Impacts of large quantities of wind energy on the electric power system

Abstract

Wind energy has been surging on a global scale. Significant penetration of wind energy is expected to take place in the power system, bringing new challenges because of the variability and uncertainty of this renewable resource. Therefore, the understanding of how wind energy could affect a power system is of great significance to system operators, regulators, investors and policy makers. This thesis explores both the long-term and the short-term potential impacts of large quantities of wind energy on power systems. Two computer based models and an analytical model are used or developed as the primary tools for this thesis. Among the models, the ReEDS model is used to project the power system capacity expansion for the ERCOT case and the contiguous US case, under different C02 policy scenarios, for the long-term analysis. The Memphis model is used to simulate in high resolution the operation of a well adapted system for both the ERCOT case and the Spanish case, for the short-term analysis. Sensitivity analyses are also performed to investigate the responses of a power system to different penetration levels of wind energy, as well as to operating reserve requirements. Further, the representation at the operation level in ReEDS is assessed by benchmarking with Memphis. It is concluded in the thesis that in the long term, wind energy is less likely to grow without C02 emission restrictions. The power system could experience significant transition to one that is sufficiently reliable to accommodate a strong penetration of wind energy. Sufficient investment in flexible generation capacity will be necessary to back wind energy. In the short term, an increase of wind energy will displace the marginal technology. Different operating reserve requirements also affect the decision of generators between producing and being idle to provide reserves. Therefore, for system security and reliability, adequate regulatory and policy measures should be adopted to orient investment and operation decisions. Last, the benchmarking results show that ReEDS provides fair representations of the power system at the operational level.