RELIABILITY OF POWER SYSTEMS WITH CLIMATE CHANGE EFFECTS ON PV AND WIND POWER GENERATION

Abstract

Concerns over global climate change has led utilities to reduce greenhouse gas (GHG) emissions by decarbonising the power sector. The accelerating rate of climate change is likely to expose a decarbonised power system to climate related stresses. In particular, Photo Voltaic (PV) and wind power generation systems comprise a significant share in the power grid, which is potentially vulnerable to climate change, and therefore may impact the reliability of power systems with their integrations. Typical reliability assessments do not consider the climate effects and related stresses either on the PV or wind power generating systems or at their component levels. Therefore, this thesis investigates and addresses the challenges of reliability assessment of power grid with the interaction of climate changes and renewable power generation systems. As a part of the investigation, the thesis proposes a novel systematic framework to assess the PV system components’ availability with the interaction of future changes in climate. The framework is developed to quantify the climate related stresses on the hierarchical levels of a PV system, which include component, subsystem, PV system and the grid. The framework was formed by considering multiple elements including thermal stress, bathtub curve, ageing and degradation level and operated on Markov chain embedded Monte Carlo simulation. The uniqueness of the framework is its ability to identify the critical components in a PV system that lead to climate-associated failures. Thesis also proposes a comprehensive framework to assess the reliability of a PV and wind power integrated power system accounting climate change impacts by deploying diverse levels of GHG emission scenarios. Uncertainties in the future climate scenarios were established by proposing an advanced stochastic model considering likelihood-based Markov chain method for generating future climate scenario. The proposed model is integrated to the reliability assessment framework to assess realistic impacts on the reliability of a power system. Investigations were suggested the impacts of climate change effects on PV and wind power generation system were true and in quantitative terms PV systems are more vulnerable to climate change effects than wind power generating systems. The climate change related true impacts on PV and wind power generating systems could be mitigated by quantifying change in impacts quantitatively and then systematic replacement of vulnerable sub system components in time before their end of life. Further investigations suggest that IGBTs and capacitors are key components that are more sensitive to thermal stresses of climate change effects resulting a considering impacts on their availability and on the power system reliability with their presence. Further assessments also revealed that the impacts on power system reliability due to the climate change effects on PV and wind power generation system were not uniform over the long run which further emphasises the need of a quantitative and system assessment in order to expose true impacts of climate change on PV and wind power generation system extending to the entire power system reliability. The thesis provides a solid foundation of frameworks required in the quantitative assessment.