Competitiveness of power systems with nuclear power plants and with high participation of intermittent renewable energy sources

In the paper are presented and discussed the results of a more complex research of technology portfolio's competitiveness in power systems with high penetration of intermittent renewable energy sources (i-RES). Possible technology portfolios compositions are analyzed. The portfolios comprise very high participation of i-RES, as well as a certain participation of energy storage technologies, but also and other energy technologies like nuclear and fossil fueled power plants. Within the research are developed new competitiveness indicators i.e., dispatchability indicator and the technology portfolio’s assured capacity. The latter is defined on the basis of recently published Ulrich’s and Schiffer’s paper. Obtained results point out that inclusion of pumped-hydro storage plants improves portfolio’s dispatchability. However, within the researched interval up to PHS installed capacities relative to i-RES capacities of 0.3. Numerical values of the dispatchability indicators are still below their values for the portfolio without i-RES. Increased participation of nuclear power plants contribute to the improvement of numerical values of the dispatchability indicators. The sensitivity analysis for the case of two times smaller cost of pumped hydro storage capacities is also performed. Hypothetical change of power system’s technology structure in sense of substitution hard coal and lignite fired power plants with wind generators or with nuclear power plants is also analyzed. The analysis points out that the substitution with nuclear power plants enables much better results regarding power system’s ability to change the power on demand than substitution with wind generators, particularly in the countries with high participation of hard coal and/or lignite in electricity generation