Investment planning for flexibility sources and transmission lines in the presence of renewable generation

Abstract

Environmental and political factors determine long-term planning for renewable generation around the world. The rapid growth of renewable generation requires timely changes in power systems operation planning, investments in additional supporting flexible assets and additional transmission capacity. The development trends of restructured power systems suggest that the current tools and methodologies used for investment planning are lacking the coordination between transmission and flexibility sources. Moreover, a comprehensive analysis is required for efficient investment decisions in new flexibility sources or transmission assets. However, literature does not provide an efficient modeling tool that will allow such a comprehensive analysis. This dissertation proposes mathematical modeling tools as well as solution methodologies to support efficient and coordinated investment planning in power systems with renewable generation. Proposed mathematical tools and solution methodologies are then used to provide an analysis of transmission investment planning, energy storage investments planning as well as coordinated investment planning. The analysis shows that to achieve socially optimal outcome transmission investments should be regulated. Also, the results of the numerical simulations show that coordinated investment planning of transmission, energy storage and renewable generation will result in much higher investments in renewable generation as well as more efficient operation of renewable generation plants. Consequently, coordinated investment planning with regulated transmission investments results in the highest social welfare outcome. The dissertation is structured as follows. Chapter 1 provides introduction to transmission and energy storage investment planning as well as literature review and list of contributions and publications. In Chapter 2, investment planning in energy storage systems and flexibility sources is discussed. Energy storage systems are considered as the most promising flexibility sources which should be integrated into system in order to facilitate growth of renewable generation. In addition, the chapter compares various sources of flexibility such as flexible thermal generation and hydro power and shows that all these sources of flexibility can be modeled in a unified fashion. In Chapter 3, transmission investment planning is presented. The chapter focuses on incentive-based regulation which can support socially optimal transmission investments. In Chapter 4, comprehensive and detailed mathematical models applied to transmission investment planning are presented. This chapter also includes various reformulation and linearization techniques, as well as novel decomposition algorithms. Finally, Chapter 5 presents a list of main conclusions. In the Appendix of the dissertation, all published and submitted manuscripts are attached in the following order: first, accepted and published manuscripts J1 and J2; second, submitted manuscripts J3 and J4; third, conference paper P1.