Alexis Sagastume

Corporación Universidad de la Costa · Facultad de Ingeniería, Departamento de Energía

This study discusses the introduction of elastic embedment support in the preliminary design of shafts. The preliminary design of shafts idealizes the supports by considering them mobile articulated support, fixed articulated support, or embedded support. In several cases, these idealizations deviate from reality. While articulated supports produce...

The present study aims to assess the vapour bubble absorption into the ammonia/lithium nitrate (NH3/LiNO3) solution by using an optimized CFD model. A detailed methodology to build up the CFD model is presented, as well as its validation using experimental data. The operating conditions set corresponds to an absorption chiller driven by low-tempera...

This study aims to assess the performance of a solar/gas assisted absorption chiller using NH3/LiNO3 for air conditioning in malls at the environmental conditions of the city of Barranquilla, Colombia. The performance of an NH3/LiNO3 absorption chiller with a nominal capacity of 352 kW is assessed using natural gas and solar energy for driving of t...

The need of reducing the dependence of fossil fuels and CO2 emissions have motivated the diversification of energy matrix. Among the Renewables, the hydropower shows better characteristics compared to solar, wind, biomass and geothermal, because its low CO2 emissions, higher density and others technical factors. Within the Hydropower, the Hydrokine...

This study discusses the causal analysis and solution of the teeth failure in sprocket drivers in a clinker scraper conveyor of a cement plant. The failure consisted of the progressive surfacing shape loss of the teeth, progressively deteriorated to the operating conditions of the system, causing dynamic loads, which affected the mechanical transmi...

Increasing access to electricity is essential to improve human development in poor and developing countries. To this end, the relationship between electricity consumption and human development is critical to supporting the process of decision-making. However, the discussion on this topic is limited. In Colombia, developing adequate policies require...

The inequality in electricity consumption (EC) in Colombia is assessed based on the per capita electricity consumption (ECpc) and the Gini coefficient. The ECpc was defined with the total electricity consumption and population for each department and rural and urban areas. Furthermore, the national ECpc was assessed according to the Colombian socio...

Currently, the feasibility to replace standard efficiency electric motors with higher efficiency ones is assessed with considerations differing from real operating conditions in the industry. This study compares the feasibility of replacing 26 standard efficiency motors (IE1) with high-efficiency efficiency ones (IE2 and IE3) in a sugar plant, base...

Modern energy services are essential to replace the extensive use of traditional biomass fuels driving several environmental, health, and social issues affecting the welfare of low-income citizens. Particularly, in Colombia, 11% of the households rely on inefficient firewood cooking systems, while two million people have either intermittent access...

This study discusses the technical, environmental, and economic feasibility of using absorption chillers driven by solar energy and/or natural gas, in selected shopping malls in Barranquilla, Caribbean region of Colombia. The high solar irradiation and the low prices of natural gas in the cities of the Caribbean region of Colombia are attractive co...

Municipal solid remains an issue that needs to be addressed globally towards a more circular economy and lower environmental impacts. In Colombia, over 96% of municipal solid wastes are landfilled, with little recycling or revalorisation of wastes and several environmental implications. With the technological development of different waste-to-energ...

The absorber is a key component of absorption cooling systems, and its further development is essential to reduce the size and costs and facilitate the diffusion of absorption cooling systems. Computational fluid dynamics (CFD) can facilitate the characterization of the equipment used in absorption cooling systems at lower costs and complexity, but...

Improving the thermal efficiency of internal combustion engines is essential to reduce the operating costs and complaints with the increasing environmental requirements. Thermoelectric generators came up as an opportunity to reuse part of the heat loss with the exhausts. This paper evaluates the performance of a thermoelectric generator to improve...

The limited availability of local climatological stations and the limitations to predict the wind speed (WS) accurately are significant barriers to the expansion of wind energy (WE) projects worldwide. A methodology to forecast accurately the WS at the local scale can be used to overcome these barriers. This study proposes a methodology to forecast...

There is a large potential for biomass-based renewable energy production Colombia which mostly remains untapped, accounting for a marginal 0.8% of the electricity production. Moreover, Córdoba is a department with important developments in agriculture and agroindustry, where significant amounts of biomass wastes are generated. In total, these waste...

The wear degree of knives in hammermills strongly influences electricity consumption, productivity, and total operating costs. Currently, the timely replacement of the knives set is decided based on visual inspections, a feedstock load or a lifespan defined, the electric demand of the mill as compared to the limit of the motor driving it, or the vi...

The use of compressed air in industry is an important and yet overlooked energy carrier. Although there are different energy-saving measures discussed in the specialized literature, there is little discussion on the energy performance of the production and use of compressed air. This study developed a new approach to assess the energy performance o...

