Solar water heating for a hospital laundry: A case study

• A technical and financial analysis of a solar water heating system for a laundry is presented.
• The proposed methodology increases Annualized Life Cycle Savings by 8.5%.
• The methodology used reduces the initial cost of the system by about 6.3%.
• The optimization of the system is targeted to the Annualized Life Cycle Savings.

Solar energy has enormous potential in many areas of industrial activity in Brazil, since much of the country has high levels of sustained solar insolation. Unfortunately, there are few industries that use solar energy for water heating even though some industrial processes need water at temperatures that could be easily obtained from flat plate collectors. This paper uses a numerical simulation to study the technical and financial viability of a solar water heating system for a hospital laundry in the city of Recife (8.1°S and 34.9°W). After modeling the system’s components, some parameters of the system were optimized, such as the tilt angle of the collector, water flow rate, area of the collectors, and the size of the water tank. The economic analysis was carried out by comparing the annualized life cycle savings for the solar powered system versus the system currently in use which burns natural gas. The results showed that the reduction in natural gas consumption brought about by using a solar heating system makes it an economically viable option.