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Copyright of Energetika is the property of Lithuanian Academy of Sciences Publishers and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In developing countries, residual biomass usage by means of anaerobic digestion offers several benefits and opportunities, such as a sustainable energy source, production of organic fertilizers and new agrobusiness models. In Latin America, Colombia is one of the most promising markets for the implementation of this technology in terms of availability of biomass and economic growth, as recently reported by local government organizations. In this paper, special attention is given to Antioquia, a department of Colombia with the largest farms of cattle and pigs, according to information reported in 2018 by the Ministry of Agriculture and Rural Development. It is estimated that manure from the porcine subsector in Antioquia has an approximate technical-energy potential of 1,896 TJ year-1, varying from 1,611 to 2,186 TJ year-1, corresponding to the 95% confidence interval. In the case of manure generated by the livestock subsector in Antioquia, it is estimated a theoretical energy potential of 8,566 TJ year-1. However, traditional extensive production systems disseminate manure through the pastures turning centralization of the available residual biomass a difficult task and not senseful. Based on the local practices of the specialized dairy subsector, it is estimated that manure collected during the milking process could reached up to 25% of the total available. Biochemical conversion of this amount of biomass has an estimated technical-energy potential of 187 TJ year-1, varying from 156 and 236 TJ year-1, corresponding to the 95% confidence. The aim of this article is to estimate the technical-energy potential for the livestock and porcine subsectors in the Department of Antioquia, based on the available residual biomass according to local farming practices. [ABSTRACT FROM AUTHOR]

Copyright of Revista Ciência e Natura is the property of Revista Ciencia e Natura and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The objective of this research was to analyze energy security in Ecuador, which is interconnected with water and food security. As a methodology, 21 indicators grouped into the following dimensions were analyzed: availability, infrastructure, energy prices, efficiency, social impact, environment and governance. For each indicator, a cross-sectional analysis was carried out with the countries of Colombia, Peru and Bolivia, along with a longitudinal analysis from 2011 to 2021. The main contribution of this study is the characterization of the Ecuadorian energy system as available, accessible, affordable and renewable in an electrical matrix but inefficient and heavily dependent on fiscal resources. The factors that may affect Ecuador's energy security were determined to be the risk of a reduction in income due to it becoming a net importer of energy, climate change, socio-environmental conflicts, poor diversification, energy subsidies and weak governance. A policy is proposed aimed at decoupling development from fossil fuels, with a systemic vision considering the complexity of interactions with other economic sectors, such as water and food, among others. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Applied Economics / Economía Aplicada is the property of FEA-RP, Universidade de Sao Paulo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Acta Bioéthica is the property of Universidad de Chile, Centro Interdisciplinario de Estudios en Bioetica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The vulnerability of electric potential generation from water resources has been evidenced due to uncertainties of climatic origin and energy planning. Changes in rainfall regimes are multifactorial phenomena difficult to model. Rainfall is the main natural way of restoring the reservoir levels of hydroelectric power plants. The reduction in rainfall levels may increase in the coming years, resulting in a probable change of the energy matrix configuration of the state of Minas Gerais (MG). This could reduce the share of renewable sources increasing dependence on the importance of energy from fossil fuels, which are the immediate primary sources of energy available. Prior examinations have portrayed the depletion of hydroelectricity in Brazil, or its macro-regions, however this work tries to supply a more focused look at the effects on the electricity and social sectors of the state of Minas Gerais. The study developed in this paper aims to investigate the hydrological potential alteration impacts and consequences on the energy matrix of the state, the greenhouse gas emissions and the social reflexes of these changes due to scenarios motivated by climate change. The investigation intends to show the importance of the water-energy-emissions nexus for energy planning and decision-making, in order to evaluate the best options for dealing with adverse and potentially destabilizing conditions. The results of the analyses show that while hydropower demand was 5.24 Mtoe in 2015, in 2030 the supply of hydropower will be 5.81 Mtoe and 4.72 Mtoe, for the conservative and severe scenarios, respectively. In addition, the effect of climate change may require an increase in the share of non-renewable sources in the energy matrix, which could increase CO 2 e emissions from 4.2% to 7.4% by 2030, compared to the levels in 2016. • Reduction in rainfall levels will change the energy matrix configuration of MG state. • Population growth will boost demand for energy. • It is shown the importance of the water-energy-emissions nexus for energy planning and decision-making. • The energy matrix may considerably increase the CO 2 e emissions by 2030, compared with 2016 levels in the MG state. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Wood Science / Revista Ciência da Madeira is the property of Brazilian Journal of Wood Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

