The use of electricity to heat bath water is still quite common in Brazil, especially in the South and Southeast regions. This practice represents about 24% of the total energy consumption in the residential sector. Additionally, its usage is concentrated between 6 and 9 PM, leading to serious issues in energy generation and distribution during this interval. Given the importance of rationalizing the electricity consumption, the aim of this paper was to conduct a technical-economic analysis for the implementation of a hybrid solar heating system to supply the demand for hot water in the bathrooms of a poultry slaughterhouse located in the Western region of Paraná. For this, different scenarios of usage were developed, where the type of solar collector and the auxiliary power source were varied and a comparison between the alternatives and the conventional water heating systems was made. A calculation routine based on the F-Chart method was used to size the alternative systems. The Net Present Value (NPV), the Internal Rate of Return (IRR) and the discounted Payback were used as decision-making criteria. All configurations sized in this study were proved to be viable. However, the most interesting one, from a technical-economic point of view, was the combination of the flat-plate solar collectors and the electric auxiliary power source. The comparison of this scenario with the conventional source showed an NPV of R$ 92,916.84, an IRR of 59.9%, and a payback period of 1 year and 11 months.