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This study presents a conceptual design of an Internet of Things (IoT) communication system for monitoring power generation systems in Colombian Non-Interconnected Zones (NIZs), which lack IoT connectivity due to complex geographical factors. The proposed system aims to ensure the proper operation and energy efficiency of off-grid systems while tracking the variables that influence their performance.The methods used in this study include identifying the needs of such a system, identifying requirements, obtaining technical specifications, and developing a conceptual design. The study also analyses and compares various technologies, including Wi-Fi, Bluetooth, LoRa and ZigBee, to determine which ones are best suited for IoT system design.The conceptual design of the proposed IoT monitoring system considers the geographical, communication and coverage characteristics of the NIZs and the technical characteristics of the energy projects to provide a complete functional system that can connect approximately 2 million people located in these isolated and vulnerable zones. Finally, the defined system can serve as a precedent for building prototypes in various NIZs, and research on IoT technologies suitable for NIZs can help us seek the technologies that are most suitable for these areas. Depending on the application and conditions of the energy project, the most appropriate technology can be determined on a case-by-case basis.

Catalytic conversion of lignin to value-added aromatic compounds is still an open challenge, since the selective cleavage of the linkages interconnecting the aromatic molecules, especially the β-O-4 ones, is not efficiently achieved yet. Herein, novel titania-based nanostructured materials were synthesized using low-power-low-frequency ultrasound that demonstrated high efficiency for the selective cleavage of Cα-Cβ bond of β-O-4 linkages of lignin-inspired model compounds. Going a step ahead, experiments of sonophotocatalytic valorization of 2-phenoxy-1-phenylethanol were contacted for the first time, where the exposure to ultrasound leading to better conversion and selectivity towards the desired products in the case of the novel ultrasound-synthesized nano-photocatalyst. Mechanistic insights showcased that photogenerated holes are the main active species in the catalytic process. In general, this research work provides a green, effective, and cost-effective approach for the selective and efficient catalytic lignin valorization.

AbstractThe rapid depletion of fossil fuel reserves, population growth, and increasing environmental pollution have forced a change in the search for alternatives to produce and use energy. Currently, renewable energies (RE) have achieved more efficient advances to produce energy from non-conventional and inexhaustible sources, which can meet the basic needs of society and whose environmental impact is a door of opportunities for all. For this reason, academia has a preponderant role in ensuring that engineers are fully equipped with the necessary skills to provide feasible and contextualised solutions for this era of energy transition framed by the UN Sustainable Development Goals (SDGs). This article explores the impact on the development of the necessary skills for engineers in the renewable energy sector by tracing a route towards the acquisition of renewable energy knowledge with strategically organised work teams of undergraduate students, where two methodologies that are gaining ground in engineering education programs are applied: Problem Based Learning(PBL)and Design thinking (DT).After the validation of these techniques, it is concluded that bringing engineering students closer to real contexts related to renewable energies and above all with an objective of impact on communities, it is the right way to build knowledge in teams, in an immersive and committed way with the institution, which has developed and implemented an innovative pedagogical method based on the application of a critical educational model focused on the development of competencies, where the union of new technologies with the teaching processes on which this research is based is envisioned for the future.

The research for “green” and economically feasible approaches such as (photo)catalysis especially for biomass valorization such as selective oxidation of biomass derived compounds like aromatic alcohols to corresponding aldehyde by avoiding the harsh reaction conditions and the addition of reagents concentrate the focus of attention the last years. Hence, design and development of novel photocatalyst for the partial selective oxidation is highly desirable. In this research work, ultrasonication of different frequencies (22, 40, 80 kHz) and different amplitudes was utilized as synthesis tool in order to obtain novel materials by precipitation method. The synthesized samples were characterized by using different techniques such as N2 sorption, TEM, XPS, XRD, thermal analysis, and diffuse reflectance spectroscopy. The synthesized sample by using low ultrasound frequency (22 kHz) and amplitude showed a mixed morphological and structural nature consisting of asymmetric 1-dimensional (nanorods-like), layered nano-structures and not well-defined areas, leading to elevate for metal oxide specific surface areas up to 155 m2/g. The observed 1-D nanostructures have diamentions in the range of 20–60 nm. This sample revealed the highest photo-oxidation efficiency for the selective conversion of two biomass-derived, and more specifically lignin-inspired model compounds, benzyl alcohol and cinnamyl alcohol to benzaldehyde and cinnamyl aldehyde, respectively, and hence the highest yield towards the desired aldehydes. The selective photo-oxidation activity was retained even after 5 photocatalytic cycles, while no leaching of Ti was recorded.

