in littoral areas, while water column mixing and rapid water flow are important factors preventing CH4 accumulation and loss by degassing. Our results indicate that Itaparica Reservoir, located in the semi-arid region of Northeastern Brazil, acts as a source of GHGs. Management measurements are needed to prevent emissions to raise in the future.  相似文献   

3.
The present study investigates the energy, environment and growth nexus for a panel of South Asian countries including Bangladesh, India, Pakistan, Sri Lanka and Nepal. The simultaneous analysis of real GDP, energy consumption and CO2 emissions is conducted for the period 1980–2010. Levin panel unit root test and Im test panel unit root both indicate that all the variables are I (1). In addition, Kao’s panel Cointegration test specifies a stable long-term relationship between all these variables. Empirical findings show that a 1 % increase in energy consumption increases output by 0.81 % in long run whereas for the same increase in CO2 emission output falls by 0.17 % in long run. Panel Granger causality tests report short-run causality running from energy consumption to CO2 emissions and from CO2 emissions to GDP.  相似文献   

4.
Abandoned peat extraction areas are continuous emitters of GHGs; hence, abandonment of peat extraction areas should immediately be followed by conversion to an appropriate after-use. Our primary aim was to clarify the atmospheric impact of reed canary grass (RCG, Phalaris arundinacea L.) cultivation on an abandoned peat extraction area and to compare it to other after-treatment alternatives. We performed a life-cycle assessment for five different after-use options for a drained organic soil withdrawn from peat extraction: (I) bare peat soil (no management), (II) non-fertilised Phalaris cultivation, (III) fertilised Phalaris cultivation, (IV) afforestation, and (V) rewetting. Our results showed that on average the non-fertilised and fertilised Phalaris alternatives had a cooling effect on the atmosphere (?10,837 and ?477 kg CO2-eq ha?1 year?1, respectively), whereas afforestation, rewetting, and no-management alternatives contributed to global warming (9,511, 8,195, and 2,529 kg CO2-eq ha?1 year?1, respectively). The main components influencing the global warming potential of different after-use alternatives were site GHG emissions, carbon assimilation by plants, and emissions from combustion, while management-related emissions played a relatively minor role. The results of this study indicate that, from the perspective of atmospheric impact, the most suitable after-use option for an abandoned peat extraction area is cultivation of RCG.  相似文献   

5.
Closed landfills need after-closure rehabilitation. The chosen option should ensure greenhouse gases release, from the landfill, is not promoted once settled. The objective of this study was to estimate and confront, during different seasons, CH4, CO2 and N2O emissions under three vegetation covers in a closed landfill in Buenos Aires, Argentina. CH4 (methane), CO2 (carbon dioxide) and N2O (nitrous oxide) emissions from landfill’s technosol under spontaneous vegetation (control), Pennisetum purpureum and Miscanthus giganteus (biomass crops), were quantified with non-steady-state non-flow-through chambers, in July 2014 and from February to July 2015. A linear regression analysis was performed to relate the variables “flux of a gas” and “concentration of that gas” from the 3 treatments and 6 dates, separating the 5 sampling times. A high correlation between concentrations and fluxes of CO2 and N2O was found, but no correlation was established for CH4. Mean emissions (2014–2015) varied from: ?2.3 to 639.41 mgCH4 m?2 day?1, 3884 to 46,365 mgCO2 m?2 day?1 and 0.40 to 14.59 mgN2O m?2 day?1. Vegetation covers had no significant effect on CH4 and N2O concentration in time, but they had on CO2 concentration. Season of the year had a significant effect on concentration of the three gases. This is the first study on CH4, CO2 and N2O emissions from a landfill closed 27 years ago covered with biomass crops.  相似文献   

6.
With the economic development, China has become the largest CO2 emissions country. China’s power industry CO2 emissions accounted for about 50% of total CO2 emissions. Therefore, exploring major drivers of CO2 emissions is critical to mitigating its CO2 emissions in power industry. Many studies considered the time series model to analyze the national influences factors of CO2 emissions. But this paper focuses on regional differences in CO2 emissions and adopts panel data models to explore the major impact factors of CO2 emissions in the power industry at the regional and provincial perspectives. The results indicate economic growth level plays a dominant role in reducing CO2 emissions. The power-consuming efficiency on the demand side has large potential to mitigate CO2 emissions, but its influences are different in three regions. The impacts of the electric power structure on CO2 emissions decline from the eastern region to the central and western regions. The influence of urbanization and industrialization also has significant regional differences. Therefore, the governments should consider the influencing factors and regional differences and formulate appropriate policies to decrease CO2 emissions in the power industry.  相似文献   

