Theoretical and Experimental Methodology for Studying the Reduction of Evaporation in Open Mining Plant Reservoirs Using a Floating Photovoltaic System

Photovoltaic modules on floats in reservoirs, forming a floating photovoltaic (FPV) system, are proving to be relevant solutions for reducing evaporation and generating electricity. This paper presents a theoretical and experimental methodology to evaluate the reduction of evaporation rates using FPV, applied at Hydro Paragominas' bauxite mine in Pará, Brazil, in a location with a humid equatorial climate. Two test reservoirs were constructed, with and without FPV coverage. The results obtained from models for estimating the evaporation rate based on measurements of meteorological parameters at the site and a reference climate file for the location, indicate a reduction of around 49% in water evaporation with the partial covering of the test reservoir by FPV. An extrapolation to a water surface area of 450,000 m², corresponding to the basins present in the mining company, shows an additional 43,600.5 m³ of water conserved in the month of highest evaporation and 465,961.5 m³ annually, increasing recirculation by approximately 2.9%. This enhances water savings and reduces new water intake, contributing to environmental conservation.