The designing and synthesis of novel photocatalysts are the most important parts, with TiO2-based materials to be consider as prosperous candidates for the selective photo-oxidation of aromatic alcohol. Herein, we established an ultrasound-assisted (500 kHz) precipitation synthetic protocol which led to titanate nanorods of 30 nm maximum length, decorated with nanoclusters of size 1–3 nm. The physicochemical features of the synthesized catalysts were characterized by various techniques. The 1-D nanomaterial obtained at low ultrasound power revealed highest yield towards selective photo-oxidation of benzyl alcohol to benzaldehyde comparing to the material synthesized at higher ultrasound power, in silent, and the commercial TiO2-P25.

The challenge of improving the activity of TiO2 by modifying it with metals and using it for targeted applications in microreactor environments is an active area of research. Recently, microreactors have emerged as successful candidates for many photocatalytic reactions, especially for the selective oxidation process. The current work introduces ultrasound-assisted catalyst deposition on the inner walls of a perfluoro-alkoxy alkane (PFA) microtube under mild conditions. We report Cu-Au/TiO2 and Fe-Au/TiO2 nanoparticles synthesized using the sol–gel method. The obtained photocatalysts were thoroughly characterized by UV–Vis diffuse-reflectance spectroscopy (DRS), high-resolution scanning electron microscopy (HR-SEM), high-resolution transmission electron microscopy (HR-TEM), X-ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and N2 physisorption. The photocatalytic activity under UV (375 nm) and visible light (515 nm) was estimated by the oxidation of lignin-based model aromatic alcohols in batch and fluoropolymer-based flow systems. The bimetallic catalyst exhibited improved photocatalytic selective oxidation. Herein, four aromatic alcohols were individually investigated and compared. In our experiments, the alcohols containing hydroxy and methoxy groups (coniferyl and vanillin alcohol) showed high conversion (93% and 52%, respectively) with 8% and 17% selectivity towards their respective aldehydes, with the formation of other side products. The results offer an insight into ligand-to-metal charge transfer (LMCT) complex formation, which was found to be the main reason for the activity of synthesized catalysts under visible light.

Energy determines the social, economic, and environmental aspects that enable the advancement of communities. For this reason, this paper aims to analyze the quality of the energy service in the Non-Interconnected Zones (NIZ) of Colombia. For this purpose, clustering techniques (K-means, K-medoids, divisive analysis clustering, and heatmaps) are applied for data analysis in the context of the NIZ to identify patterns or hidden information in the Colombian government data related to the state of the electricity service in these localities during the years 2019–2020. A descriptive statistical analysis and validation of the results of the clustering techniques is also carried out using R software. Through the implementation of clustering algorithms such as K-means, K-medoids, and divisive analysis clustering, potential areas for the development of renewable and alternative energy projects are identified, considering places with deficiencies in their current electricity service, higher consumption, or places with very low daily hours of electricity service. Additionally, relationships were identified in the dataset that can be considered as tools that would support decision-making for academia and industry, as well as the definition of guidelines or strategies from the government to improve energy efficiency and quality for these places, and consequently, the living conditions of the residents of Colombia’s NIZs.

