PhD Güray Kara: Thesis for the Degree of Philosophiae Doctor
Faculty of Economics and Management, Department of Industrial Economics and Technology Management, NTNU, 2022:31.


In the research for this thesis, operations research techniques are applied in power markets and systems to investigate the usage of flexibility under conditions of uncertainty. Economic dispatch models and optimal power flow models are used for designing and analyzing power markets and systems. In the economic dispatch models, economic factors and their relations with power markets are analyzed, while in optimal power flow models, answers to power grid operations for voltage and network congestion are searched. During the research, the first research question addressed was how to determine the flexibility concept, products, and services about various power and energy markets. This led to the development of a theoretical and empirical taxonomy for flexibility trading and related market structures. The second question addressed during the research considered how to use flexibility according to two separate systemic approaches, different tariff designs to exploit flexibility usage for reducing peak pricing, and a stochastic optimal scheduling methodology for end user’s flexibility assets to solve grid problems. The third and final question addressed during the research concerned how it is possible to have a cost-efficient and productive local flexibility market design for grid operations under uncertainty.

Answers to the research questions are provided in the four papers that form the basis of this thesis. Paper I explains the taxonomy and provides an overview of flexibility and its products along four dimensions—time, spatiality, resource, and risk profile—according to the market design. Paper II shows how to activate and use flexibility with a dynamic tariff design for peak shaving. Paper III provides solutions to grid problems under uncertainty (i.e., voltage and congestion) by using flexibility from the demand side, storage side, and supply side. Lastly, Paper IV proposes a stochastic local flexibility market design, bidding, and dispatch methodology to contribute grid operations on a local scale.

The work was funded by CINELDI, and was a part of the research area Interaction DSO/TSO.

Magnus Korpås

WP3 Lead
+47 970 42 009
Magnus Korpås
WP3 Lead

Overview of the research papers

  1. G. Kara, A. Tomasgard, H. Farahmand: "Characterization of flexible electricity in power and energy markets". This paper was sent to the Renewable & Sustainable Energy Reviews at August 2021. It is currently under review.
  2. S. Backe, G. Kara, A. Tomasgard: "Comparing individual and coordinated demand response with dynamic and static power grid tariffs", Energy, Vol. 201, 2020.
  3. G. Kara, P. Pisciella, A. Tomasgard, H. Farahmand: "The Impact of Uncertainty and Time Structure on Optimal Flexibility Scheduling in Active Distribution Networks", IEEE Access, vol. 9, 2021.
  4. G. Kara, P. Pisciella, A. Tomasgard, H. Farahmand, P. Crespo del Granado: "Stochastic local flexibility market design, bidding, and dispatch for distribution grid operations", Energy, vol. 253, 2022.