Industrial decarbonization by a new energy baseline methodology. Case study

The main target of climate change policies in the majority of industrialized countries is to reduce energy consumption in their facilities, which would reduce the carbon emissions that are generated. Through this idea, energy management plans are developed, energy reduction targets are established, and energy-efficient technologies are applied to achieve high energy savings, which are environmentally compatible. In order to evaluate the impact of their operations and investments, companies promote measures of performance in their energy management plans. An integral part of measuring energy performance is the establishment of energy baselines applicable to the complete facility that provide a basis for evaluating energy efficiency improvements and incorporating energy performance indicators. The implementation of energy management systems in accordance with the requirements of ISO Standard 50001 is a contribution to the aim and strategies for improving cleaner production in industries. This involves an option for the industry to establish energy benchmarks to evaluate performance, predict energy consumption, and align production with the lowest possible consumption of primary and secondary forms of energy. Ultimately, this goal should lead to the manufacturing of cleaner products that are environmentally friendly, energy efficient, and are in accordance with the global environmental targets of cleaner manufacturing. This paper discusses an alternative for establishing energy baselines for the industrial sector in which several products are produced from a single raw material, and we determined the energy consumption of each product and its impact on the overall efficiency of the industry at the same time. The method is applied to the plastic injection process and the result is an energy baseline (EBL) in accordance with the requirements of ISO 50001, which serves as a reference for determining energy savings. The EBL facilitates a reduction in energy consumption and greenhouse gas emissions in sectors such as plastics, a sector which accounts for 15% of Colombia’s manufacturing GD

Global air conditioning performance indicator (ACPI) for buildings, in tropical climate

The selection of the most suitable HVAC technology for buildings, is a complex challenge. Many factors such as, the features of the building, climatic conditions, energy consumption, Indoor Air Quality (IAQ), thermal comfort, regulations, aspects, economic and environmental aspects, all of which are shown on a local and national scope. There is no standard methodology that guarantees a single criterion for the selection of HVAC systems. Therefore, in its solution, as in almost all decision-making problems in the field of engineering, two different aspects are considered, theoretical and practical (Moreno, 2002) [1], thus forming a typical multi-criteria decision problem. This study proposes an integral performance indicator for the selection of air conditioning systems (ACPI), based on the multicriteria method of the Analytic Hierarchy Process (AHP), in order to choose the best HVAC system variant, based on its classification by integrating energy, environmental, and economic criteria. For the definition of the criteria, studies on HVAC system selection were reviewed and classified, applying multi-criteria on methods. The criteria were weighted based on surveys issued by a team made up of Professors/Researchers, architects, engineers, installers and managers linked to the HVAC sector. The ACPI model obtained, shows that the highest weighting corresponds to building energy consumption index 26.6%, IAQ 20.6%, thermal comfort 18.6%, CO2 emissions 12.1%, and finally, investment costs, operation and maintenance costs 11.6% and 10.3% respectively. The proposed ACPI, together with its analysis methodology, will allow researchers, architects, engineers, and government administration, to consider a wide range of alternative HVAC systems applied in buildings. With this, it will be possible to select them based on a decision-making model with a reliable source of information

Energy evaluation and energy savings analysis with the 2 selection of AC systems in an educational building

This paper presents an energy performance assessment on an educational building in Barranquilla, Colombia. The electricity consumption performance was assessed using the software DesignBuilder for two different Air Conditioning (AC) systems. The current electricity intensity is 215.3 kWh/m2 -year and centralized AC systems with individual fan coils and a water chiller share 66% of the total consumption and lighting at 16%. The simulation of the AC technology change to Variable Refrigerant Flow (VRF) resulted in an improvement of 38% in AC energy intensity with 88 kWh/m2 -year and significant savings in electricity consumption and life-cycle cost of AC systems in buildings.Este artículo presenta una evaluación del desempeño energético en un edificio educativo en Barranquilla, Colombia. El rendimiento del consumo de electricidad se evaluó mediante el software DesignBuilder para dos sistemas de aire acondicionado (AC) diferentes. La intensidad actual de la electricidad es 215,3 kWh / m2-año y sistemas de aire acondicionado centralizados con fan coils individuales y un enfriador de agua compartido 66% del consumo total e iluminación al 16%. La simulación de la tecnología AC cambia a El flujo de refrigerante variable (VRF) resultó en una mejora del 38% en la intensidad de energía de CA con 88 kWh / m2 al año y ahorros significativos en el consumo de electricidad y el costo del ciclo de vida de los sistemas de CA en edificios

