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31.
In the U.S., virtually no new coal-fired power plants have been built in recent years. Both industry experts and academics seem to believe that no rational firm will build a new coal-fired plant. Will such a trend continue in the future? To provide insights into this question, we investigate the optimal decision of an electricity company with an irreversible and deferrable opportunity to build either a new coal-fired or natural gas-fired power plant as its new base-load resource. According to our real option analysis, the optimal decision depends on the location. In the case of the eastern U.S., it is optimal to choose a natural gas plant if a firm is given a choice among a new natural gas plant, a new coal plant and deferring the investment. However, contrary to the common sentiment in the industry and academia, building a new coal plant in the western U.S. is still more economical than building a new natural gas plant in the absence of emission pricing. Furthermore, introducing carbon pricing to western U.S. states, as California did, can substantially increase the probability that a firm will optimally choose a natural gas plant over a coal plant.  相似文献   
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33.
为了在实验室中计量厌氧发酵时产生的沼气体积,设计了一种便携式气体体积计量系统,并分析了系统的构成及运行流程,给出了主要硬件及软件设计方法。试验结果表明,该系统结构合理,使用方便,满足实验室测量气体体积的需要。  相似文献   
34.
Recent legislation intended to increase the use of renewable energy sources and lower the amount of carbon dioxide emissions from energy has changed the structure of energy markets. The effect of these policies on carbon-intensive fuel sources is rather obvious. For natural gas, though, the effect is not immediately clear. This letter uses a structural model of natural gas demand to uncover whether these policies have led to increased demand because natural gas is a relatively clean source of energy that couples well with renewables or if these policies have crowded out natural gas on net.  相似文献   
35.
某燃气公司一段埋地高压天然气输送管线某处发生严重破损,为分析失效原因,作者采用宏观形貌分析、扫描电镜分析、化学成分分析、显微组织分析、力学性能检验、Fluent模拟分析等系列方法对该失效管段进行分析。结果表明,与该天然气管近距离平行铺设的自来水供水管道破裂,导致高速水流正面与切向冲刷作用,最终导致天然气管破裂。根据分析结论,提出了预防同类事故发生的建议。  相似文献   
36.
We investigate the effect of energy commodity price movements on market and electricity index returns in Turkey for the periods before, during, and after the year 2008. Although the Turkish economy is highly reliant on oil, we find that oil price does not lead either electricity or market indexes. This might be attributable to sluggish integration of financial markets in Turkey compared to developed markets. Natural gas price leads electricity index in the pre-2008 period. Its significance is reduced following the decline in natural gas usage in electricity production. This suggests that commodity dependence may be driving the link between commodity and asset prices in related sectors.  相似文献   
37.
We focus on identification and estimation of potentially negative environmental impacts of unconventional natural gas extraction on property values in the United States and advance previous research by contributing new data and new identification strategies for isolating these potential impacts. Our study area consists of two counties in Pennsylvania that are home to large amounts of unconventional natural gas extraction but are otherwise isolated from other resource extraction industries or large urban areas. We deploy parametric, semi-parametric, and matching hedonic regression models that include recent quasi-experimental methods and, in contrast to previous research and much popular intuition, we fail to find robust significance that negative environmental externalities of natural gas extraction are manifested in nearby property values. While there may be plausible risks associated with unconventional natural gas extraction, we do not find consistent evidence to suggest that these risks significantly affect nearby property values.  相似文献   
38.
Oil and natural gas reservoirs typically span multiple productive leases so that no owner has rights to the entire stock of resource, resulting in production externalities. Previous literature has examined the effectiveness of government regulation in Texas and Oklahoma in abating these externalities, finding Oklahoma to be more successful in unifying common pools and securing property rights. Using regression discontinuity design, we quantify the impact of regulatory difference between the two states. We find that Oklahoma produces an average of 3361 more barrels of oil over the life of a well, relative to Texas. Given the maturity of the fields in question, the result underscores the continuing importance of addressing common pool externalities even after the primary phase of recovery has largely been completed.  相似文献   
39.
To meet the 2 °C climate target, deep cuts in greenhouse gas (GHG) emissions will be required for carbon dioxide from fossil fuels but, most likely, also for methane and nitrous oxide from agriculture and other sources. However, relatively little is known about the GHG mitigation potential in agriculture, in particular with respect to the combined effects of technological advancements and dietary changes. Here, we estimate the extent to which changes in technology and demand can reduce Swedish food-related GHG emissions necessary for meeting EU climate targets. This analysis is based on a detailed representation of the food and agriculture system, using 30 different food items.We find that food-related methane and nitrous oxide emissions can be reduced enough to meet the EU 2050 climate targets. Technologically, agriculture can improve in productivity and through implementation of specific mitigation measures. Under optimistic assumptions, these developments could cut current food-related methane and nitrous oxide emissions by nearly 50%. However, also dietary changes will almost certainly be necessary. Large reductions, by 50% or more, in ruminant meat (beef and mutton) consumption are, most likely, unavoidable if the EU targets are to be met. In contrast, continued high per-capita consumption of pork and poultry meat or dairy products might be accommodated within the climate targets. High dairy consumption, however, is only compatible with the targets if there are substantial advances in technology. Reducing food waste plays a minor role for meeting the climate targets, lowering emissions only by an additional 1–3%.  相似文献   
40.
International commercial flights (with the exception of flights between countries in European Union including Iceland, Norway and Liechtenstein) are currently not subject to greenhouse gas emission reduction regulation. To formulate effective and efficiency policy to manage greenhouse gas emissions from air transport, policy makers need to determine the emissions profiles of all airlines currently flying into their country or region. In this paper, we use 2012 data on airlines' aircraft characteristics, passenger load and cargo load (obtained from statistics reported by Australian Government Bureau of Infrastructure, Transport and Regional Economics) to estimate the volume and carbon efficiency on each international route flying to and from Australia. This is the first study to use actual passenger and cargo load data to determine the greenhouse gas (specifically CO2) efficiency of airlines operating in the Australian international aviation market. Airlines' CO2 emission profile is dependent on many factors including but not limited to the aircraft used, payload, route taken, weather conditions. Our results reveal that the airlines’ CO2 emission profile is not only dependent on the aircraft used and the number of passengers but also the amount of cargo on each flight.  相似文献   
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