The continuous increase of the demand in merchandise and fuels augments the need of modern approaches for the mass-production of renewable chemicals derived from abundant feedstocks, like biomass, as well as for the water and soil remediation pollution resulting from the anthropogenic discharge of organic compounds. Towards these directions and within the concept of circular (bio)economy, the development of efficient and sustainable catalytic processes is of paramount importance. Within this context, the design of novel catalysts play a key role, with carbon-based nanocatalysts (CnCs) representing one of the most promising class of materials. In this review, a wide range of CnCs utilized for biomass valorization towards valuable chemicals production, and for environmental remediation applications are summarized and discussed. Emphasis is given in particular on the catalytic production of 5-hydroxymethylfurfural (5-HMF) from cellulose or starch-rich food waste, the hydrogenolysis of lignin towards high bio-oil yields enriched predominately in alkyl and oxygenated phenolic monomers, the photocatalytic, sonocatalytic or sonophotocatalytic selective partial oxidation of 5-HMF to 2,5-diformylfuran (DFF) and the decomposition of organic pollutants in aqueous matrixes. The carbonaceous materials were utilized as stand-alone catalysts or as supports of (nano)metals are various types of activated micro/mesoporous carbons, graphene/graphite and the chemically modified counterparts like graphite oxide and reduced graphite oxide, carbon nanotubes, carbon quantum dots, graphitic carbon nitride, and fullerenes.

The implementation of renewable energy is a necessity nowadays and like any other technology involves challenges and opportunities to achieve. The main objective of our projects in an off-grid vulnerable community in Colombia is to design a smart grid to control the power grid, but also to understand the grid behavior and the actors (generators and consumers) for which a smart monitoring system must be implemented in the initial phase of these initiatives. This work proposes the design of a smart monitoring sensing system to gather information on both the status of electrical variables (i.e., power, current, voltage, reactive energy, and power factor) and environment variables (i.e., temperature, solar radiation, GPS, humidity, and atmospheric pressure) for an off-grid renewable energy system fit for a vulnerable community in Colombia. The system was created as a web-app that allows multiplatform access and allows scalability for large numbers of generators and loads. Finally, the system offers flexibility to exploit different sensors or hardware to measure the variables since it only reads the information from the data base.

This article presents a methodology for automatic fault detection in photovoltaic arrays. Due to the great importance in the construction of increasingly robust photovoltaic plants, automatic fault detection has become a necessary tool to extend the useful life of these plants, avoid system shutdowns and reduce serious safety problems. In the present study, nine possible faults are detected, caused by malfunction in the bypass and blocking diodes. The solution consists of training two models based on artificial neural networks, the first model is a binary classifier that detects whether or not a fault occurs, the second is a multiclass classifier that detects the fault type. The obtained models were trained from simulation data, in an architecture of 9 photovoltaic panels interconnected in three rows by three columns matrix (extendable to larger systems). The evaluation shows that the prediction system has a total accuracy of 92.95%. Finally, this methodology is intended to be implemented in Colombia, in zones with difficult access and not interconnected to the electricity grid, seeking to reduce corrective maintenance.

This study seeks to analyze different energy solutions for the Kanalitojo Indigenous Community that is located 25 kilometers from the municipal seat of the municipality of Puerto Carreño, in the State of Vichada, eastern Colombia. For the development of this study, a technical performance analysis has been applied to each proposed solution considering the amount of electricity generation and demand. The first solution refers to a hydrokinetic turbine connected to a distribution network. The second solution combines the use of solar panels, hydrokinetic turbine, and portable batteries with which it is possible to transport the generated energy to the places where the community needs it. The third proposed energy solution refers to the use of micro-cogeneration units and portable batteries. With the use of the capabilities of the TRNSYS v17 energy simulation software, the comparative technical analysis between each solution for the same load demand is carried out. This analysis has shown a great advantage in the use of solar panels, hydrokinetic turbine, and portable batteries with an electricity surplus of 103.8%. However, technically the first solution based on a hydrokinetic turbine is more suitable for the community challenges due to it meets the electricity demand of the community by an excess of 12.4% and the capital and operating expenditure are less.