Energy Management by Dynamic Monitoring of a Building of the University of Valladolid

Producción CientíficaThe continuous increase of energy consumption in buildings enhances the importance of implementing energy management systems within the building facilities. These tools allow us to know precisely both energy consumption and use within the building. Monitoring energy consumption provides a clear view not only of the amount, but also of where and when energy is consumed in the building. Besides, a rear analysis of this information allows us to deduce whether there exists an inappropriate consumption, and thus the possibilities of improving building efficiency. A monitoring tool has been implemented within an academic building at the University of Valladolid, applying technological resources of Information Technology and Communication through dynamic monitoring of electrical and thermal parameters. Results obtained are gathered and analysed to directly contribute to improve the use of energy, reduce costs associated with its generation and use, and improve the thermal comfort of the building occupants. Keywords: Dynamic monitoring, energy performances, energy management, reduction of building consumption

modelling the long-term effect of climate change on a zero energy and carbon dioxide building through energy efficiency and renewables.

Producción CientíficaOver the last few years, studies have predicted an increase in the overall air temperature due to climate change. Today’s society is already sensing this change, which could have a negative impact on the envi- ronment and effort s are being made to seek all possible measures to curb it. One of the consequences of this temperature rise would be its effect on indoor comfort within buildings, which may cause higher energy consumption and operational costs, while reducing the useful lifetime of air-conditioning equip- ment. In this paper, an existing zero energy building (ZEB) is being studied to understand the possible effects of climate change on its zero energy status. The building is also a zero carbon building because all of its generated energies come from renewable sources (biomass, geothermal and solar photovoltaic systems). The building LUCIA has the highest innovative technologies in energy systems, design and con- struction elements and is currently considered as one of the top three buildings with the highest LEED certification in the world. According to current European regulations, buildings will tend to become self- sufficient in terms of energy after 2020, and therefore this study will help us to understand the changes in energy consumption within a long-term timeframe, for such zero-energy buildings. With the aid of the Design Builder version 5 software and its EnergyPlus building energy engine, a building model is simu- lated and energy consumption is analyzed for the years 2020, 2050 and 2080 timeframe. The climatic conditions pertain to the city of Valladolid, Spain, which has a continental climate, while the expected changes in climatic conditions have been produced through the methodology developed by the University of Southampton, called CCworldweathergen. Results have shown that the cooling demand would significantly increase for the years 2050 and 2080, while space heating would drop. This will increase the overall demand for burning more biofu- els to cover the added demand in absorption cooling systems. Moreover, the previously excess generated electricity of the building by photovoltaics would then be totally consumed within the building due to increased demand. This implies that the installed systems will operate for longer hours, which will in- crease maintenance and replacement costs. As a result of this study, it becomes possible to quantify the expected changes in energy consumption and prepare preventive actions to anticipate this change, while improving the management and control of both the energy systems and the building

Experimental characterisation of an indirect evaporative cooling prototype in two operating modes