China is leading the world in research, development and investment in the renewable energy industry. This long-term strategic initiative has important consequences not only for China's own growth, but also for world sustainable development. During the last hundred years, countries have relied on petroleum as their main energy source. However, this is unsustainable. The world has reached a point in which leaders will have to make decisions about the new energy matrix for the next 50 years. Early innovators will have access to new information and knowledge and, thus, will most likely be the leaders of tomorrow. This paper assesses where the United States stands within the clean energy revolution and the threats arising from an ambitious China. [ABSTRACT FROM AUTHOR]

The energy matrix is a useful tool for understanding the trends of production and consumption in a country and for evaluating long-term energy policies. This paper presents a behavioral simulation model of the evolution of Chile’s energy matrix. The model is developed and calibrated by considering a dynamic substitution of energy sources. Chile’s stated policy is to become less dependent on imported fossil fuels, to increase security of supply and improve the environment. The simulation experiments show that the energy matrix is very robust with regards to external fuel prices and changes in investment cost. Thus, in order to be able to observe changes in the composition of the energy matrix, there is a need for strong intervention by the regulator, or the government, to provide incentives for renewables. [ABSTRACT FROM AUTHOR]

Climate change might affect energy production and therefore the energy security of a country or region. This situation may impact renewable energy sources such as hydro power, leading to consequences on energy transition strategies. This might be critical in sensitive regions to climate change, one of them being the Caribe and northern South America. Since there are numerous energy systems based on sensitive technologies worldwide, it is necessary to introduce techniques to analyze the effects of climate change on different possible energy transition paths. The goal of this study is to develop and assess a method to analyze one of the most critical effects faced by climate change for societies worldwide: the sensitivity of the energy systems to climate change. This is especially critical in developing countries, in locations where temperatures will strongly increase in the following years. To assess this effect, this study proposes a vulnerability index (VI) to evaluate the vulnerability of an on-grid electricity system to climate change at the national and regional scales. This index was assessed using a Monte-Carlo method for uncertainty. The case of Colombia, a country with a system based on hydropower (> 70%) is used to illustrate the method. VI is based on variables related to climate change, the energy matrix, and vulnerability. Results show that the regions with the larger vulnerability correspond to the more energy-demanding ones. The VI for these regions is greater than 50% of the maximum possible vulnerability; meanwhile, the vulnerability of the whole country was estimated as 43%. [ABSTRACT FROM AUTHOR]

Increasing awareness of climate change has induced demand for action most notably. As public demand for action on climate change increases, conversion to energy sources with lower greenhouse gas (GHG) intensity will accelerate. Experience during the COVID-19 pandemic provided insight into how atmospheric conditions will respond to lower GHG emissions. A low-carbon future will require decarbonization of the energy supply mix for electrical production and industrial processes. Coal demand likely will decrease more rapidly than other fossil energy sources, replaced by natural gas and renewable energy sources that have lower GHG intensity and that will be available readily and economically. This decline will accelerate as China focuses on its carbon neutrality goals, the U.S. re-engages in the Paris Agreement, and India moves to a lower carbon future. However, perturbations in the decline will inevitably occur in response to global issues (e.g., pandemic, military conflict). Carbon capture, utilization, and storage (CCUS) technologies can reduce GHG emissions from coal as an energy source, but the capital and operation costs of CCUS remain high, which translates to slow commercial deployment. In this study, a literature review and interviews with industry experts and business leaders were conducted to understand the current and projected role of fossil fuels, primarily coal, in the global energy matrix; present their contributions to GHGs; analyze the effects of social expectations and climate policy on energy choices and coal demand; and describe the expected impacts on coal production for decades to come. [ABSTRACT FROM AUTHOR]

