Alexander Weber

Efficiency of continuous double auctions in the electricity market

Intra-day electricity markets are considered as important mechanisms to reconcile short-term fluctuations of energy production with consumption. This even gains in significance in systems with heavy intermittent production at virtually no variable costs, such as wind energy. In Europe, intra-day markets are often designed as continuous double auctions where bid and ask orders are collected continuously, ranked by price and time of arrival. Although this market type can be considered as delivering more or less efficient results, the trading process itself is time-consuming. This poses the question whether continuous markets yield comparably good results when flexibility of market participants to change their schedules at short notice is costlier than having changed them earlier. We apply an extended zero-intelligent-trader simulation model to assess the impact of costly flexibility on market outcomes. We find that costly flexibility with a correspondig demand for flexibility may negatively affect the efficiency of continuous double auctions. For the energy market, this could imply that the markets ability to exploit flexibility is systematically limited.

RES-E Integration in Germany using the example of EnBW TSO

In Germany, the four transmission system operators (TSOs) are in charge of integrating the intermittent electricity production from renewable energy sources (RES-E). EnBW Transportnetze AG (EnBW TNG) is responsible for the market integration of about 14 % of the RES-E production in Germany. This paper describes the integration of RES-E at EnBW TNG, the TSO in the southwest of Germany. The basic idea of most of the described processes is common to all German TSOs.

Model-based combustion analysis for the development of control functions at the EiL-test bench

A methodology of model-based combustion analysis for the development of control functions at the test bed is considered. One focus is hereby the usage of semi-physical models, which are obtained by combination of theoretical physical models with experimental models in order to adjust the overall model to the actual, nonlinear behavior. In the context of engine modeling, the physical model structure offers a priori knowledge and physical interpretability. The experimental part ensures model adaption to real engine behavior, which is realized by using online parameter-estimation methods. Furthermore, the combination of both allows the transferability to other engines. The resulting modeling approach is particularly intended for online applications.

Robust transmission planning — An application to the case of Germany in 2050

Technological advances and climate considerations drive substantial changes within the electricity sector. Yet, these changes, although their thrust might be intuitive, are subject to large uncertainties: Technologies may be available earlier or later, international/regional co-ordination may work better or worse etc. This poses significant challenges to the task of transmission planning: Therefore, in this paper, we analyze how these uncertainties may impact transmission planning and how these impacts can be mitigated. We put a special focus on “robust” optimization techniques and analyze a stylized model of Germany in 2050. We find, somewhat counter-intuitively, that “classical” robust optimization techniques may lead to imbalanced decisions, focusing on only one of several possible realizations, especially when the absolute impact of the exogenous uncertainties leads to strongly differing costs. In that case, minimizing the maximum regret may be more preferable. Overall, we find evidence that techniques of robust transmission planning allow for savings in transmission investment and power system operations.

Is There Still a Case for Merchant Interconnectors? Insights from an Analysis of Welfare and Distributional Aspects of Options for Network Expansion in the Baltic Sea Region

Despite the ongoing appetite of financial investors for merchant investments into the European electricity network, the EC is reluctant to approve such undertakings, thus implicitly favoring regulated investments. Based on a two-level model, we analyze the impact of profit-maximizing merchant transmission investment as compared to welfare-maximizing regulated transmission investment. We apply the model to the Baltic Sea region, which has in the past been subject to rapid interconnector development and still would benefit from increased interconnection. We obtain stable results indicating that merchant investment may well contribute to overall welfare, but at the same time, “the merchant takes it all”, i.e. in many cases merchant profits are close to the overall efficiency gain, and sometimes even higher. These results underline that that distributional aspects, besides mere welfare arguments should be taken into account when analyzing the impact of merchant transmission investment.

Merchant and regulated transmission investment: The case of the Baltic Sea region

Considering the current European framework in place, investment into (cross-zonal) electricity network interconnection can be merchant, profit-maximising (i.e. exempted according to Art. 17 of EC 714/2009) or regulated (i.e. rather welfare- than profit-maximising). We propose a framework for analysing the interaction of a profit-maximising merchant line investor and a cost-minimizing, regulated investor. We assume that the merchant line investor makes its decisions first, anticipating the reaction of the cost-minimizing regulator. The model is set up as a mathematical problem with equilibrium constraints. We apply the model to the Baltic Sea region (excluding the allowance for withholding capacity, which is in line with current legislation) and discuss the results. Our results indicate that - seen from a customer payments perspective - allowing for merchant investments is nearly as bad as having no merchant interconnector at all.