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Techno-Economic Analysis of Microgrids with Distributed Energy Resources in Rural Limpopo Province, South Africa
No full textMSC in PhysicsDepartment of PhysicsThe United Nations' sustainable energy development portfolio indicates that around 1.3 billion people globally still lack access to grid-based electricity, underscoring the urgent need for sustainable energy solutions. In Sub-Saharan Africa, about 13% of the population faces limited electricity access due to challenging terrains, inadequate energy policies, and insufficient investment. High costs of extending the electrical grid further complicate the issue. Regions with potential for renewable energy resources, such as solar and wind, offer opportunities to improve energy access. In South Africa's Limpopo province, while the electrification rate is 96%, some rural areas remain without electricity due to poor grid infrastructure and unreliable supply caused by load shedding and load reduction. Even where electricity is available, rising energy costs pose a significant burden on economically disadvantaged communities. This deficit of energy supply in rural areas needs attention through microgrid optimisation.
This research aims to techno-economically analyse the feasibility of optimising microgrids in rural Limpopo province, focusing on adopting a system with the least net present cost and levelized cost of energy. Three objectives are the main drive to achieve the aim of this research. The first objective is to provide a review of available and potential renewable energy resources in Limpopo province, focusing on their operational status. Currently, solar PV, biomass, and biogas are available, while geothermal, hydropower, and wind are potential resources. The second objective is to analyse the technical and economic aspects of microgrid optimisation to assess its implementation feasibility without hydrogen production. The third objective evaluates the same elements to determine the feasibility of microgrid implementation with hydrogen production.
The Herman-Beta method was employed for peak load estimation, while Homer Pro analysed maximum daily consumption, developed load profiles, and simulated microgrid configurations. The analysis comprised two parts: one focused on microgrids without hydrogen production and the other with it. The first part evaluated PV/Grid and PV/BES/Grid configurations to identify the optimal microgrid solution for each region. For the hydrogen production configurations, three types of PV modules (250 W, 375 W, and 500 W) with a 48V, 14.4 kWh lithium battery were tested, including PV/H2/Grid and PV/BES/H2/Grid setups.
Microgrid optimisation results without hydrogen production show that the PV/Grid configuration is the most cost-effective option across all areas. For Ga-Masekwa, the LCOE is 2.356 R/kWh with an NPC of R 5.4 M. For Ka-Dzingidzingi, the LCOE is 1.292 R/kWh and NPC R 76 M; for Duthuni, 1.216 R/kWh and R 138.7 M; and for Mookgophong NU, 1.197 R/kWh and R 250.3 M. The findings on microgrids with hydrogen production show that the
PV/H2/Grid configuration is the most cost-effective, offering the lowest NPC and LCOE, and a high return on investment. However, producing green hydrogen requires significant energy, increasing the overall system cost.
Conducting a techno-economic analysis of microgrids with distributed energy resources is essential for assessing their feasibility, sustainability, and cost-effectiveness. This study aids in cost-benefit evaluations, system optimisation, financial risk assessments, and the development of resilient alternative energy systems.University of Venda and Department of Higher Education's Nurturing Emerging Scholarship Programm
An economic performance overview of microgrids for Limpopo province rural areas
No full textA review of the economic viability of microgrids has been of high significance, considering the readiness of the global community to advance alternative energy generation resources from fossil fuels. Rural areas have been a critical point of various renewable energy studies due to electrification challenges in most rural areas worldwide. This review is driven by the fact that limited access to electricity affects rural communities' daily economic activities and social empowerment security. This limited access is due to a lack of electrification and generation capacity shortage as electricity demand increases due to population growth. We are conducting this study to explore new ways to bring affordable and dependable electricity to the rural areas of Limpopo province. This paper presents an economic review of implementing population size-dependent microgrids in the province. Four random rural areas with different population sizes have been selected. These areas have almost the same global solar horizontal irradiance and temperatures. The study areas are Ga-Masekwa, Ka-Dzingidzingi, Duthuni, and Mookgopong NU. The Herman-Beta method for peak load estimations and Homer Pro software have been employed to estimate location load profiles and simulate microgrid configurations. The study analyzed different solar power configurations, including solar PV/grid, solar PV/battery, and solar PV/grid/battery, to determine the best microgrid for each area. The results showed that the solar PV/grid configuration is the most cost-effective, with the least net present cost (NPC), levelized cost of energy (LCOE), and high returns of investments. The NPC of study areas sequentially is 284211,4M, 7.3M,and13.2M, respectively, and their levelized cost of energy is 0.124/kWh,0.068/kWh, 0.065/kWh,and0.064/kWh, respectively. This study gives scope to the economic standpoints of other locations with the same population characteristics
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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