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| 1 |
ID:
108296
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| 2 |
ID:
179678
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| Summary/Abstract |
Countries are making important efforts decarbonising their electricity generation mix. In this context, improving the operational efficiency enables better use to be made by renewables and the grids. However, the location of new capacity might be relevant from the social welfare point of view when private decisions might affect the power system efficiency.
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| 3 |
ID:
176853
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| Summary/Abstract |
In this paper, we estimate volatility spillovers before and after the introduction of a new cable linking different electricity market zones. Using wholesale electricity prices for Sardinia and two neighbouring Italian market zones for the period 2005–2015, we focus on the effects of the SAPEI cable, fully operational since March 2011. VAR-GARCH estimates indicate that the SAPEI cable allowed for stronger volatility transmission towards Sardinia, a smaller zone and a net importer from its new neighbour, the Central Southern zone, albeit the effect was significant only off-peak. Higher conditional correlations between zonal prices are also observed after the cable was introduced. Some implications are drawn about the interaction between market size, export positions, congestion, and volatility transmission.
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| 4 |
ID:
112920
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2012.
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| Summary/Abstract |
This study quantifies the effects of aggregating electric load over various combinations (Aggregation Groupings) of the 10 Federal Energy Regulatory Commission (FERC) regions in the contiguous U.S. Generator capacity capital cost savings, load energy shift operating cost savings, reserve requirement cost savings, and transmission costs due to aggregation were calculated for each Aggregation Grouping. Eight scenarios of Aggregation Groupings over the U.S. were formed to estimate overall system cost. Transmission costs outweighed cost savings due to aggregation for all scenarios and nearly all Aggregation Groupings. East-west transmission layouts had the highest overall cost, and interconnecting ERCOT to adjacent FERC Regions resulted in increased costs, both due to limited existing transmission capacity. This study found little economic benefit of aggregating electric load alone (e.g., without aggregating renewable generators simultaneously), except in the West and Northwest U.S. If aggregation of load alone is desired, small, regional consolidations yield the lowest overall cost. This study neither examines nor precludes benefits of interconnecting geographically-dispersed renewable generators with load. It also does not consider effects from sub-hourly load variability, fuel diversity and price uncertainty, energy price differences due to congestion, or uncertainty due to forecasting errors; thus, results are valid only for the assumptions made.
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| 5 |
ID:
117008
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| Publication |
2012.
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| Summary/Abstract |
Due to the increase in electricity generation capacity in the Netherlands and a new connection policy, transmission system operator (TSO) TenneT expects a significant increase in congestion in the Dutch transmission grid. To manage this, the Dutch government implemented redispatching, a method which is argued in the literature to potentially impose large congestion costs upon the TSO. A quantitative model of the Dutch electricity system was developed in order to evaluate this method. The outcomes were compared to the performance of three alternative congestion management methods. Regardless of the method, congestion costs were found to be substantially lower than in previous studies. Because combined-cycle gas turbines are the marginal generation technology in almost all cases, the costs of up and down regulation do not differ much. Consequently, the redispatching costs for the TSO are expected to be relatively low, and the opportunities for abuse of market power appear to be limited. While all the evaluated methods are effective and economically efficient, they have significantly different welfare effects. Market splitting creates significantly larger welfare effects than the different varieties of redispatching.
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| 6 |
ID:
125499
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2013.
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| Summary/Abstract |
This article presents a quantitative assessment of the need for electricity transmission capacity investments in Germany for 2030. Congestion is analyzed and its possible relief through appropriate grid reinforcements as those described in the Ten Year Network Development Plan (TYNDP) of the European Commission. Congestion is investigated in three scenarios which differ in the location of power resources and the line expansion projects accomplished. Results show that the TYNDP and overlay line projects proposed in 2011 are not sufficient measures to cope with the increasing demand for transmission capacity. The paper also concludes that if power generation resources are moved closer to demand centers grid bottlenecks can be partly relieved by 2030. The introduction of a high-voltage direct current (HVDC) backbone grid does not relieve congestion significantly.
