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[en] This work addresses a new framework for self-scheduling of an individual price-taker pumped-storage plant in a day-ahead (DA) market. The goal is achieving the best trade-off between the expected profit and the risks when the plant participates in DA energy, spinning reserve and regulation markets. In this paper, a set of uncertainties including price forecasting errors and also the uncertainty of power delivery requests in the ancillary service markets are contemplated. Considering these uncertainties, a new approach is proposed which is called dynamic self-scheduling (DSS). This risk-constrained dynamic self-scheduling problem is therefore formulated and solved as a mixed integer programming (MIP) problem. Numerical results for a case study are discussed.
[en] Highlights: • We investigate unit commitment deploying stochastic and deterministic approaches. • We consider day-ahead markets, its forecast and weekly price based unit commitment. • Stochastic and deterministic unit commitment are identical for the first planning day. • Unit commitment and bidding policy can be based on the deterministic approach. • Robust forecasting models should be estimated based on the whole planning horizon. - Abstract: Pump storage plants are an important electricity storage technology at present. Investments in this technology are expected to increase. The necessary investment valuation often includes expected cash flows from future price-based unit commitment policies. A price-based unit commitment policy has to consider market price uncertainty and the information revealing nature of electricity markets. For this environment stochastic programming models are suggested to derive the optimal unit commitment policy. For the considered day-ahead price electricity market stochastic and deterministic unit commitment policies are comparable suggesting an application of easier implementable deterministic models. In order to identify suitable unit commitment and forecasting policies, deterministic unit commitment models are applied to actual day-ahead electricity prices of a whole year. As a result, a robust forecasting model should consider the unit commitment planning period. This robust forecasting models result in expected cash flows similar to realized ones allowing a reliable investment valuation
[en] Pumped storage power plants have long been used to regulate the production relative variations in consumption, but there is no preliminary pumping power plant in Norway built to regulate on short terms. To increase the knowledge about the possibilities to establish a pumping power plant in Norway, NVE has therefore been made a study of how pumping power can be drawn up and what it costs to build pumped storage plant between already existing magazine. One can not just based on cost and design conclude anything about the potential for pumped storage plant in Norway, but it is a start of a work that might make it easier to assess to what extent this may be possible. (eb)
[en] Norway has great potential for producing pumped-storage hydropower, and the European Union (EU) hope Norway can contribute to Europe's transition to a renewable energy system by serving as a ‘green battery’. This is certainly technically feasible. However, this paper asks whether the green battery idea is politically feasible. The paper analyses four scenarios, three of which Norway serves as a green battery and one domestic. It focuses on decision-makers' and interest groups' positions on new interconnectors from Norway to continental Europe and the United Kingdom (UK), pumped-storage hydropower, and new renewable energy production in Norway. The paper argues that the present policy is characterised by incremental change—decisions about new interconnectors are made on an individual basis. Moreover the paper argues there is little reason to believe that this status quo policy will change based on any of the green battery scenarios in the near term. Still, decision-makers and interest groups are positive, in principle, towards new interconnectors and pumped-storage hydropower. Hence, Norway might become a green battery in the longer term. In the short term, however, a politically feasible contribution from Norway is balancing power through already existing hydropower capacity. - Highlights: ► Norwegian status quo policy is characterised by incremental change. ► Status quo is no likely to be replaced by a green battery scenario in the short term. ► Norway might become the green battery of Europe in the longer term
[en] The use of renewable energy sources has strongly increased in recent years. Because of the high volatility of these sources, an appropriate energy storage capacity as well as the provision of fast and flexible regulating power is necessary. Both can be supplied by pump storage power plants. The pump storage situation is Germany is discussed. The demand of energy storage is roughly estimated and the status quo of pump storage in Germany is described. Pump storage is compared to other storage technologies (compressed air storage, mobile batteries, hydrogen storage and power-to-gas storage) in terms of efficiency, response time and costs.
[en] Individual hydro- and thermal dominated electric power systems often have characteristics which make coordination between such systems inherently desirable. Operation- and design related differences call for interconnecting the two types of systems, e.g. by a 'pump-storage type' interplay between them. In this scheme the hydro-system can provide for required additional peak power and the necessary 'profiles' of production, while the thermal system covers new energy demand by increased energy production on the course of off-peak hours. Since energy represents one of the crucial building blocks in a modern society, all considerations concerning the development of coordinated systems of first of all focused on the functions and the economics efficiency of these systems and second on the technical solutions that have been developed. However, people have realized that they are part of a larger picture and that their well-being cannot be separated from that of nature. Power production from fossil burning and energy used can give about significant adverse environmental effects through emission into atmosphere of SO2, NOx, CO2, and particulates. The environmental aspects has more or less been neglected in the coordination process. Therefore the time in ripe to extend the discussion to include also environmental effects. The true least-cost solution to the utility operation- and planning problem can only be found by a consistent treatment of environmental effects in all steps of this problem. The paper gives an overview of the problem and demonstrates the environmental benefits from hydro-thermal coordination. (Author)
[en] In view of the need to build and maintain the best power generating mix, pumped storage has an important role to play and will remain an important component of power generation capacity in Japan as well because of its capability to flexibly meet fluctuations in daily load. Taking economical efficiency into account, research activities are carried on to give a higher head to component equipment of pumped storage power plants and to increase the output capacity of these plants. Particularly notable is the improvement of reversible pump-turbines to achieve a very high head by introducing two-stage pump-turbines to overcome the limitations of single-stage ones. Studies have also been conducted on providing plant components with adjustable speed capability to give them such value-added elements as an AFC function in pumping and high-efficiency operation during power generation. All these technologies have reached the commercialization stage. In addition, research projects are under way to develop pumped storage systems with underground reservoirs from the standpoint of further improving the economical performance of hydropower in this category. Of these systems, pumped storage with underground sea water reservoirs appears the best option for Japan which is surrounded by the sea on all sides. (author)
[en] This paper applies the multi-pass dynamic programming to the solution of the short term hydrothermal coordination problem considering pumped storage and battery energy storage systems. The algorithm can quickly converge to an optimal generation schedule while achieving the minimum production cost of power systems. Therefore, the effect of pumped storage and battery energy storage system can be studied
[en] On 31 July 2008 there was an inspection of asphalt-concrete sealing of upper reservoir at the pumped-storage hydro power plant Cierny Vah, involving the representatives of Technical and Safety Surveillance and Special Metering Division of Vodohospodarska vystavba, s. p. Bratislava and STRABAG, a.s. Bratislava, the company which repaired the asphalt-concrete sealing in 2001. (author)