7.
This article analyzes the causality between the economic growth, the energy and the environment, measured by CO2 emissions. Our empirical study is based on a series of annual data from 1980 to 2010 in Tunisia. Our study was conducted using the Granger causality test and variance decomposition. The empirical results confirm the presence of a positive effect between the energy consumption and the economic growth measured by gross domestic product (GDP). Thus, there is a unidirectional relationship between GDP and CO2 emissions in the short term. This analysis shows, as is common to relatively fast-growing economies in Tunisia, that the biggest contributor to the rise is CO2 emissions. Hence, in congruence with the result of variance decomposition, the GDP affects CO2 emissions in the short and medium term at an almost constant level (10 %). The non-renewable energy intensity in Tunisian economy is responsible for a modest reduction in CO2 emissions, which suggests the implementation of conservation policies aimed at energy efficiency and the orientation toward renewable energy.  相似文献   

8.
Energy consumption is fundamentally necessary for human well-being. However, although increasing energy consumption provides substantial improvements in well-being for low and intermediate levels of development, incremental increases in consumption fail to provide improvements for “super-developed” countries that exhibit the highest levels of development and energy consumption. The aim of this note is, therefore, to quantitatively explore the global emissions debt and climate change commitment associated with the gap in energy consumption between the energy-saturated super-developed countries and the rest of the world. Adopting Kates’ identity, I calculate that elevating the current populations in the non-super-developed countries to the energy and carbon intensities of the United States is akin to adding the fossil-fuel CO2 emissions of more than 15 United States to the global annual total, implying cumulative emissions of almost 4000 GT CO2 from 2010 through 2050. The inevitability of continued emissions beyond 2050 suggests that the transition of non-super-developed countries to a US-like profile between now and 2050 could, by itself, plausibly result in global warming of 3.2 °C above the late-twentieth century baseline, including an extremely high likelihood that global warming would exceed 1.2 °C. Global warming of this magnitude is likely to cause regional climate change that falls well outside of the baseline variations to which much of the world is presently accustomed, meaning that a US-like energy-development pathway carries substantial climate change commitment for both non-super-developed and super-developed countries, independent of future emissions from the super-developed world. However, the assumption that all countries converge on the minimum energy intensity of the super-developed world and a carbon-free energy system between now and 2050 implies cumulative CO2 emissions of less than 1000 GT CO2 between 2010 and 2050, along with a less than 40 % probability of exceeding 1.2 °C of additional global warming. It is, therefore, possible that intensive efforts to develop and deploy global-scale capacity for low-carbon energy consumption could simultaneously ensure human well-being and substantially limit the associated climate change commitment.  相似文献   

9.
Greenhouse gases (GHG) emissions from agricultural farming practice contribute significantly to European GHG inventories. For example, CO2 is emitted when grassland is converted to cropland or when peatlands are drained and cultivated. N2O emissions result from fertilization. Enabling farmers to reduce their GHG emissions requires sufficient information about its pressure–impact relations as well as incentives, such as regulations and funding, that support climate-friendly agricultural management. This paper discusses potentials to improve the supply of information on: farm-specific climate services or impacts, present policy incentives in Germany and England that support climate-friendly farm management and related adaptation requirements. Tools which have been developed for a farm environmental management software (to be added after review because of potential identification) are presented. These tools assess CO2 emissions from grassland conversion to cropland and peatland cultivation, as well as N2O emissions from nitrogen fertilization. As input data, the CO2 tool requires a classification of soil types according to soil organic carbon storage. The input data based on soil profile samples was compared with reference data from the literature. The N2O tool relies on farm data concerning fertilization. These tools were tested on three farms in order to determine their viability with respect to the availability of required data and the differentiation of results, which determines how well site-specific conservation measures can be identified. Assessing CO2 retention function of grassland conservation to cropland on the test farms leads to spatially differentiated results (~100 to ~900 potentially mitigated t CO2 ha?1). Assessed N2O emissions varied from 0.41 to 1.1 t CO2eq. ha?1 a?1. The proposed methods support policies that promote a more differentiated funding of climate conservation measures. Conservation measures and areas can be selected so that they will have the greatest mitigation effects. However, even though present policy instruments in Germany and England, such as Cross Compliance and agri-environmental measures, have the potential to reduce agricultural GHG, they do not appear to guide measures effectively or site-specifically. In order to close this gap, agri-environmental measures with the potential to support climate protection should be spatially optimized. Additionally, the wetland restoration measures which are most effective in reducing GHG emissions should be included in funding schemes.  相似文献   

