Análise de viabilidade para redução de gastos com energia elétrica: um estudo envolvendo multas por baixo fator de potência e ultrapassagem de demanda em uma base de combustíveis

Abstract

The economic development of a country is directly related to energy demand. In Brazil, in recent years, there has been a shift in the electric load matrix due to the need to meet large-scale demands for sectors such as industry, which represented 36.2% of electricity consumption in 2022. Despite the improvements made, industries still face challenges regarding the efficiency of electricity utilization in their systems, which is measured by power factor, affected by reactive power. Reactive power does not perform useful work and can cause imbalance in the electric load, resulting in a low power factor and fines for consumer companies. In this context, the present study aims to analyze electricity bills to reduce expenses arising from fines for low power factor and demand exceedance at a Fuel Base in Senador Canedo - GO. To do this, data from 2019 to 2022 were collected. The research stages involved surveying active and reactive energy consumption, calculating the power factor, presenting expenses related to low power factor and demand exceedance, suggesting new contractual demands, and analyzing the financial feasibility of installing a capacitor bank. With the results obtained, it was observed that the suggested change in the demand contract could result in savings of R$3,588.89 over eight months. Furthermore, the installation of a capacitor bank is viable for power factor correction. Analyzing a 12-month cash flow, an Internal Rate of Return (IRR) of 9.26% per month was obtained, representing 9.22 times the Minimum Acceptable Rate (MAR) of 1.005%. The Net Present Value (NPV) resulted in R$7,403.49, and the Discounted Payback showed that the return on investment takes 7 months and 17 days. Therefore, it is concluded that it is essential to annually review the contracted demand and change it when necessary to reduce expenses related to exceedance fines and promote the efficient use of energy resources. Additionally, to contribute to financial resource savings, it was found that the installation of a capacitor bank to correct the power factor is a viable and advantageous choice with a rapid return on investment.