The actual problem of modern energy, both in Ukraine and around the world, is the transition to energy-saving technologies, such as heat pumps using renewable energy sources. The purpose of this study is to develop a techno-economic method for the rational choice of air source heat pumps offered on the market for use in bivalent heating systems, taking into account the technical characteristics specified by the manufacturers and local climatic and economic conditions. The scientific novelty is the optimization of the objective function of resulting costs according to energy, climatic and economic parameters for the subsequent choosing of the most rational heat pump from the model range. The practical value of this study lies in the development of a software package that makes it possible to obtain an unambiguous analytical solution for choosing the most rational heat pump option from a model range based on the data given in the manufacturer's catalogs and climate tables for a specific region, without carrying out labor-intensive traditional technical and economic calculations. Using this method, a rational model of a heat pump was chosen for the bivalent heating system of a building in Kharkiv. The result of the calculation is the construction of a graph of the objective function of the resulting costs for the analyzed number of heating seasons and the accepted electricity tariff. The rational model of the heat pump corresponds to the minimum of the resulting costs.