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| 7 |
ID:
187867
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| Summary/Abstract |
We consider a model of network interactions where the outcome of a unit depends on the outcomes of the connected units. We determine the key network link, i.e., the network link whose removal results in the largest reduction in the aggregate outcomes, and examine a measure that quantifies the contribution of a network link to the aggregate outcomes. We provide an example examining the spread of Covid-19 in China. Travel restrictions were imposed to limit the spread of infectious diseases. As uniform restrictions can be inefficient and incur unnecessarily high costs, we examine the design of restrictions that target specific travel routes. Our approach may be generalized to multiple countries to guide policies during epidemics ranging from ex ante route-specific travel restrictions to ex post health measures based on travel histories, and from the initial travel restrictions to the phased reopening.
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| 8 |
ID:
176826
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| Summary/Abstract |
Electricity systems are facing a massive transformation from the replacement of conventional generation technologies by renewables. In this paper, we explore how to make compatible markets principles, economic signals and grid development through the analysis of the grid-related costs associated with the connection of new renewables. Starting from the actual locational patterns of the transmission congestions as baseline, we evaluate the locational impacts, the corresponding network investments and electricity losses associated with the introduction of new renewable (wind and solar) capacity and facing out existent (coal and nuclear) in a real electricity system. Simulated geographical scenarios following the Spanish National Energy and Climate Plan are used to explore up to what extent the potential locations of new generation plants might result in congestions that require relevant grid reinforcements and extra electricity losses, both borne by consumers.
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| 9 |
ID:
164235
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| Summary/Abstract |
This article considers possibility and expediency of using hybrid power plants for new-generation armored weapons and hardware (AWH). The main mobility indicators for AWH items with various hybrid power plants are analyzed. The problems of their development by domestic enterprises are outlined.
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| 10 |
ID:
110321
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2011.
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| Summary/Abstract |
Transmission of data through a signal based approach has been made possible by the broadcasting organizations, but it has come at certain costs. The problem posed by incidences of signal theft induced the member states of World Intellectual Property Organization to create a new international tool in the form of a treaty to tackle this problem. The paper seeks to analyse this in the light of present legal regime where protection is granted to the broadcasting organizations, and whether granting further protection in the form of exclusive rights will serve the interest of developing nations or not. The representatives of developing nations have made it clear that if the treaty is not based on elementary and absolutely necessary rights, it should be abandoned. A study of the treaty makes it clear that the primary purpose of treaty is not to tackle signal theft, which makes its primary agenda ancillary in nature.
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| 11 |
ID:
133079
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2014.
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| Summary/Abstract |
Replacing current generation with wind energy would help reduce the emissions associated with fossil fuel electricity generation. However, integrating wind into the electricity grid is not without cost. Wind power output is highly variable and average capacity factors from wind farms are often much lower than conventional generators. Further, the best wind resources with highest capacity factors are often located far away from load centers and accessing them therefore requires transmission investments. Energy storage capacity could be an alternative to some of the required transmission investment, thereby reducing capital costs for accessing remote wind farms. This work focuses on the trade-offs between energy storage and transmission. In a case study of a 200 MW wind farm in North Dakota to deliver power to Illinois, we estimate the size of transmission and energy storage capacity that yields the lowest average cost of generating and delivering electricity ($/MW h) from this farm. We find that transmission costs must be at least $600/MW-km and energy storage must cost at most $100/kW h in order for this application of energy storage to be economical.
