الفهرس | Only 14 pages are availabe for public view |
Abstract Egypt, as a one of the world emerging economies, pays a lot of interest for securing its future needs of electrical energy according to the international standards at least possible costs. One of the main pillars to achieve this target is through the diversification of the electricity generation mix to include further types of conventional and non-conventional generation technologies. Among the non-conventional technologies, VRES from wind and solar power occupy a considerable area in Egypt’ long term strategy especially knowing that, the country is endowed with huge potential of these renewable energy resources. For this regard, Egypt has already set ambitious plans to expand the contribution of these resources in its future electricity generation mix. Compared to the other types of generation technologies, VRES are characterized by intermittent nature that introduces a number of operational constraints for the power system. The impact of these constraints on the healthy technical and economic operation of the power system magnifies with increasing the share of these intermittent technologies. This thesis will thus focus on developing a new GEP methodology capable of considering the intermittent nature of variable RES in the planning process so that, the resulting optimized energy mix is capable of utilizing the economic and environmental benefits from these RES without compromising the reliability or economics of generating electricity. For achieving this goal, the thesis studies a number of issues related to the main subject of the thesis starting with studying and evaluating the impacts of VRES’ intermittency on the technical and economic operation of the power system especially from the supply demand balance point of view. Then, the thesis reviews the concept of VRES’ capacity credit and the different methods for calculating it. The thesis then studies the different ways for assessing system operational reserves necessary to protect the generation system against the different sources of uncertainties including those arising from VRES. The concept of generation mix flexibility was then discussed and the corresponding impact of this flexibility on the integration of VRES was evaluated. Finally, the thesis develops a new GEP methodology considering the previously discussed issues with the objective of finding the least cost optimized energy mix capable of achieving the long term VRES expansion targets while not violating the economic or reliability behavior of the system. For each of the studied topics, the necessary computer models have been built using the MATLAB software and a number of case studies based on the data available for the Egyptian power system were considered. Accordingly, a set of results have been obtained in terms of VRES and finally the optimum mix of new capacities required to integrate VRES under the different VRES expansion scenarios. The previous results showed that, the intermittency of VRES can introduce severe impacts on the system net load curve that is met by conventional generation capacities. Such impacts include the reduction of the system minimum load level as well as increasing the variability (given by the magnitude and frequency of ramps) in the system net load. Such impacts will require the generation system to be equipped with additional operating reserves as well as calling for additional flexibility in the generation side to cope with the system net load curve. On the other hand, the thesis assesses finds out that, VRES especially wind power can contribute in meeting the system peak loads and not only working as energy sources as have always been considered. In this regard, the contribution of wind power in meeting the system peak loads was found to be in the range of 26.5% to 30.2% of the total installed wind capacity while solar PV power (without storage) was found to have zero capacity credit due to the uncorrelation of solar PV generation with the system peak loads that occur in the night for the case of the Egyptian power system. Finally, in terms of the future energy mix required to integrate VRES into the power system, the study found that, modeling the intermittency of VRES as well as the dynamic limits defining the flexibility of conventional generation capacities in the planning model has shown that, increasing the share of VRES in the power system will require the energy mix to move from depending on cheap base load generation technologies into more flexible types of generation units. This movement however will cause the total system cost to increase and accordingly increasing the cost of the electricity generated by the system driven by the higher generation costs of medium and high flexibility units compared to that of the low flexibility ones. This result thus shows that, the system will pay additional integration costs to achieve the VRES targets in the future and most importantly highlights the need for developing new GEP models and methodologies to simulate with the intermittency of VRES in the planning process. |