Food and Agriculture Organization (FAO) estimates an average of 140, 300, and 589 kWh of electrical energy consumed to process fishmeal, fish, and shrimp, respectively, without adding the costs associated with freezing the finished product. Current research focuses on implementing an Energy Management System (EnMS) in a seafood processing plant that supports energy savings at low cost. This article presents, as a contribution from the qualitative point of view, the non-need for external financing to implement the EnMS under the ISO 50001 standard and the identification of the Energy Performance Indicators (EnPIs) of the case study plant. The energy awareness of the workers is evident when analyzing the results of the surveys carried out before and after the implementation of the EnMS. As part of the research, an Automated Reporting System (ARS) is developed; the performance enables energy information to be concentrated in a single file under a standard format approved by the energy commission and sent systematically. From a quantitative point of view, there is a 13.2% reduction in the total electricity consumption of the plant and a decrease in the cost of electricity needed per ton produced, from 9.40 USD to 7.30 USD. The emission of greenhouse gases into the atmosphere due to electricity consumption decreases by 13.78%.