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This study presents the evaluation of the performance and acceptability of thermal comfort by students in the classrooms of a university building with minisplit-type air-conditioning systems, in a tropical climate. To carry out the study, temperature and humidity measurements were recorded, both outside and inside the selected classrooms, while the students were asked to complete thermal surveys on site. The survey model is based on the template proposed by Fanger and it was applied to a total number of 584 students. In each classroom, the Predicted Mean Vote (PMV) and the Predicted Percentage Dissatisfied (PPD) were estimated according to Fanger’s methodology, as well as the Thermal Sensation Vote (TSV) and the Actual Percentage Dissatisfied (APD), which were obtained from the measurements and the surveys. The results of this study showed that the PMV values, although they may vary with the insulation of the clothing, do not affect the TSV. Furthermore, comparing PMV vs. TSV scores, a 2 °C to 3 °C difference in operating temperature was found, whereby the thermal sensitivity for TSV was colder, so it could be assumed that the PMV model overestimates the thermal sensitivity of students in low-temperature conditions. In addition, an acceptability by 90% with thermal preferences between 23 °C and 24 °C were also found. These results indicate that it is possible to increase the temperature set point in minisplit-type air-conditioning system from 4 °C to 7 °C with respect to the currently set temperatures, without affecting the acceptability of the thermal environment to the students in the building.

En el presente trabajo se diseña y aplica un procedimiento de planificación energética, compatible con la norma ISO 50001, a una lavandería industrial. Se analizan tres variables de entrada: nivel de producción, estado técnico del sistema y régimen de operación. Se examina el pasado, presente y futuro del consumo del fuel oíl en el sistema de generación y uso del vapor, estableciendo las causas del deterioro del indicador de consumo. A través de un estudio de carga y capacidad en el sistema se identificaron las potencialidades de ahorro mejorando el esquema de operación. Se propuso un nuevo esquema para la operación de las calderas el cual fue implementado lográndose un ahorro del 16% de combustible. Con los resultados de las mediciones se elabora la línea base y se establecen nuevas metas.Palabras clave: Ahorro de combustible, indicador de consumo, ISO 50001, planificación energética, calderas.

This paper discusses energy management in the formation process of lead acid batteries. Battery production and electricity consumption in during battery formation in a battery plant was analyzed over a 4 year period. The main parameters affecting the energy performance of battery production were identified and different actions to improve it were proposed. Furthermore, an Energy Performance Indicator (EnPI), based on the electricity consumption of battery formation (a difficult and rather expensive parameter to measure), is introduced to assess its energy efficiency. Therefore, a Soft Sensor to measure the electricity consumption in real-time (based on the voltage and current measured during battery formation), and to calculate the EnPI is developed. Moreover, Energy Management (EM), aided by the use of energy baselines and control charts is implemented to assess the energy performance of battery formation, allowing the implementation of rapid corrective actions toward higher efficiency standards. This resulted on the average in a 4.3% reduction of the electricity consumption in battery formation.

The objective of this work is to evaluate the perception of thermal comfort that students have in building 10 of the Universidad de la Costa located in the city of Barranquilla. For the investigation the methods for the thermal comfort evaluation are analyzed, selecting the Steady-State methodology of Fanger according to the ASHRAE 55 Standard. With the application of the surveys, the thermal sensation that the students had in the building was evaluated, which was preferably fresh and thermal acceptability where 87% responded satisfactorily to indoor climate conditions in classrooms. It was also obtained that the perception of inner thermal comfort is between 21.1 ° C and 23 ° C of temperature. With the results obtained, recommendations are issued to ensure that students feel thermal comfort and the proper regulation of air conditioning systems.