• Proposed an intelligent approach for transmission line fault analysis based on capsule network. • An unsupervised model is developed which requires no manual labeling of the data. • The performance against line parameter variation and high impedance faults is assessed. • Noises are considered to justify the robustness of the proposed approach. • The performance is compared with the baseline capsule network and existing approaches. Detection and classification of transmission line (TL) faults are key factors for the fault root cause analysis and rapid restoration of the power network. Deep learning can extract representative features automatically from big data, thus becoming an important breakthrough in fault analysis. Existing deep learning-based fault diagnosis models rely on a large number of data obtained from a variety of fault conditions to be generalized. Indeed, in the TL domain, it is difficult to define and, therefore to collect the fault incepted features of all possible fault scenarios. This paper proposes an unsupervised framework for fault detection and classification (FDC) of TL based on a capsule network (CN). Instead of using the baseline CN, an extension to this with a sparse filtering technique is adopted in this work. The capsule network with sparse filtering (CNSF) voluntarily learns the expensive fault features and significantly improves the model performance without involving a large number of data. The proposed scheme receives 1 / 2 cycle post-fault three-phase signals and encodes them into a single image that is defined as the input for the proposed CNSF model. The effectiveness of the proposed CNSF model is corroborated by four different TL topology confirming the model's adaptability to a topology change in response to intended control action or the switching actions due to cascading faults. Further assessment of the model's performance against noise, high impedance faults (HIF), and line parameter variations are also carried out in order to confirm the high reliability of the proposed model. In addition, a rigorous comparative study is conducted to guarantee the state-of-the-art performance of the proposed model. [ABSTRACT FROM AUTHOR]

This paper is a compact version of the 2005 São Luís/ABN AMRO Bank winning monograph that aimed at studying the economic viability of building bioreactors in firms to produce biogas. Firms responsible for generating high volumes of waste can benefit enormously from this implement both to produce their own energy and to discard residues. The latter can also become a rich fertilizer at the end of a process called biodigestion. The article brings studies of bioreactors located in developing and developed nations, as well as a pilot project which has been specially designed by the author for the citrus industry. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Management / Revista de Administração da UFSM is the property of Brazilian Journal of Management / Revista de Administracao da UFSM and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista EIA is the property of Escuela de Ingenieria de Antioquia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article addresses a dialogue process regarding the implementation of an energy policy based on the development of wind power in Uruguay. This policy is the major component of a national strategy of diversification of the energy matrix based on renewable sources initiated by the Uruguayan government in 2005. We focus on the development of a cognitive niche regarding wind energy emphasizing a virtuous articulation between academia and government. Results are presented as a narrative of the development of wind energy engaging with the literature on technological transitions and innovation systems. The transition resembles a transformation path in three phases during which relationships among different communities evolved. The analysis addresses the importance of learning spaces on energy-related topics and the leading role of the State in the transformation. [ABSTRACT FROM AUTHOR]

Four typical flow patterns in the vertical pipe of the dense‐phase pneumatic conveying of pulverized coal were obtained, namely packed bed flow, plug flow, churn flow and less dense phase flow. The electrical capacitance tomography (ECT) was used for space–time multiscale analysis. Firstly, Daubechies second order wavelet transform and rescaled range analysis(R/S) were applied for the scientific multiscale decompositions. The multiscale frequency range is that the microscale signal is d1–d5 (2.1875, 70.0000) Hz, the mesoscale signal is d6 and d7 (0.5469, 2.1875) Hz and the macroscale signal is d8–d11 (0.0342, 0.5469) Hz. The multiscale ECT signal characteristics of pure gas flow, particle–wall friction, and particle–particle collision were determined by experiments. The multiscale ECT signal energy matrix is proposed, based on the multiscale energy structure characteristics. Control mechanisms and multiscale statistical rules of four typical flow patterns are obtained. This study provides theoretical support for the study of flow pattern transformation of dense‐phase pneumatic conveying. [ABSTRACT FROM AUTHOR]