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Rapid worldwide increase of Variable Generation (VG) brings new challenges for System Operators (SOs) when maintaining power balance and frequency control. SOs can apply different strategies to reach frequency quality goals. However, there is no general framework to compare these strategies in terms of cost. This is important when comparing it with the costs of implementation and costs of market limitations. A contribution is a general setup to evaluate various strategies. To apply this setup, methods to proceb available low-resolution data to high-resolution data are needed. Another contribution is a setup of these data procebing methods. The procebing methods are verified by comparing simulated and measured electric frequencies. Using the verified setup as a reference the proposed evaluation method can be applied. An optimal strategy is one improving frequency quality at lowest pobible cost. The proposed setup is tested using a Nordic Synchronous power system case study. The case study is a strategy change of the Ramping Rate (RR) of Transmibion between Asynchronous Areas (TBAA)., QC 20161213

The main purpose of this paper is to summarize the findings from simulating two stochastic short-term planning models for a price-taker hydropower producer. The first model is a two-stage stochastic linear programming problem. Profound sensitivity analysis is provided in terms of volatility in spot market prices and water inflow level. The results show that for the short-term hydropower planning problems the effect of considering price uncertainty in the stochastic model is higher compared to considering inflow level uncertainty. The second model is a two- stage stochastic linear programming problem. The model generates optimal bids to spot market considering real-time market price uncertainties. While simultaneously bidding to both markets, the results are not realistic. To make the bidding strategies more flexible and robust different approaches are modeled and assessed. Finally one of the approaches is suggested as the most applicable one., QC 20131217

The main purpose of this paper is to summarize the findings from simulating two stochastic short-term planning models for a price-taker hydropower producer. The first model is a two-stage stochastic linear programming problem. Profound sensitivity analysis is provided in terms of volatility in spot market prices and water inflow level. The results show that for the short-term hydropower planning problems the effect of considering price uncertainty in the stochastic model is higher compared to considering inflow level uncertainty. The second model is a two- stage stochastic linear programming problem. The model generates optimal bids to spot market considering real-time market price uncertainties. While simultaneously bidding to both markets, the results are not realistic. To make the bidding strategies more flexible and robust different approaches are modeled and assessed. Finally one of the approaches is suggested as the most applicable one., QC 20131217

The main purpose of this paper is to summarize the findings from simulating two stochastic short-term planning models for a price-taker hydropower producer. The first model is a two-stage stochastic linear programming problem. Profound sensitivity analysis is provided in terms of volatility in spot market prices and water inflow level. The results show that for the short-term hydropower planning problems the effect of considering price uncertainty in the stochastic model is higher compared to considering inflow level uncertainty. The second model is a two- stage stochastic linear programming problem. The model generates optimal bids to spot market considering real-time market price uncertainties. While simultaneously bidding to both markets, the results are not realistic. To make the bidding strategies more flexible and robust different approaches are modeled and assessed. Finally one of the approaches is suggested as the most applicable one., QC 20131217

The main purpose of this paper is to summarize the findings from simulating two stochastic short-term planning models for a price-taker hydropower producer. The first model is a two-stage stochastic linear programming problem. Profound sensitivity analysis is provided in terms of volatility in spot market prices and water inflow level. The results show that for the short-term hydropower planning problems the effect of considering price uncertainty in the stochastic model is higher compared to considering inflow level uncertainty. The second model is a two- stage stochastic linear programming problem. The model generates optimal bids to spot market considering real-time market price uncertainties. While simultaneously bidding to both markets, the results are not realistic. To make the bidding strategies more flexible and robust different approaches are modeled and assessed. Finally one of the approaches is suggested as the most applicable one., QC 20131217

The main purpose of this paper is to summarize the findings from simulating two stochastic short-term planning models for a price-taker hydropower producer. The first model is a two-stage stochastic linear programming problem. Profound sensitivity analysis is provided in terms of volatility in spot market prices and water inflow level. The results show that for the short-term hydropower planning problems the effect of considering price uncertainty in the stochastic model is higher compared to considering inflow level uncertainty. The second model is a two- stage stochastic linear programming problem. The model generates optimal bids to spot market considering real-time market price uncertainties. While simultaneously bidding to both markets, the results are not realistic. To make the bidding strategies more flexible and robust different approaches are modeled and assessed. Finally one of the approaches is suggested as the most applicable one., QC 20131217

Depending on market rules, namely congestion management and balancing management, coordination between wind and hydro producers may be mutually beneficial. In this paper we propose a new collaboration scheme and a fair and transparent method, based on the Shapley value, for splitting the extra value caused by a coordinated bidding and operation strategy. We account for uncertainties in wind forecast and energy price evolution. We demonstrate the proposed approaches on a realistic system including congested lines, wind farm and a hydro plant consisting of several reservoir stages., QC 20101203

As the amounts of installed wind power increases in the power system, the required real-time balancing quantities increases because of the unpredictability of wind power production. Real-time balancing power is usually provided through various market solutions and thus, the prices on such markets will be affected by the increase in wind power production. Consequently, there exist a need for planning and simulation tools concerning the increased balancing demand. This paper therefore describes an estimation model for real-time balancing prices in systems where significant levels of wind power will be added. The model is divided into two steps: The first estimating the changes in required real-time balancing quantities, and the second calculating the corresponding price changes., QC 20100804

New R&D collaboration on "Design and Operation of Power Systems with Large Amounts of Wind Power Production" has been formed in IEA Wind. The R&D task will collect and share information on the experience gained and the studies made on power system impacts of wind power, and review methodologies, tools and data used. This paper outlines the power system impacts of wind power, the national studies published and on-going and describes the goals of the international collaboration. There are dozens of studies made and ongoing related to cost of wind integration, however, the results are not easy to compare. An in-depth review of the studies is needed to draw conclusions on the range of integration costs for wind power. State-of-the art review process will seek for reasons behind the wide range of results for costs of wind integration - definitions for wind penetration, reserves and costs; different power system and load characteristics and operational rules; underlying assumptions on variability of wind etc., QC 20141106

QC 20140811