Estudo de caso da reestruturação do sistema de água gelada com termoacumulação sob a visão da eficiência energética

Abstract

This paper presented a case study on the restructuring of the chilled water system at the Lactalis do Brazil plant, located in Carambeí - PR, with a focus on energy efficiency. The industrial sector accounts for approximately 35% of national electricity consumption, with refrigeration responsible for up to 40% of the demand in dairy plants, which reinforced the relevance of the subject. The intervention consisted of removing seven dedicated repressurization pumps, with a total power of 100 HP, and adopting a thermal storage system with centralized pumping, aiming to reduce losses caused by oversizing and mechanical seal leakage. The methodology applied was a practical case study, with a comparative analysis between the previous and the current system, based on real data on energy consumption, operating costs, and performance indicators. After implementation, a reduction of approximately 67.6% in the energy consumption of the repressurization pumps in the analyzed sector was verified, decreasing from 444,709.44 kWh to 143,856 kWh per year, which represented significant savings in operating costs and the elimination of preventive maintenance expenses. This reduction contributed to the mitigation of around 12.85 tons of CO₂ per year, reinforcing the environmental benefits of the intervention. The total investment for implementing the solution was R$ 4,805,982.05, with a payback time of 9.78 years, equivalent to approximately 24% of the system's projected lifespan, ensuring economic feasibility and positive cash flow for more than three decades. In addition to direct savings, the simplification of the hydraulic circuit improved the load factor and reduced continuous demand, increasing the electrical stability of the plant. It was concluded that integrating thermal storage systems into industrial refrigeration is a technically viable, economically attractive, and environmentally responsible strategy, aligned with energy management practices and national efficiency goals. The results obtained demonstrated that well-planned structural interventions can generate expressive gains in sustainability and competitiveness for the dairy sector, consolidating the importance of adopting technologies that promote consumption reduction and environmental impact mitigation.