The degradation of air quality, overheating and growing energy demand are closely related issues that indicate the impact of humankind on climate change. Consequently, governments and other multilateral agencies have shown interest in reducing air pollutant emissions from fossil fuel power generation sources. The most accepted options are related to clean energy sources, but, as we all know, we are far from meeting the world’s energy demand with clean generation sources. Other options are based on using fuels with a lower load of emissions and on the development of techniques to optimise power generation, reduce costs through efficient energy and reduce greenhouse gas emissions to the possible minimum. This study proposes a method to optimise the sensitivity factors as the operating point for a gas turbine power generator based on energy demands, electrical efficiency, fuel efficiency and the minimisation of greenhouse gas emissions. In order to address this, a multidisciplinary design/assessment framework was developed. The results obtained from the simulation of a one-year energy consumption model for an average family in Colombia produced the point of operation for a gas turbine based on energy demands, efficient energy and the reduction of CO2 emissions to the atmosphere (i.e. the best trade-off). In this sense, the main contribution of this work is aimed at energy generation systems bio-inspired optimisation that reduce CO2 emissions into the atmosphere, especially in non-interconnected (off-grid) zones, but they rely on fossil fuel plant-based-power distributed generation.

The industrial and economic development of the industrialized countries, from the nineteenth century, has gone hand in hand with the development of electricity, the internal combustion engine, computers, the Internet, data use, and the intensive use of knowledge focused on science and the technology. Most conventional energy sources have proven to be finite and exhaustible. In turn, the different production activities of goods and services using fossil fuels and conventional energy have significantly increased the pollution of the environment, and with it, contributed to global warming. The objective of this work was to carry out a theoretical approach to data analytics and business intelligence technologies applied to smart electrical-system networks with renewable energies. For this paper, a bibliometric and bibliographic review about Big Data Analytics, ICT tools of industry 4.0 and Business intelligence was carried out in different databases available in the public domain. The results of the analysis indicate the importance of the use of data analytics and business intelligence in the management of energy companies. The paper concludes by pointing out how business intelligence and data analytics are being applied in specific examples of energy companies and their growing importance in strategic and operational decision-making.

This work aims to evaluate the provision of energy services in non-interconnected zones (NIZ) between 2018 and 2019 using open data from the Colombian government and business intelligence methodology. The analysis is approached from the ETL (Extract, Transform, Load). It focuses on the variables obtained from the National Monitoring Centre (CNM) for monitoring the operation of these zones, where there is a Telemetry System that provides monthly information on location variables, energy variables, such as active and reactive energy maximum power, maximum power per day, and hours of service delivery. We concluded that in the years, 2018–2019 energy consumption in NIZ has remained stable with a variation of 0.19%. On the other hand, the NIZ include 56% of Colombia’s states, and the energy consumption is concentrated in 6 of the 93 municipalities with 80% of national consumption. The challenges in these areas are associated not only with the quality and provision of energy services but also with the environmental challenges that mean that most of these areas obtain their energy supply from fossil fuels, being protected areas such as ecological reserves, the biosphere, or the jungle.

The off-grid communities in Colombia are characterised by the diversity of their geography, socio-cultural contexts, and structures of the system. Despite their potential, the opportunities for access to energy and therefore other conditions to develop education, productivity, health, technological projects, and recreation are highly limited. Under those conditions, the implementation of projects with water and/or energy solutions based on renewable sources would bridge the gaps of isolation and social marginalisation that have detained the future of these communities for years. Projects around water and/or energy require the input of external stakeholders to communities, despite of the willingness to change their realities towards a better lifestyle. To achieve a common point of interests among stakeholders, the dialogues, the understanding of the community cosmovision and the ethical perspectives regarding the use of natural resources are needed. Furthermore, it is necessary to identify perceptions of confidence and risk of renewable energy projects within the community. To design water and/or energy solutions based on the abovementioned in a sustainable manner, the framework “Community, wAter-Renewable Energies, Diversity” CARED is being developed, for which the first phase in its implementation is presented. The process has been carried out in the Wayuu indigenous community “La Paz” located nearby Manaure in La Guajira state in the northeast of Colombia.

