Multi-criterial choice of capacity of power plants based on renewable energy sources and local fuels within local energy system

The purpose of the paper is to develop a methodology for multi-criteria selection of the capacity of a group of power plants included in the local power system which use local energy resources and renewable energy sources. To form alternative options for the structure of generating capacities, an approach is proposed. It suggests setting of a number of power levels of the base-load generating plant and power plants using renewable energy sources with subsequent determination of the capacity of the flexing generating plant to cover the remaining part of the load schedule. For multi - criteria comparison of the alternative options of the generating capacity structure, the TOPSIS method is used, which is modified to take into account the uncertainty of the decision-maker's preferences (the modification of the method consists in using fuzzy value functions at the stage of normalizing estimates by criteria). The application of this method is considered on the example of the Okhotsk district of the Khabarovsk territory. The estimated capacity of prospective consumers is 69 MW. Alternative options of the power generation structures include four types of power plants: local coal -fired thermal, solar, wind, and diesel. The multi-criteria comparison of generating capacity structure options is performed using the following criteria: normalized cost of electrical energy, estimation of environmental efficiency, and assessment of public opinion on the consequences of power plant construction. Some of the most promising options for the structure of generating capacities are presented, depending on the values of the weight coefficients of the criteria. If the criterion has the large weight reflecting economic efficiency, the structure with the predominance of thermal power plant energy generation is the best. If the criteria of environmental efficiency and public opinion feature large weight, the best structure is the one with significant generation from a renewable energy source (solar power plant). The coefficients of using the installed capacity of different types of power stations with different structures of generating capacities are determined. It is shown that the proposed methodology provides the obtaining of the options of the generating capacity structure that correspond to expressed preferences, taking into account the uncertainty of the initial information and development scenarios. Promising options for the structure of generating capacities are selected for more detailed further research.