Producción CientíficaThe present paper aims to describe the experimental study developed to characterize an indirect evaporative cooling system made of polycarbonate, designed and manufactured by the Thermal Engineering Group of the University of Valladolid; as well as to introduce the main results obtained. The prototype is characterized by a total heat exchange area of 6 m2 and is installed in a heat recovery cycle in the experimental setup constructed in the laboratory. This setup mainly consists of: an AHU that enables the reproduction of the different climatic conditions to be tested; a climatic chamber where comfort conditions are to be achieved; a circuit to supply water during one of the operating modes; and the due ducts and measurement probes to properly connect the whole system and register the evolution of the interesting parameters. Two operating modes are performed. In the first one, exhaust air from the climate chamber, in comfort conditions, goes through one side of the heat exchanger, producing heat transfer from the outdoor air stream through the plastic walls of the system. In the second case, an evaporative cooling mode is implemented by supplying water to the exhaust airstream. Results obtained show that heat transfer through the heat exchanger polycarbonate wall improves in the evaporative cooling mode. Furthermore, both cooling capacity and thermal effectiveness of the system also increase in the second case. Moreover, global heat transfer coefficient and cooling capacity are improved by higher outdoor air volume flow rates. Finally, higher outdoor air temperatures imply better cooling capacities and thermal effectiveness.This work forms part of the research being carried out within the framework of the “Reduction of energy consumption and carbon dioxide emission in buildings combining evaporative cooling, free cooling and energy recovery in all-air systems”, project supported by the Ministry of Science and Technology through the call for scientific research and technological development research projects. Reference number ENE2008-02274/CON. Ana Tejero wants to thank the Consejería de Educación of the Junta de Castilla y León for the support provided through the Regional Strategy of Scientific Research and Technological Development of the European Social Fund

Sustainable savings applied to operating room ventilation at hospitals located in different climatic zones, through control and regulation strategies

Producción CientíficaIn hospitals, operating rooms are energy-intensive spaces, due to the high flow of outside air required to achieve the necessary indoor air quality. Operating rooms demand ventilation continuously, despite periods of low daily surgical activity. However, by controlling ventilation during inactive periods in the operating room, significant energy savings can be achieved, avoiding penalties on IAQ levels. This paper evaluates the energy savings achieved by introducing ventilation flow control and regulation systems in operating rooms of hospitals located in different climatic zones within Spain. In addition, emissions and economic savings have also been evaluated. Two control and regulation strategies of the air flow to be supplied and extracted in the operating rooms, during periods of inactivity, are studied and include regulation by schedule and regulation by occupancy. Data from a 900-bed university hospital center are used as a reference to evaluate the average occupancy of the operating rooms, and the energy consumption, thus validating the model for calculating the demand of a typical operating room. The energy savings for the regulation by occupancy are 37.5%, and the regulation by schedule are 40% of the annual demand, with respect to an operating room working permanently

Experimental Study and Analysis of Thermal Comfort in a University Campus Building in Tropical Climate

Producción CientíficaThis 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

Energy Consumption Reduction of a Chiller Plant by Adding Evaporative Pads to Decrease Condensation Temperature

Producción CientíficaThe high energy consumption of cooling systems justifies the need for strategies to increase the efficiency of the facilities, in order to reduce the related CO2 emissions. This study aims to improve the performance and reduce the energy consumption of an 8.6 MW air cooled chiller. This installed capacity is biased due to the screw compressors, of 2.98 Energy Efficiency Ratio (EER) at full load (characteristics provided by the manufacturer). The chiller unit has been modified by placing evaporating cooling pads before the condensing coils. The chiller has been monitored for three months, recording over 544,322 measurements (5 min-step data), with and without the evaporative cooling pads, to assess the performance. Data comparison has been done by selecting two days (with and without evaporative panels) with the same health care load and temperatures. Implementing the proposed strategy yields an improvement in the European Seasonal Energy Efficiency Ratio (ESEER) from 3.69 to 4.83, while the Total Equivalent Warming Impact (TEWI) decreases about 1000 tCO2. Energy savings of up to 32.6 MWh result into a payback period lower than 2 years.Junta de Castilla y León (project VA272P18

Experimental study and analysis of thermal comfort in a university campus building in tropical climate

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