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991.
The increasing capacity of distributed electricity generation brings new challenges in maintaining a high security and quality of electricity supply. New techniques are required for grid support and power balance. The highest potential for these techniques is to be found on the part of the electricity distribution grid.

This article addresses this potential and presents the EEPOS project’s approach to the automated management of flexible electrical loads in neighborhoods. The management goals are (i) maximum utilization of distributed generation in the local grid, (ii) peak load shaving/congestion management, and (iii) reduction of electricity distribution losses. Contribution to the power balance is considered by applying two-tariff pricing for electricity.

The presented approach to energy management is tested in a hypothetical sensitivity analysis of a distribution feeder with 10 households and 10 photovoltaic (PV) plants with an average daily consumption of electricity of 4.54 kWh per household and a peak PV panel output of 0.38 kW per plant. Energy management shows efficient performance at relatively low capacities of flexible load. At a flexible load capacity of 2.5% (of the average daily electricity consumption), PV generation surplus is compensated by 34–100% depending on solar irradiance. Peak load is reduced by 30% on average. The article also presents the load shifting effect on electricity distribution losses and electricity costs for the grid user.  相似文献   

992.
Best management practices (BMPs) are widely used to mitigate impacts of increased impervious surfaces on stormwater runoff. However, there is limited detailed and up‐to‐date information available on the cost of designing, constructing, and maintaining BMPs over their lifetime. The objective of this study is to analyze BMPs recently constructed by the Virginia Department of Transportation (VDOT) to quantify their total cost per pound of phosphorus removed annually. A motivating factor for the study is recent changes to regulatory guidelines in Virginia which allow for full or partial substitution of purchased nutrient credits in lieu of constructing onsite BMPs to achieve compliance with stormwater quality regulations. Results of the analysis of nine BMPs found their cost ranged from $20,100 to $74,900, in 2014 dollars, per pound ($44,313‐$165,126 per kg) of phosphorus removed. Based on these results and assuming current credit prices procured by VDOT, purchasing nutrient credits is a cost‐effective option for the agency, especially when factoring in the cost of additional right of way for the BMP. Based on this finding, we expect compliance with stormwater quality regulations through credit purchases to become more widely used in Virginia. Moving forward, we suggest more direct tracking of BMP costs to support comparisons between BMP costs across a range of types and conditions to credit purchases for meeting stormwater regulations.  相似文献   
993.
This paper explores the relationship between government spending and environmental quality using panel data for 94 countries for the period 1970–2008. We identify and estimate three distinct channels that comprise the total direct effect of government expenditure on air pollution, namely a marginal effect, an effect conditional on economic growth and an effect conditional on institutional quality. Since adjustment rate of emissions to their equilibrium level is slow due to technological and institutional reasons, we explicitly take into account dynamics by applying appropriate econometric methods. The results demonstrate that there is a significant alleviating direct effect of government expenditure on SO2 and NOx emissions, which increases with the level of economic growth and democracy. However, there is no evidence of a significant effect on pollutants with more global impact on the environment and human health, like N2O and CO2, implying that the adoption of international environmental treaties is required in this case.  相似文献   
994.
A novel process, microwave assisted catalytic wet air oxidation( MW-CWO), was applied for the degradation of H-acid( l-amino8-naphthol-3, 6-disulfonic acid) in aqueous solution, Ni-loaded granular activated carbon (GAC), prepared by immersion-calcination method, was used as catalyst. The results showed that the MW-CWO process was very effective for the degradation of H-acid in aqueous solution under atmospheric pressure with 87.4% TOC (total organic carbon) reduction in 20 min. Ni on GAC existed in the form of NiO as specified by XRD. Loss of Ni was significant in the initial stage, and then remained almost constant after 20 min reaction. BET surface area results showed that the surface property of GAC after MW-CWO process was superior to that of blank GAC.  相似文献   
995.
京津冀地区空气质量跨区域补偿机制欠缺,已成为制约该区域大气污染联防联控的短板.基于投入产出模型,核算了 2017年生产者负责原则与消费者负责原则下京津冀地区大气污染虚拟治理成本,分析了空气质量补偿主体及资金规模.结果发现,京津冀地区污染物排放具有较强的区域关联关系,说明治理大气污染不只要关注本地减排,还要加强不同地区间...  相似文献   
996.
张龙  宋波  黄凤艳  肖乃川  顿梦杰 《环境科学》2022,43(3):1558-1566
为了解湖南锡矿山周边土壤与农产品锑(Sb)含量特征和污染状况,为锑矿区土壤锑污染防治和农田安全利用提供科学依据.以湖南锡矿山为研究区,采集周边不同区域农田土壤及相应农产品,共计193对,通过分析土壤锑含量、基本理化性质和农产品锑含量,研究锑在土壤-农产品系统中迁移和转换特征,并且对土壤及农产品进行安全评估.结果表明,矿...  相似文献   
997.
通过盆栽试验筛选籽粒Cd低积累型小麦品种,为重金属污染耕地安全利用提供技术支撑.试验研究了 119个小麦品种植株各部位分别在1.5 mg·kg-1(低含量)和4.0 mg·kg-1(高含量)Cd污染土壤条件下对Cd的富集和转运特性,并探讨了小麦不同器官Cd含量的相关性和土壤Cd含量与小麦吸收Cd的关系.结果表明:①供试...  相似文献   
998.
对焙烧炉筒体结构进行有限元建模仿真,考虑热应力、压力和重力对筒体结构受力的影响,计算了焙烧炉关键部位的蠕变疲劳寿命,同时探究进气温度、保温层及对流系数等参数的影响。结果表明:热应力是影响结构强度的关键因素;焙烧炉筒体在许用蠕变变形量为5%的情况下,其使用寿命超过设计寿命;在筒体加热过渡段铺设保温层,降低与外界空气对流和提高进气温度,有利于降低筒体应力。  相似文献   
999.
概述了石化行业现场直接作业环节的安全管控现状,分析了现场管控过程中存在的问题。考虑现场安全管理和监督监控的实际需要,设计了石化行业直接作业现场智能化管控系统,并深入研究作业现场违章行为图像识别的关键技术。现场应用表明,系统充分体现了日常管理、实时监控、智能报警、统计分析等方面的便利性和有效性,各类违章行为图像识别准确率达到80%以上,具有一定的推广价值。  相似文献   
1000.
依据《柴油车加载减速烟度排放标准》和《柴油车加载减速工况烟度检测计算机控制试验规程》的要求,开发了柴油车加载减速工况烟度排放测试软件。详细介绍了该测试软件的功能和特点。  相似文献   
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