Heat Pump Capacity Selection for TPPs with Various Efficiency Levels

Abstract

The variety of possible solutions for the integration of heat pumps (HP) into the circuits of generation facilities dictates the need for preliminary selection of the most promising options. Determining the maximally economically efficient HP capacity may be the key limiting factor for the potential range of solutions. The purpose of the study is to analyze the influence of the type of power equipment of a thermal power plant (TPP) on the choice of HP capacity. In the course of the study, we identified factors that can influence the choice of HP capacity. The correlation between the limitation of the maximum capacity of HP (from the point of view of break-even operation in the electricity market) from the electric capacity and the efficiency of the TPP equipment was established. The ranges of HP capacity for the most common types of TPP power equipment in the Russian Federation were determined. The maximum HP capacity for TPPs based on a steam turbine unit (STU) of type K-300-170- 1P was determined. The method proposed in the paper allows limiting the number of circuits options, as well as TPPs and external conditions suitable for the use of HP. Firstly, under the conditions of a given power system and fuel prices, it is possible to determine the type of power equipment of a TPP in combination with which HP can be used. Secondly, under the conditions of a given power system and type of equipment, the maximum fuel price at which HP can be used at thermal power plants can be determined. Thirdly, under the conditions of a given type of equipment and fuel price, it is possible to select an energy system (region) in which it is possible to build a TPP with HP. It was found that increasing the efficiency of thermal power plant equipment contributes to increasing the HP power capacity and expanding the range of external conditions under which the use of HP becomes rational. It was verified that for TPP equipment of a given type, the use of HP is more rational when operating in cogeneration mode. It was found that, all other conditions being equal, an essential factor determining the range of HP capacity is the electric capacity of TPPs.