Economic analysis and optimization of household solar heating technologies and systems

Abstract To find an optimal economic solution for single-family solar heating systems, an evaluation model based on the levelized cost of heat (LCoH) is developed. The initial investment and operating costs of typical single-family solar heating systems are determined using case collection and literature study. These data are used to validate the evaluation model. A Python program is developed and used to calculate the LCoH of differently designed solar heating systems. Based on these calculations, the dependence of LCoH on the solar collector area under different heating load intensities, heating terminal units and heated areas are investigated. The optimal solar collector area and the solar fraction are determined for combinations of solar thermal (ST) with four different types of auxiliary heat source was discussed. The results show that LCoH does not necessarily decrease in a solar-assisted household heating system with an increase of solar fraction (SF) compared to a single conventional heat source system. The findings of this study are useful for designers, professionals and government officials to economically optimize the solar heating system for single-family houses.