Different efforts have been carried out in the last years in order to find some alternatives for fossil fuels. Biofuels have been considered as one of the possible substitutes for fossil fuels because the majority of vehicles and co-generation systems can use them without any modification and produce fewer emissions. Additionally, some developing countries are presented as a good location for biofuels production due to their weather, economic and social conditions. The methodology used in this study is as follows: firstly, the current drivers and barriers that affect the production of biofuels in Colombia were identified in the available literature. The results showed Colombia presents some special conditions for the production of biofuels that allow it to generate a competitive advantage compared to other countries. However, some barriers can affect the adoption and production of biofuels in the country. Secondly, a survey was realised to biofuel producers, suppliers and researchers in order to validate their motivations and perceptions. Some similitudes and differences with regard to the literature were found in the surveys. Hence, this information allowed the authors to understand the reality of biofuels in Colombia from the views of the stakeholders. Additionally, a set of policies were analysed. The authors believe that this set of policies will help stakeholders to have a better production of biofuels in Colombia.

Flight route planning in civil aviation seeks to minimize the total cost of the operation while maintaining high safety standards. Therefore, the increase in the number of air routes as well as air traffic in commercial aviation poses new challenges for planning optimal routes. This work proposes a method to plan routes using a bio-inspired technique called Particle Swarm Optimization (PSO). Such method aims to obtain the shortest distance between two points, thus reducing NOX, CO2 and H2O emissions. The analysis of fuel consumption and emissions was carried out using a multidisciplinary simulation tool, the Preliminary Multidisciplinary Design Framework (PMDF). The latter was applied to an aircraft with a conventional configuration powered by an innovative turbofan engine. The planner provides a new route with the shortest possible flight distance and, at the same time, considers unexpected obstacles on the route, thus minimizing fuel consumption and possible polluting emissions into the atmosphere. This is one of a series of works that will use the proposed design tool. Different economic and environmental scenarios will be evaluated once such studies are concluded.

In conventional aviation, flight route planning aims to guarantee security and reduce the operating costs of the different types of aircraft that are currently available. This paper presents and analyses the results obtained from planning a flight route in real time for short-range aircraft fitted with geared turbofans with a constant volumecombustor to reduce operating costs by optimizing the route in terms of less distance traveled. In the analysis, an off-line route obtained from a flight profile using the Preliminary Multidisciplinary Design Framework tool is compared with the same route that is run in real time using a route planner optimized with a particle swarm optimization algorithm. The average results indicate that the route proposed by the optimization algorithm reduces direct and indirect operating costs if compared to the alternative route (traditional approach according to flight plan). This is mainly due to the lower fuel consumption and maintenance costs when selecting an optimized route. In cases where direct and alternate routes are completely obstructed, the planner can find an optimized route based on the lower costs. In this way, the pilot and the flight controller on the ground can make the decision whether to risk the aircraft with passengers on a route with adverse weather conditions or to have an optimized and safe one. The use of this type of route optimizer leads to significant benefits with respect to aircraft environmental taxes for emissions and noise, and increases aviation safety. This finding indicates that the route planner is a suitable support option when the course of an aircraft must be changed to follow a different route than the suggested alternative.

