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41.
尚迪 《价值工程》2015,(2):27-28
飞灰含碳量对火电厂经济运行有重要影响。本文主要研究通过对电厂锅炉燃烧方式的运行调整提高锅炉的效率和经济性的措施和方法。  相似文献   
42.
Forest management affects the quantity of CO2 emissions in the atmosphere through carbon sequestration in standing biomass, carbon storage in forest products and production of bioenergy. The main question studied in this paper is whether forest carbon sequestration is worth increasing at the expense of bioenergy and forest products to achieve the EU emissions reduction target for 2050 in a cost-efficient manner. A dynamic cost minimisation model is used to find the optimal combination of carbon abatement strategies to meet annual emissions targets between 2010 and 2050. The results indicate that forest carbon sequestration is a low-cost abatement method. With sequestration, the net present costs of meeting EU carbon targets can be reduced by 23%.  相似文献   
43.
This paper empirically assesses the relevance of information on corporate climate change disclosure and performance to asset prices, and discusses whether this information is priced appropriately. Findings indicate that corporate disclosures of quantitative greenhouse gas (GHG) emissions and, to a lesser extent, carbon performance are value relevant. We use hand‐collected information on quantitative GHG emissions for 433 European companies and build portfolios based on GHG disclosure and performance. We regress portfolios on a standard four factor model extended for industry effects over the years 2005 to 2009. Results show that investors achieved abnormal risk‐adjusted returns of up to 13.05% annually by exploiting inefficiently priced positive effects of (complete) GHG emissions disclosure and good corporate climate change performance in terms of GHG efficiency. Results imply that, firstly, information costs involved in carbon disclosure and management do not present a burden on corporate financial resources. Secondly, investors should not neglect carbon disclosure and performance when making investment decisions. Thirdly, during the period analysed, financial markets were inefficient in pricing publicly available information on carbon disclosure and performance. Mandatory and standardised information on carbon performance would consequently not only increase market efficiency but result in better allocation of capital within the real economy.  相似文献   
44.
我国农作物秸秆综合利用现状及焚烧碳排放估算   总被引:19,自引:0,他引:19  
[目的]为加快推进秸秆资源化利用工作,有效缓解因秸秆焚烧带来的环境问题。[方法]将全国划分为黄淮海区、西北区、东北区、东南区、西南区五大区域,对各类农作物秸秆进行了统计分析,研究了秸秆产生量、秸秆资源密度、秸秆利用结构、秸秆焚烧碳排放量。[结果]全国秸秆理论资源量达到10.4亿t,可收集量达到9.0亿t,玉米、水稻和小麦3类农作物秸秆占总量的79.19%,黄淮海区秸秆产量最高,占总量的33.41%。秸秆已利用量为7.21亿t,综合利用率达到80.11%,其中肥料化、饲料化、基料化、燃料化、原料化利用量占已利用量的比例分别为53.93%、23.42%、4.98%、14.27%、3.40%,形成了农用为主的利用格局,但不同秸秆种类综合利用率和利用结构存在显著差异。全国秸秆资源密度和人均占有量分别为523.57kg/667m~2和1.75 t,东北区显著高于全国平均水平,西南区和东南区则显著低于全国平均水平。根据环保部卫星遥感监测的露天焚烧火点数比例估算,2015年我国秸秆露天焚烧量约为8 110万t,总碳排放量约为3 450万t,其中东北地区约占74.1%。[结论]我国秸秆综合利用的重点和难点在东北地区,进一步推动区域秸秆实现全量利用,对于促进低碳农业发展,应对气候变化有着十分重要的意义。  相似文献   
45.
Global leaders agree on the need to substantially decarbonize the global economy by 2050. This paper compares potential costs associated with different policy pathways to achieve tourism sector emission reduction ambitions (?50% by 2035) and transform the sector to be part of the mid-century decarbonized economy (?70% by 2050). Investment in emissions abatement within the tourism sector, combined with strategic external carbon offsets, was found to be approximately 5% more cost effective over the period 2015–2050 than exclusive reliance on offsetting. The cost to achieve the ?50% target through abatement and strategic offsetting, while significant, represents less than 0.1% of the estimated global tourism economy in 2020 and 3.6% in 2050. Distributed equally among all tourists (international and domestic), the cost of a low-carbon tourism sector is estimated at US$11 per trip, equivalent to many current travel fees or taxes. Exclusive reliance on offsetting would expose the sector to extensive and continued carbon liability costs beyond mid-century and could be perceived as climate inaction, increasing reputational risks and the potential for less efficient regulatory interventions that could hinder sustainable tourism development. Effective tourism sector leadership is needed to develop a strategic tourism policy framework and emission measurement and reporting system.  相似文献   
46.