10.
Oxidation of hydrocarbon in asphalt binder leads to the production of carbon dioxide (CO2) during the production of hot mix asphalt. The objective of this laboratory study was to investigate the effects of the asphalt additive Sasobit®, asphalt content and mixing/placement temperature on CO2 emissions from binder with laboratory measurements. The isolated effects of Sasobit on asphalt absorption into the aggregate were also looked at. Temperature was found to be the only statistically significant factor on emissions. This would suggest that warm mix asphalt technology, which employs the use of Sasobit in asphalt mixtures, is a very effective way of lowering the industry's CO2 emission impact, both directly and by the use of less energy for heating. This work predicts that greater than 30% reduction of CO2 emissions is possible with typically used levels of Sasobit.  相似文献   

11.
This article considers a planner’s optimum control exercise with environmental pollution and derives a testable link between the growth rates of consumption and pollution. The link is then empirically estimated for the case of CO2 emissions for a sample consisting of the union of top 25 countries in terms of CO2 emissions, population and per capita GNP. The analysis suggests that the interrelationship between the growth rates of CO2 emission and economic development is mostly significant for countries that have a high level of CO2 emissions and population.  相似文献   

12.
Globally, more than 30 % of all food that is produced is ultimately lost and/or wasted through inefficiencies in the food supply chain. In the developed world this wastage is centred on the last stage in the supply chain; the end-consumer throwing away food that is purchased but not eaten. In contrast, in the developing world the bulk of lost food occurs in the early stages of the supply chain (production, harvesting and distribution). Excess food consumption is a similarly inefficient use of global agricultural production; with almost 1 billion people now classed as obese, 842 million people are suffering from chronic hunger. Given the magnitude of greenhouse gas emissions from the agricultural sector, strategies that reduce food loss and wastage, or address excess caloric consumption, have great potential as effective tools in global climate change mitigation. Here, we examine the challenges of robust quantification of food wastage and consumption inefficiencies, and their associated greenhouse gas emissions, along the supply chain. We find that the quality and quantity of data are highly variable within and between geographical regions, with the greatest range tending to be associated with developing nations. Estimation of production-phase GHG emissions for food wastage and excess consumption is found to be similarly challenging on a global scale, with use of IPCC default (Tier 1) emission factors for food production being required in many regions. Where robust food waste data and production-phase emission factors do exist—such as for the UK—we find that avoiding consumer-phase food waste can deliver significant up-stream reductions in GHG emissions from the agricultural sector. Eliminating consumer milk waste in the UK alone could mitigate up to 200 Gg CO2e year?1; scaled up globally, we estimate mitigation potential of over 25,000 Gg CO2e year?1.  相似文献   

13.
A chemical pathway combining reverse water gas shift, Fischer‐Tropsch synthesis and hydro‐cracking was considered to re‐synthesise jet fuel from CO2 captured at high purity by oxy‐fuelling of a typical coal‐fired power station (Drax, UK). The oxygen for oxy‐fuelling and hydrogen for the fuel re‐synthesis process are sourced by electrolysis of water. According to material and energy balances , 3.1 MT/year of jet fuel and 1.6 MT/year each of gas oil and naphtha can be produced from the Drax annual emissions of 20 MT of CO2, sufficient to supply 23% of the UK jet fuel requirements. The overall re‐synthesis requires 16.9 GW, to be sourced renewably from (offshore) wind power, and releases 4.4 GW of exothermic energy giving scope for improvements via process integration. The energy re‐synthesis penalty was 82% ideally and 95% on a practical basis. With the cost of offshore wind power predicted to reduce to 2.0 p/kWh by 2020, this ‘re‐syn’ jet fuel would be competitive with conventional jet fuel, especially if carbon taxes apply. The re‐use of CO2 sequestrated from coal power stations to form jet‐fuel would halve the combined CO2 emissions from the coal power and aviation sectors.  相似文献   