Use of sonication for designing and fabricating reactors, especially the deposition of catalysts inside a microreactor, is a modern approach. There are many reports that prove that a microreactor is a better setup compared with batch reactors for carrying out catalytic reactions. Microreactors have better energy efficiency, reaction rate, safety, a much finer degree of process control, better molecular diffusion, and heat-transfer properties compared with the conventional batch reactor. The use of microreactors for photocatalytic reactions is also being considered to be the appropriate reactor configuration because of its improved irradiation profile, better light penetration through the entire reactor depth, and higher spatial illumination homogeneity. Ultrasound has been used efficiently for the synthesis of materials, degradation of organic compounds, and fuel production, among other applications. The recent increase in energy demands, as well as the stringent environmental stress due to pollution, have resulted in the need to develop green chemistry-based processes to generate and remove contaminants in a more environmentally friendly and cost-effective manner. It is possible to carry out the synthesis and deposition of catalysts inside the reactor using the ultrasound-promoted method in the microfluidic system. In addition, the synergistic effect generated by photocatalysis and sonochemistry in a microreactor can be used for the production of different chemicals, which have high value in the pharmaceutical and chemical industries. The current review highlights the use of both photocatalysis and sonochemistry for developing microreactors and their applications.

Las iniciativas locales en el marco de la acción política de la resistencia social están encaminadas a solucionar contextos complejos, problemas puntuales y propios de una determinada comunidad. Así su cobertura sea reducida porque se limita a lo local, ha sido valioso su impacto en términos de bienestar. Pequeñas organizaciones locales han creado sus propios espacios para poder ac- tuar, a veces, en concordancia con las políticas públicas establecidas y otras de manera absolutamente creativa y autónoma. Así, la población se ha organizado para defender los derechos humanos, prevenir el reclutamiento o para buscar la resolución pacíęca de conĚictos. Exploran los alcances de la educación y la cultura para la paz y la manera de proteger a la infancia de un destino que no ofrezca opciones a la vida. Reconstruyen familias y comunidades enteras para que las víctimas retomen una vida independiente y económicamente viable, para que desvinculados de los grupos armados ilegales se reintegren a la legalidad, en ęn, realizan acciones concretas que, en pequeña escala, son esfuerzos tangibles de resistencia social. Es inmenso el universo de acciones especíęcas que salvan vidas, reparan daños, frenan las acciones violentas o fortalecen las acciones colectivas y el valor civil para sobreponerse a ellas. Todas son expresión del esfuerzo local para resol- ver una situación concreta pero, al mismo tiempo, tienen la capacidad de incidir en las políticas públicas locales, como ya lo han demostrado algunas comunidades que se abordaran en este documento.

Heterogeneous photocatalysis offer many possibilities for finding appropiate environmentally friendly solutions for many of the the problems affecting our society (i.e., energy issues). Researchers are still looking for novel routes to prepare solid photocatalysts able to transform solar into chemical energy more efficiently. In many developing countries, biomass is a major energy source, but currently such countries lack of the technology to sustainably obtain chemicals and/or fuels from it. The Roadmap for Biomass Technologies, authored by 26 leading experts from academia, industry, and government agencies, has predicted a gradual shift back to a carbohydrate-based economy. Biomass and biofuels appear to hold the key to satisfy the basic needs of our societies for the sustainable production of liquid fuels and high value-added chemicals without compromising the scenario of future generations. In this review, we aim to discuss various design routes for nanostructured photocatalytic solid materials in view of their applications in the selective transformation of lignocellulosic biomass to high value-added chemicals.

TiO2 (anatase phase) has excellent photocatalytic performance and different methods have been reported to overcome its main limitation of high band gap energy. In this work, TiO2-magnetically-separable nanocomposites (MAGSNC) photocatalysts with different TiO2 loading were synthesized using a simple one-pot mechanochemical method. Photocatalysts were characterized by a number of techniques and their photocatalytic activity was tested in the selective oxidation of benzyl alcohol to benzaldehyde. Extension of light absorption into the visible region was achieved upon titania incorporation. Results indicated that the photocatalytic activity increased with TiO2 loading on the catalysts, with moderate conversion (20%) at high benzaldehyde selectivity (84%) achieved for 5% TiO2-MAGSNC. These findings pointed out a potential strategy for the valorization of lignocellulosic-based biomass under visible light irradiation using designer photocatalytic nanomaterials.