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| 12 |
ID:
150007
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| Summary/Abstract |
Wind speeds in remote areas are sometimes very high, but transmission costs to access these locations can be prohibitive. We present a conceptual model to estimate the economics of accessing high quality wind resources in remote areas to comply with renewable energy policy targets, and apply the model to the Midwestern grid (MISO) as a case study. We assess the goal of providing 40 TWh of new wind generation while minimizing costs, and include temporal aspects of wind power (variability costs and correlation to market prices) as well as total wind power produced from different farms. We find that building wind farms in North/South Dakota (windiest states) compared to Illinois (less windy, but close to load) would only be economical if the incremental transmission costs to access them were below $360/kW of wind capacity (break-even value). Historically, the incremental transmission costs for wind development in North/South Dakota compared to in Illinois are about twice this value. However, the break-even incremental transmission cost for wind farms in Minnesota/Iowa (also windy states) is $250/kW, which is consistent with historical costs. We conclude that wind development in Minnesota/Iowa is likely more economical to meet MISO renewable targets compared to North/South Dakota or Illinois.
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| 13 |
ID:
121270
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| Publication |
2013.
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| Summary/Abstract |
Efforts to plan and site transmission for wind power cannot currently keep pace with wind power development. The very nature of wind power, whether distributed or intermittent, challenges traditional models of electricity grid development. Much of the decision authority for transmission is located at the state level, creating tensions between a system-wide need for transmission capacity and the local nature of planning and implementation. This study identifies and discusses barriers for wind power transmission and highlights the critical role of states and state policies in expanding and transforming the electricity grid to accommodate large scale wind power. Drawing on extensive interview data with energy stakeholders, we present a comparative case study of state-level contexts linking wind and transmission in Montana, Minnesota, and Texas. Stakeholders were found to portray transmission challenges and solutions for wind power based on the character of the local transmission grid, their status as power importer, exporter or self-sufficient state, and the role wind already plays in the power supply.
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| 14 |
ID:
110584
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| Publication |
2011.
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| Summary/Abstract |
Chinese medicine is a medical system that was developed in China over a long period of time and has subsequently spread over the rest of the world, especially over recent decades. This study aims first to identify this medicine and to examine the changes that accompanied its institutionalisation in the People's Republic of China starting in the 1950's, then to set out the continuities and breaking points that have characterised the ways in which it is transmitted, from traditional apprenticeship training to the development of national university syllabuses. It then looks into the way in which Chinese medicine has faced up to biomedicine and sets out a comparative analysis of the paradigms of these two systems, before describing the way in which this exotic medicine has been received and adapted in the West. This makes it possible to grasp the difficulties and issues involved in its globalisation and the increasingly pressing need, from the perspective of university teaching and research, for a more complete, objective and pragmatic approach to studying it.
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| 15 |
ID:
171473
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| Summary/Abstract |
This paper analyzes the recent expansion of transmission lines in Texas, essentially completed in 2013 at a cost of approximately $7 billion. This project was intended to improve access to areas with high wind generation potential and the resulting increase in wind generation reduced fuel costs and emissions from the displaced fossil fuel generators. I find that the value of the resulting emissions reduction from additional wind generation is approximately twice that of the fuel savings. Additionally, when incorporating the value of reduced emissions, increased generation from already existing wind turbines alone could offset about half of the annualized cost of this transmission expansion while using only 2% of the new transmission capacity. Incorporating the value of emissions reductions could make extending transmission lines to access high quality wind resources more viable, especially if production from already-existing wind turbines in the area are being non-trivially curtailed, as was true in this case.
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| 16 |
ID:
088987
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| Publication |
2009.
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| Summary/Abstract |
In this work, we examine the potential advantages of co-locating wind and energy storage to increase transmission utilization and decrease transmission costs. Co-location of wind and storage decreases transmission requirements, but also decreases the economic value of energy storage compared to locating energy storage at the load. This represents a tradeoff which we examine to estimate the transmission costs required to justify moving storage from load-sited to wind-sited in three different locations in the United States. We examined compressed air energy storage (CAES) in three "wind by wire" scenarios with a variety of transmission and CAES sizes relative to a given amount of wind. In the sites and years evaluated, the optimal amount of transmission ranges from 60% to 100% of the wind farm rating, with the optimal amount of CAES equal to 0-35% of the wind farm rating, depending heavily on wind resource, value of electricity in the local market, and the cost of natural gas.
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