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Retail electricity price savings from compliance flexibility in GHG standards for stationary sources
《Energy Policy》2012
The EPA will issue rules regulating greenhouse gas (GHG) emissions from existing steam boilers and refineries in 2012. A crucial issue affecting the scope and cost of emissions reductions will be the potential introduction of flexibility in compliance, including averaging across groups of facilities. This research investigates the role of compliance flexibility for the most important of these source categories—existing coal-fired power plants—that currently account for one-third of national emissions of carbon dioxide, the most important greenhouse gas. We find a flexible standard, calibrated to achieve the same emissions reductions as a traditional(inflexible) approach, reduces the increase in electricity price by 60 percent and overall costs by two-thirds in 2020. The flexible standard also leads to substantially more investment to improve the operating efficiency of existing facilities, whereas the traditional standard leads to substantially greater retirement of existing facilities. 相似文献
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目的 制备一种在120~200℃内具有多种热致变色行为的不可逆示温涂层,用于快速排查和准确记录电网设备过热故障发生地点.方法 首先以碳酸钴和氯化钴为原料,用简单的溶液法在水中制备了两种钴基热致变色材料.再以有机硅WB300树脂作为成膜物,自制的两种材料和偏钒酸铵作为变色颜料,高速研磨4~5 h,获得变色涂料.通过XPS、XRD、FT-IR和SEM等测试手段对变色材料进行结构和微观形貌表征.于干燥箱加热观察涂层在120~200℃内的热色性,并用色差计和图像处理软件对变色点进行数据化处理.结果 结合XRD、XPS、FT-IR和TG等一系列表征,证明深绿色的三草酸合钴酸钾在130℃变为粉红色的草酸钴,玫瑰红色的磷酸钴铵在180℃变为深蓝色的磷酸氢钴.涂层附着力达到一级,耐冲击性为50 cm未出现涂层破裂,硬度为2H,在120~200℃具有5~6个变色点,并建立了色-温函数模型.结论 成功自制两种钴基热致变色材料.通过配色,成功制备了色差明显的多变色示温涂层,基本物理性能均满足常规涂层国家标准,涂层加热至200℃都变为黑色,不再改变. 相似文献
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With the development of information technology, cloud computing technology has brought many conveniences to all aspects of work and life. With the continuous promotion, popularization and vigorous development of e-government and e-commerce, the number of documents in electronic form is getting larger and larger. Electronic document is an indispensable main tool and real record of e-government and business activities. How to scientifically and effectively manage electronic documents? This is an important issue faced by governments and enterprises in improving management efficiency, protecting state secrets or business secrets, and reducing management costs. This paper discusses the application of cloud computing technology in the construction of electronic file management system, proposes an architecture of electronic file management system based on cloud computing, and makes a more detailed discussion on key technologies and implementation. The electronic file management system is built on the cloud architecture to enable users to upload, download, share, set security roles, audit, and retrieve files based on multiple modes. An electronic file management system based on cloud computing can make full use of cloud storage, cloud security, and cloud computing technologies to achieve unified, reliable, and secure management of electronic files. 相似文献
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采用数值仿真的方法开展了水电机组一次调频贡献电量的影响因素分析,建立了水电机组一次调频仿真数学模型,采用实际电网频率变化过程作为调速器频率输入,分别对调速器在开度模式和功率模式下的一次调频过渡过程进行了仿真计算,分析了调速器参数、水轮机非线性特性及水流惯性时间常数对一次调频贡献电量的影响。通过研究可知: 增大调速器 PID 参数或降低调差率可提升一次调频贡献电量,水轮机在最小水头下一次调频贡献电量明显偏低,调速器开度模式下水轮机水头和负荷变化对一次调频贡献电量的影响更大。而且,水流惯性时间常数 Tw 越大一次调频贡献电量越小。研究成果明确了调速器参数、水轮机特性以及水流惯性对水电机组一次调频贡献电量的影响规律,对水电机组的优化运行具有重要的指导意义。 相似文献
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针对传统水轮发电机动平衡技术存在的不足及工程实践的需求,本文在研究转子系统单平面多测点平衡模型的基础上,建立了"扁平型"水轮发电机转子的单平面多测点加权平衡模型;通过分析动平衡试验中的"过配"、"欠配"现象,提出了能同时满足空转、空载工况下振动要求的单平面多测点加权适中平衡模型;分别从优化理论及工程实践的角度出发,提出了单平面多测点加权平衡模型、单平面多测点加权适中平衡模型的求解策略,并将本文方法应用于湖南省双牌水电站3号机组的动平衡试验,试验结果表明本文方法在工程实践中简单、可行,具有较高的配重精度。 相似文献
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风电大规模接入配电网给系统安全经济运行带来了极大挑战。为充分表征风电随机性和不确定性对系统运行优化的影响,提出了考虑场景聚类的配电网?天然气联合系统双层随机运行优化模型。首先,通过主成分分析法对海量的高维度风电出力场景进行降维,在降维数据的基础上构建了基于分层聚类算法的风电随机场景选取方法,并提出最优聚类类数的确定标准以有效划分风电场景类数。其次,构建了基于分层场景聚类法的配电网?天然气网耦合系统双层随机运行优化模型,从多个时间尺度提高运行方案对风电波动的适应性。同时,引入拉格朗日因子,并提出KKT(Karush-Kuhn-Tucker)理论的等价方程表示方法,将所提随机运行优化模型转化为单层求解。通过算例,将所提方法与现有运行优化策略对比,验证了所提方法的有效性和优越性。 相似文献
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