Cuba currently faces a limited availability of transportation to support the development needs of the country. Transport availability is mostly limited because of fuel shortage. Moreover, Cuba has an important production of sugarcane, with a significant potential to further increase its production. Using sugarcane-based bioethanol is a significant...

In Colombia, agriculture and livestock production, and the processing agroindustry (including slaughterhouses) are a significant source of biomass wastes, which often generate significant environmental impacts. Waste-to-energy technologies, particularly direct combustion and anaerobic digestion systems are an alternative to revalorize these wastes...

The data presented in this article was used to assess and compare the most important methods used to estimate the efficiency during the operation of induction motors at different loads and power supply conditions. The experiment was developed in a test bench including a three-phase induction motor of 1.1 kW (De Lorenzo DL 1021). In addition, an adj...

The data included in this study was calculated based on data provided by the national project registry provided by the Colombian government. The data forecasts the evolution of the power generation capacity registered in non-conventional renewable energy source projects in three scenarios of implementation of the power generation capacity registere...

Power generation with thermoelectric devices in internal combustion engines is an alternative to recover some of the energy loss with the exhausts. This data article supports a study that assesses the potentialities of energy recovery with thermoelectric generators in diesel engines and its influence on gaseous emissions. To this end, a set of expe...

Abstract: The aim of this study is to improve energy performance at a battery factory in Colombia by introducing the energy management approach defined in ISO 50001. In the study, the main energy consumptions were identified in the battery formation, the compressed air system and the large electric motors. An energy review was performed in the fact...

El trabajo trata las metodologías y los indicadores para la evaluación de los impactos de uso del agua dulce, los métodos existentes analizan fundamentalmente la cantidad de agua usada con relación a los impactos ocasionados. Teniendo en cuenta que hay una necesidad reconocida para considerar los impactos, específicamente sobre bases del ciclo de v...

Thermoelectric generation is an alternative to recover some of the wasted energy trough an exhaust of the internal combustion engines. This paper assesses the performance of a thermoelectric generator with 20 modules by implementing a waffle heat exchanger. Experimental results showed a variable range of power recovery from 57.87 W to 71.13 W for B...

Resumen: El objetivo de este estudio es mejorar el rendimiento energético en una fábrica de baterías en Colombia mediante la introducción del enfoque de gestión energética definido en ISO 50001. En el estudio, los principales consumos de energía se identificaron en la formación de la batería, el sistema de aire comprimido y la gran red eléctrica mo...

This study identifies the main factors affecting the electricity efficiency and productivity of the lead acid battery formation process. A representative sample of 12,286 battery formation processes, developed between June 2014 and June 2015, were used in a statistic analysis. As a result, an energy performance indicator was developed to assess the...

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 were 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...

Improving and managing the electricity efficiency in hotel facilities is essential to reduce the hotel operation costs and its environmental impacts. The data presented shows the evolution of the electricity consumption and management between 2013 and 2015 in two hotel facilities in Cuba (one beach hotel and one city hotel). The data additionally i...

Resumen En el trabajo analiza el modelo cubano de desarrollo sostenible y se explican las causas de que sea el único país del mundo que según el World Wide Fund for Nature cumpla con los requisitos para ser sostenible. Se exponen los resultados alcanzados en la educación y la salud que explican los altos resultados del Indice de Desarrollo Humano (...

Different methods have been developed to estimate the energy efficiency of induction motors. The accuracy of these methods vary with the load factor, the unbalanced voltage (UV) and harmonics. The feasibility of these methods for efficiency estimation in real-time were theoretically and experimentally assessed during the operation under different o...

The Government of Cuba proposed in the year 2011 an update of the economic and social model, where the management of energy is an element of influence in the economy of the country. This led to the approval of a policy for the development of renewable sources and the efficient use of energy. Another important aspect is the National Plan for develop...

This study discusses the potentialities and current situation of the electricity generation from non-conventional renewable energy sources (NCRES) in Colombia. In particular, three scenarios considering the increment of NCRES electricity based generation installed capacity are discussed. The three scenarios are compared to the 2020 forecast of the...

Autor a quien debe ser enviada la correspondencia Resumen En este estudio que se presenta se integran técnicas utilizadas para analizar problemas asociados a la climatización que por sí no son suficientes para evaluar todo un sistema de acondicionamiento de aire. Se utiliza la termografía para obtener el perfil de temperatura en el área de incidenc...

This study integrates different techniques to analyze some issues of the air conditioning system of a commercial establishment. A thermographic camera is used to assess the temperature profile in the area covered by the air conditioning system and also to detect the higher temperature spots. The air conditioning system of the facility is simulated...

Electricity stands as the main energy used for lead-acid battery (LAB) manufacturing. This study introduces an energy management methodology to address the electricity consumption in lead-acid battery plants, improving efficiency standards. The “equivalent battery production” is introduced to define the energy performance criteria to be met in the...