14.
The Welsh Government is committed to reduce greenhouse gas (GHG) emissions from agricultural systems and combat the effects of future climate change. In this study, the ECOSSE model was applied spatially to estimate GHG and soil organic carbon (SOC) fluxes from three major land uses (grass, arable and forest) in Wales. The aims of the simulations were: (1) to estimate the annual net GHG balance for Wales; (2) to investigate the efficiency of the reduced nitrogen (N) fertilizer goal of the sustainable land management scheme (Glastir), through which the Welsh Government offers financial support to farmers and land managers on GHG flux reduction; and (3) to investigate the effects of future climate change on the emissions of GHG and plant net primary production (NPP). Three climate scenarios were studied: baseline (1961–1990) and low and high emission climate scenarios (2015–2050). Results reveal that grassland and cropland are the major nitrous oxide (N2O) emitters and consequently emit more GHG to the atmosphere than forests. The overall average simulated annual net GHG balance for Wales under baseline climate (1961–1990) is equivalent to 0.2 t CO2e ha?1 y?1 which gives an estimate of total annual net flux for Wales of 0.34 Mt CO2e y?1. Reducing N fertilizer by 20 and 40 % could reduce annual net GHG fluxes by 7 and 25 %, respectively. If the current N fertilizer application rate continues, predicted climate change by the year 2050 would not significantly affect GHG emissions or NPP from soils in Wales.  相似文献   

15.
Carbon dioxide (CO2) emission has drawn a great attention in recent years all over the world, and it plays a very important role in the process of global warming. The off-road equipment, which includes construction equipment, accounted for 7.5% emission of CO2. The objective of this article is to propose a groundwork for a methodology that can be used to estimate the total fuel use and CO2 emissions from construction equipment activities based on its productivity rate. Currently, there is not a methodology or technique for estimating productivity, fuel use and emissions at once. The multiple linear regression analysis has successfully modelled the productivity rate and good to be used as a benchmark for estimating fuel use and CO2 emissions from various types of construction equipment performing earthwork activities. The proposed methodology will help the contractor to estimate the total expected pollutant emissions for the project, which would be valuable information for a preliminary environmental assessment of the project. By using construction plans and specifications, the methodology and tool presented in this research can be used to estimate cost, fuel use and emissions from commercial, residential, industrial or heavy highway. By the proposed approach, it is possible to develop new fuel use and emissions inventories for construction industry in general.  相似文献   

16.

The income inequality-economy link has been argued by researchers a long time. But the impact of income inequality on environmental pollution is a new investigation topic for developing countries. Turkey is well known as an emerging economy which has a high level of income inequality and CO2 emissions. Therefore, this paper concentrates on the income inequality-CO2 emissions link in Turkish economy by applying a nonlinear analysis. This paper integrates economic growth and financial development to the CO2 emissions specification over the period of 1987–2019. We employ the nonlinear autoregressive distributed lag approach to explore the long-run nonlinear linkages between the series. Our findings reveal an asymmetric cointegration among variables. Positive and negative income inequality shocks positively affect CO2 emissions implying that positive and negative shocks of income inequality enhance CO2 emissions in the long run. Negative economic growth shocks decrease CO2 emissions, while positive shocks to financial development increase CO2 emissions in the long run. We provide important policy suggestions that might be useful to the policymakers to decrease CO2 emissions in Turkey.

  相似文献   

17.
Abstract

This paper proposes to use DEA models with undesirable outputs to construct the Malmquist index that can be use to investigate the dynamic changes of CO2 emission performance. With the index, the authors have measured the CO2 emission performance of 28 provinces and autonomous regions in China from 1996 to 2007; with the convergence theory and panel data regression model, the authors analyze the regional differences and the influencing factors. It is found that the performance of CO2 emissions in China has been continuously improved mainly due to the technological progress, and the average improvement rate is 3.25%, with a cumulative improvement rate of 40.86%. In addition, the CO2 emission performance varies across four regions. As a whole, the performance score of eastern China is the highest. The northeastern and central China has relatively lower performance scores, and the western China is relatively backward. The regional differences are decreasing, and the performance of CO2 emissions is convergent. The influence of some factors on the performance of CO2 emissions is significant, such as the level of economic development, the level of industrial structure, energy intensity, and ownership structure. The influence of some factors, such as opening-up to the outside world, on the performance of CO2 emissions is not significant.  相似文献   

