Daniel Waniek

Influences of wind energy on the operation of transmission systems

In this work the impact of wind energy on the power flow is analyzed. After the development of a reduced sample network, possible network congestions are identified and the costs for the required redispatch of the generation are evaluated. To avoid or reduce the probability of congestions, different network upgrades can be installed. The efficiency of additional lines and power flow controlling devices is discussed on the basis of power flow calculations and dynamic simulations.

Flow-based evaluation of congestions in the electric power transmission system

In this paper the practical implementation of a flow-based method for the allocation of limited cross-border transmission capacity is modeled. In order to evaluate the efficiency of the approach compared to traditional methods based on bilateral conventions for the trading transactions, economic and technical performance indicators are presented. The developed approach is applied to a model of the Central Western European region. The results show that the flow-based method can improve the network efficiency leading to lower generation cost and higher economic welfare in the regarded region. The necessary simplifications of the load flow equations cause inevitable deviations of the estimated flows but the general behavior is uncritical. Apart from that, single situations require a sensitive monitoring by the involved parties.

Analysis of market coupling based on a combined network and market model

In this paper the possible implementation and the efficiency of multilateral market coupling are evaluated. Market coupling is known as the cooperation of power exchanges and other market players in order to utilize the limited capacity of a meshed electricity transmission system in an efficient way. Based on a three-part combined network and market model of the Central Western European region, the congestion management is simulated and possible alternatives in the different steps of the practical execution are compared to each other. The results are rated from an economic and technical point of view in terms of system-wide welfare as well as utilization and security of the congested lines.

Estimation of the costs due to renewable energies for a transmission system operator

By nature the generation from renewable energies sources is not performed on demand, but on offer. This yields the need of converting the energy to the actual demand. In Germany the execution of this process is obliged to the four transmission system operators. In this paper the occurring costs of the process of purchasing and transmitting renewable energies in Germany are analyzed for sample control areas. These costs include the expenses for additive required control power as well as the expenses caused by the special balancing group for renewable energies. During the operation of this balancing group accrue costs for balancing energy and as a result of trading transactions at electricity markets. Through this paper, the main question of the sensitivity of these costs from parameters in the observed control area is addressed.

Modeling of the operating reserve market based on the theory of industrial organization

The adequacy of the design of operating reserve markets is essential to realize low tariffs for the customers. Due to the two-stage auctioning, an appropriate model is necessary to analyze the decision problem of the market players. Based on simplified assumptions, the presented concept is transferred to a sample market structure in order to derive the market behavior and the results. The model shows that because of the stochastic call of operating reserves arbitrarily high equilibriums for the energy bids are possible in theory. The market design with independent capacity and energy auctions cannot lead to prices near to the marginal costs.