ABSTRACT

Low-carbon mobility (LCM) features strongly in debates about the sustainability of cities and their resilience in the face of demographic, economic, and climate change. Transport is a major source of carbon emissions and there are indications that these continue to increase, despite the considerable recent advances in vehicle, engine, and fuel technologies. Reducing carbon emissions from transport may become more difficult, not easier. A particular issue relates to the New World cities, typified by those of North America and Australasia, which largely developed from the latter half of the nineteenth century onward and whose transportation systems were largely based around private vehicle ownership and usage. These cities are typically composed of low-density, dispersed suburbs, which are highly car dependent and resource and carbon emission intensive. This article develops a research agenda directed at determining and testing policy and planning measures relevant to the quest for low carbon mobility in New World cities. It suggests a rich agenda for essential research on LCM. Much of this agenda falls within the realm of the integration of transport and land use, with attention to urban design details to enhance the perceptions of and opportunities to use low carbon transport alternatives. Research topics identified for LCM research include (1) urban design and land use–transport integration (LUTI), (2) low carbon mobility policies directed at achieving widespread behavior change, (3) opportunities for new technology and its application, including requirements for systems and infrastructure, and (4) analysis and tools for informed decision making, including modeling, measurement, visualization, and especially assessment.  相似文献   
47.
研究目的:从系统角度分析土地、人口、社会、经济、能源对碳排放的影响作用,并对武汉市2017—2030年不同政策情景下的土地利用碳排放进行模拟,为其低碳发展战略和低碳土地利用规划提供决策依据。研究方法:系统动力学方法。研究结果:(1)建立的城市土地利用碳排放系统动力学模型是有效的;(2)按照目前的发展趋势,武汉市的碳排放总量将保持逐年攀升的趋势;(3)经济的快速发展对武汉市土地利用碳排放量的增加具有显著的影响作用;(4)调整土地利用结构、调整产业结构以及提高能源利用效率都能够有效的减少武汉市土地利用碳排放量,其中调整土地利用结构和调整产业结构的作用效果相对来说更加明显。研究结论:转变经济增长方式、升级产业结构、调整土地利用结构和积极研发先进的低碳科学技术是武汉市低碳发展的重要途径。  相似文献   
48.
With corporate disclosure of carbon emissions rapidly increasing, the long-standing question remains whether carbon disclosure has any influence on the improvement of carbon performance. Previous studies of environmental disclosure and performance have predominantly focused on whether disclosure is a substitute for poor performance. Little attention has been devoted to the more important question about how changes in disclosure may lead to subsequent changes in performance over time. Following the rationales taken by the legitimacy and management perspectives, we revisit the relationship between carbon disclosure and performance, with a focus on changes that disclosure may (or may not) create. Using a change analysis of Global 500 companies and their carbon emission and disclosure data released between 2008 and 2012, this study finds that the change in carbon disclosure levels is positively associated with a subsequent change in carbon performance (examined through direct and indirect carbon emission intensities). Thus, regardless of whether disclosure has been used as a legitimising tool for prior poor performance, this study confirms that carbon disclosure motivates companies and creates an ‘outside-in’ driven effect for subsequent change and improvement in carbon performance. However, the association between changes in carbon disclosure and performance is relatively weaker in high energy-intensive firms.  相似文献   
49.
This article proposes a comprehensive framework to explore a possible carbon cap-and-trade scheme in China. By applying the case of China, our empirical results present the demand side and supply side of carbon-emission permits in the market and several other significant findings: (i) carbon dioxide (CO2) marginal abatement cost varies a lot among different regions; (ii) in total, CO2 emissions could have been reduced by 5.14 billion tons if all the provinces had achieved their anticipated environmental performance during 1997–2014; (iii) the equilibrium price of CO2 trading is 241 RMB/ton, irrelevant to the original allocation of allowances.  相似文献   
50.
略论低碳经济的发展向度与意义   总被引:1,自引:1,他引:0  
低碳经济作为一种新的经济形式,无论是理论研究还是实践探索都呼唤发展哲学的观照。低碳经济作为一种新的发展模式,具有鲜明的低代价发展向度、普世的公正发展向度及强烈的创新发展向度,这对于人类社会的持续发展和文明跃迁具有重大而深远的意义。  相似文献   
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