Mixed integer linear programming dispatch model for power system of Ukraine with large share of baseload nuclear and variable renewables

Abstract

Ukraine Power Sector is facing the dramatic challenge - a necessity to essentially change its generating capacity structure caused by such main factors: the rapid implementation of intermittent renewables, mainly wind and solar; a high share of obsolete coal-fired thermal power plants, which are not suitable to provide flexibility to the power system; seasonally dependent and very limited water resources for hydro power stations which could provide constrained flexibility and also a high share of baseload nuclear in a generation mix. Another challenge is a high share of a total country's greenhouse gas emissions (about 68% of total Ukraine's GHG emissions) and a huge volume of hazardous air pollutions produced by thermal plants. These factors require a total redesign of current generating capacities to increase system flexibility to meet high renewables implementation volumes while decreasing GHG emissions and hazard pollutions. The easiest option is to implement flexible natural gas generation instead of inflexible coal-fired and nuclear generation, but due to a historically difficult situation with a natural gas supply, this option could potentially cause a negative influence on the country's energy security. We also should take into account an essential amount of investments required to implement a new generation and because of all these factors, the safest way could be keeping baseload nuclear generation, gradually decommissioning coal-fired generation and implementing technologies which are improving flexibility of the Power System, such as electric energy storages. To assess the amount of required installed capacity of electric energy storage in the Ukrainian Power System according to the scenarios of wind and solar implementation the mixed-integer linear programming mathematical model is proposed. The results of simulations show that there are options to keep the current level installed capacity of baseload nuclear generation with essentially high amounts of renewables' installed capacity.