Assessing the biomass based electricity potential of developing nations like Cuba can help to reduce the fossil fuels dependency and the greenhouse gas emissions. The data included in this study present the evolution of electricity production and greenhouse gas emissions in Cuba. Additionally, the potentialities to produce biomass based electricity...

The emissions of greenhouse gases stand as a major threat of today. Moving towards CO2 neutral or low-carbon economies is a need to achieve sustainable development. This study assesses the potentialities to move Cuba towards a low-carbon economy by replacing the current electricity mix, dominated by fossil fuel based electricity generation, with bi...

“Cleaner Production“(CP) is about less and more efficient energy and materials use and the substitution of more harmful products (for the environment and health) by less dangerous ones. CP was the reply of the industry to the call for sustainable development as launched by the WCED (1987) and further elaborated in Rio’s Agenda 21 (UN, 1992). During...

By 2013, the province of Cienfuegos in Cuba consumed about 5165 GWh of primary energy, of which an estimated 60 % was used to produce 767 GWh of electricity. 29 % of the primary energy was obtained from renewable fuel, and only less than 5 % of the biomass energy, was used to produce about 27 GWh of biomass based electricity. This study proposes an...

The outcome of Life Cycle Assessment (LCA) studies is strongly influenced by the selection of the functional unit, which must be defined in such a way that, when products are compared, the amounts compared have identical utilities. LCA studies of cements mostly use mass based functional units (MFU). However, since different cements have a different...

In the paper an analysis scheme able to considerate of all the main geometric and load factors that affect the behavior of a hydraulic cylinder in its action as a flexural-compression member. Also, experimental validations of the model are shown too. A methodology to identify the conditions leading to the instability of the cylinder is established.

Universities are key stakeholders in teaching, researching and supporting the implementation of cleaner production activities. This case study discusses the experience of establishing and operating the Cleaner Production Center at the University of Cienfuegos (Cuba).Establishing, starting-up and running the center during its first four years of act...

The outcome of Life Cycle Assessment studies is strongly influenced by the selection of the functional unit, which must be defined in such a way that, when products are compared, the amounts compared are true substitutes of one another. Environmental assessments of Portland cements (PC) and blended cements (BCs) mostly use mass based functional uni...

Hotels are among the most energy intensive tourism facilities. To monitor and control the monthly and yearly energy consumption in hotels, different indicators have been proposed. These indicators, developed on yearly or annual basis, do not permit rapid detection and mitigation of malpractices and overconsumptions in hotel facilities. Moreover, th...

This study introduces a mathematical model to describe the floating effects of the top roll in sugarcane mills. The model is developed from experimental data measured during the operation of a sugarcane mill. The measured data is fitted using the top shaft rotation period of the mill and dividing on intervals to individually fit each interval obtai...

This article determines the water footprint from the potato crop in Cuba between the years 2009 and 2012 using the CROPWAT model. Climate, yields and fertilization data are specific to each of the areas where the crops were grown. The results are compared with previous works in other countries in Latin America and the Caribbean. In the case of Cuba...

As pork is indispensable in the diet of Cuban people, the government was forced to prioritize its production. Pig production causes several environmental impacts related with air, water and soil pollution, which can be quantified with the application of Life Cycle Assessment that allows to optimize products and processes by identifying their enviro...

Producing lime demand high energy consumption and implies high CO2 emissions and other environmental impacts significant. This work aims to establish a methodology for optimizing the calcination of limestone kilns normal vertical Cuba, to consider the influence of the quality of lime on the economic contribution margin. In this case they are used a...

The paper makes a quantitative analysis of the main water consumers processes in the company Cementos Cienfuegos SA, from which actions for savings are proposed through the introduction of reuse, collection and use of rain water. A preliminary assessment of the proposed tasks was made, that led to the conclusion that the company has potential to si...

The involvement of universities is crucial to identify how Cleaner Production strategies are formed in practice so that companies integrate sustainability into their strategies. This paper discusses the experience of establishing and operating the Cleaner Production Center at the University of Cienfuegos. From 2008 to 2011, the University of Cienfu...

The urban quality of life (UQoL) from objective dimension was analyzed in the main Cuban cities. An Urban Quality of Life Index (UQoLI) was developed in collaboration with 60 experts (five in each city). These experts belong to one of two categories: in charge of the planning of the city and members of the Municipal Council of Administration. One h...

A quantitative assessment of the environmental impact of construction activities is useful to identify the main environmental impacts and to improve their environmental footprint. This study presents the life cycle assessment of an earthwork project. The results show that earthwork activities entail important environmental impacts; mainly energy co...

Calcium oxide (CaO), commonly known as lime or quicklime, is an energy intensive product. In order to produce lime, vertical shaft kilns are widely used in the lime industry. The objective of this work is to analyze the energy and exergy consumption