18.
Dairy feeding systems in many semi-arid countries are based on imported concentrates and forages. This has economic and ecological implications given the increase in global feed prices and greenhouse gas (GHG) emissions from land use change. This paper aims to explore alternative dairy feeding systems under semi-arid conditions, using Jordan as an example. The feedings systems under investigation vary in their share of food industry by-products (replacing concentrates in the diet) and are compared against the current concentrate-based feeding systems. The systems are evaluated against three criteria: their nutritional value, their impact on the cost of milk production, and their GHG mitigation potential. Feed samples from eleven food industry by-products and ten conventional feeds were collected from food factories and from three typical dairy farms, representing the typical large-, medium- and small-scale farm types, respectively. Feed samples were analysed for their chemical composition and metabolisable energy contents. In addition, economic and production farm data were collected and entered into a model for GHGs calculation and economic evaluation. The results suggest that inclusion of locally available food industry by-products in the rations of milk cows in semi-arid production systems can be instrumental in reducing production costs and mitigating GHG emissions. Cost of milk production in the model farms can be lowered by up to 14 %; mitigation of CO2 eq. emission ranged between 70 and 290 g CO2 eq./kg milk. The degree to which these benefits can be reaped is positively related to the level of inclusion of by-product feeds in lactating cows’ diets.  相似文献   

19.
Carbon dioxide emissions due to fossil fuel consumption are well recognized as a major contributor to climate change. In the debate on dealing with this threat, expectations are high that agriculture based economies of the developing world can help alleviate this problem. But, the contribution of agricultural operations to these emissions is fairly small. It is the clearing of native ecosystems for agricultural use in the tropics that is the largest non-fossil fuel source of CO2 input to the atmosphere. Our calculation show that the use of fossil energy and the concomitant emission of CO2 in the agricultural operational sector - i.e. the use of farm machinery, irrigation, fertilization and chemical pesticides - amounts to merely 3.9% of the commercial energy use in that part of the world. Of this, 70% is associated with the production and use of chemical fertilizers. In the absence of fertilizer use, the developing world would have converted even more land for cultivation, most of which is completely unsuitable for cultivation. Current expectations are that reforestation in these countries can sequester large quantities of carbon in order to mitigate excessive emissions elsewhere. But, any program that aims to set aside land for the purpose of sequestering carbon must do so without threatening food security in the region. The sole option to liberate the necessary land for carbon sequestration would be the intensification of agricultural production on some of the better lands by increased fertilizer inputs. As our calculations show, the sequestration of carbon far outweighs the emissions that are associated with the production of the extra fertilizer needed. Increasing the fertilizer use in the developing world (without China) by 20%, we calculated an overall net benefit in the carbon budget of between 80 and 206 Mt yr?1 dependent on the carbon sequestration rate assumed for the regrowing forest. In those regions, where current fertilizer use is low, the relative benefits are the highest as responding yield increases are highest and thus more land can be set aside without harming food security. In Sub-Saharan Africa a 20% fertilizer increase, which amounts to 0.14 Mt of extra fertilizer, can tie up somewhere between 8 and 19 Mt of CO2 per year (average: 96 t CO2 per 1 t fertilizer). In the Near East and North Africa with a 20%-increased fertilizer use of 0.4 Mt yr-1 between 10 and 24 Mt of CO2 could be sequestered on the land set aside (40 t CO2 per 1 t fertilizer). In South Asia this is 22–61 Mt CO2 yr?1 with an annual additional input of 2.15 Mt fertilizer (19 t CO2 per 1 t fertilizer). In fact, carbon credits may be the only way for some of the farmers in these regions to afford the costly inputs. Additionally, in regions with already relatively high fertilizer inputs such as in South Asia, an efficient use of the extra fertilizer must be warranted. Nevertheless, the net CO2 benefit through implementation of this measure in the developing world is insignificant compared to the worldwide CO2 output by human activity. Thus, reforestation is only one mitigating measure and not the solution to unconstrained fossil fuel CO2 emissions. Carbon emissions should, therefore, first of all be reduced by the avoidance of deforestation in the developing world and moreover by higher energy efficiency and the use of alternative energy sources.  相似文献   

20.
This paper compares an existing unreliable grid supply with a proposed PV–biodiesel hybrid energy system in order to find the feasibility of the latter for improvement in reliability of power supply, lower pollutant emissions and saving of coal reserves. In the present study, the electrical load of a cement technology institute located in Bhilai, India, has been selected for the purpose of analysis. The results show that hybrid PV–biodiesel system comprising 25 kW PV array, 8 kW biodiesel generator-1, 20 kW biodiesel generator-2, 10 kW inverter and 10 kW rectifier will supply power to the institute avoiding addition of 27.744 tons of CO2 in atmosphere and save 55,080 kg of coal per year with improvement in reliability from 93.15 to 100%.  相似文献   

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