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961.
Price volatility analysis has been reported in the literature for most competitive electricity markets around the world. However, no studies have been published yet that quantify price volatility in the Ontario electricity market, which is the focus of the present paper. In this paper, a comparative volatility analysis is conducted for the Ontario market and its neighboring electricity markets. Volatility indices are developed based on historical volatility and price velocity concepts, previously applied to other electricity market prices, and employed in the present work. The analysis is carried out in two scenarios: in the first scenario, the volatility indices are determined for the entire price time series. In the second scenario, the price time series are broken up into 24 time series for each of the 24 h and volatility indices are calculated for each specific hour separately. The volatility indices are also applied to the locational marginal prices of several pricing points in the New England, New York, and PJM electricity markets. The outcomes reveal that price volatility is significantly higher in Ontario than the three studied neighboring electricity markets. Furthermore, comparison of the results of this study with similar findings previously published for 15 other electricity markets demonstrates that the Ontario electricity market is one of the most volatile electricity markets world-wide. This high volatility is argued to be associated with the fact that Ontario is a single-settlement, real-time market. 相似文献
962.
IPTV中EPG模块的设计与优化 总被引:3,自引:1,他引:2
首先介绍了IPTV系统中EPG模块的系统结构和设计方案,然后结合一个终端用户获取热门影片信息的例子说明了EPG的具体实现过程。接着针对实际开发中用户与机顶盒交互可能产生的不可预知的错误,并考虑后期EPG功能的扩展和代码维护,提出了一种基于事务机制的Handler对象的设计和实现方案。实验结果表明,本方案正确可行,有利于系统扩展和维护。 相似文献
963.
Mustafa Safa Kırlı 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2019,41(14):1739-1751
As a developing country, Turkey’s sustainable development objectives converge on robust and sustainable economic development. The increase in its energy and electricity demand is attributed to the growth of population, urbanization, and industrialization parallel to economic and social growth. Instead of fulfilling the obligation to protect the environment arising from international agreements and achieving desired sustainable development, the dependency on imported fossil fuel in electrical energy production and energy-intensive economic growth results in intensified CO2 emission as well as ironically negative economic output. Therefore, Turkey is forced to exploit its indigenous sources such as coal (which unfortunately increases atmospheric Green House Gas “GHG” emissions) and renewable resources. However, high GHG emission – mainly CO2 – of Turkey’s coal power plants impairs deployment of indigenous sources for power generation. Indeed, there is a necessity of technical approaches for higher heat extraction efficiencies and mitigation of high concentration of energy-related CO2 emission. Admittedly, “Carbon Capture, Utilization, and Storage (CCUS)” employing conventional hydrothermal resources offers highly efficient heat extraction, geological CO2 sequestration, and utilization of CO2 for power generation rather than considering CO2 as an effluent. Although there are research gaps and lack of field scale experiment, the economic and environmental viability of implementing CCUS in Turkey can be improved by pilot or field scale projects whereby the presence of these projects commences technological and experimental advances in capturing CO2 either from geothermal power plants or indigenous coal power plants, transporting it to the proven geothermal geologic site, and generating power. Apart from this, the “CO2 – Plume Geothermal Systems (CPG)” compared to unconventional and conventional geothermal systems would commit vigorous potential for continual improvement in economic feasibility of CCUS without a guaranteed return on power generation investments in Turkey. Hence, legislations concerning incentives in CCUS would foster further improvements in the deployment of geothermal resources to pursue sustainable development in Turkey. 相似文献
964.
N. I. Meyer 《Renewable Energy》1998,15(1-4)
Liberalisation of energy markets has been progressing among OECD countries since the early nineties. In Europe this trend was accelerated by the decision in December 1996 by the EU Council of Ministers to adopt a new EU directive on liberalisation of the electricity market. This decision was based on the assumption that a liberalised market with commercial competition would lead to higher efficiency and lower consumer prices. Most EU governments have accepted the new EU directive based on these commercial arguments. Denmark has, however, been in a different situation because its energy policy is based primarily on environmental considerations. Danish energy policy involves government promotion of energy conservation and of systems based on renewable energy sources. This type of policy may in some instances conflict with the principles of the unregulated commercial market.The official Danish target is that 35% of energy demand should be covered by renewables by year 2030. The present paper analyzes the problems and possibilities of meeting this target taking into account the rules of the new EU directive on liberalisation. 相似文献
965.
This paper examines the optimal land allocation for two perennial crops, switchgrass and miscanthus that can be co-fired with coal for electricity generation. Detailed spatial data at county level is used to determine the costs of producing and transporting biomass to power plants in Illinois over a 15-year period. A supply curve for bioenergy is generated at various levels of bioenergy subsidies and the implications of production for farm income and greenhouse gas (GHG) emissions are analyzed. GHG emissions are estimated using lifecycle analysis and include the soil carbon sequestered by perennial grasses and the carbon emissions displaced by these grasses due to both conversion of land from row crops and co-firing the grasses with coal. We find that the conversion of less than 2% of the cropland to bioenergy crops could produce 5.5% of the electricity generated by coal-fired power plants in Illinois and reduce carbon emissions by 11% over the 15-year period. However, the cost of energy from biomass in Illinois is more than twice as high as that of coal. Costly government subsidies for bioenergy or mandates in the form of Renewable Portfolio Standards would be needed to induce the production and use of bioenergy for electricity generation. Alternatively, a modest price for GHG emissions under a cap-and-trade policy could make bioenergy competitive with coal without imposing a fiscal burden on the government. 相似文献
966.
我国经济发展对电耗的影响及电力的需求浅析 总被引:2,自引:0,他引:2
能/电耗的变化与经济发展所处的时期有关。针对我国经济快速发展,从电力角度分析我国工业化进程需经历的三个时期:1949~1979年高度工业重型化时期(工业化初期);1980~2000年高度工业轻型化时期(工业化中期);2001~202X年工业重轻基本协调时期(工业化后期)。由于各时期的特点不同,其能耗电耗也不同。现阶段只有能耗下降超过3%时,电耗才会下降。我国完成工业化进程对电力的需求为:人均用电量达到4500kWh左右,人均发电装机容量达到1kW左右;第二产业用电比重在60%左右,第三产业用电比重高于17%,居民生活用电比重20%左右。 相似文献
967.
968.
The Korean power market is being formed from the unbundled generation, transmission and distribution assets of Korea Electric Power Corporation. The KEPCO generation has been allocated to six independent gencos with a combined generating capacity of 46,629 MW in 2002. This gave an 11% margin over the peak load that year (41,921 MW). 相似文献
969.
970.
基于我国城市住区开发的现实条件,探讨了房地产开发企业资金规模及房地产开发成本双重作用下,城市住区土地开发规模的大小,同时结合南京市土地交易市场成交土地面积的数据分析,指出城市住区土地开发具有分散度大、开发面积小的特征,因此,未来我国应加强小规模、开放住区规划理论的建立和研究。 相似文献