https://ejournal.undip.ac.id/index.php/ijred/issue/feedInternational Journal of Renewable Energy Development2023-11-15T10:52:06+00:00Editorial Officeijred@live.undip.ac.idOpen Journal Systems<p><strong><img style="border: 10px solid white;" src="/public/site/images/hadiyanto001/December,_2023_21.png" alt="" width="170" height="220" align="left" />The International Journal of Renewable Energy Development - (<em>Int. J. Renew. Energy Dev.</em>; p-ISSN: 2252-4940; e-ISSN:<span>2716-4519, CODEN: <span>IJREAC, OCLC: <span>830327507; LC: <span>2014252655</span></span>)</span> </span></strong>is an open access and peer-reviewed journal co-published by Center of Biomass and Renewable Energy (CBIORE) that aims to promote renewable energy researches and developments, and it provides a link between scientists, engineers, economist, societies and other practitioners. The International Journal of Renewable Energy Development has been identified in crossref with a prefix DOI number: 10.14710/ijred.</p><p><strong>International Journal of Renewable Energy Development</strong> is currently being <span style="text-decoration: underline;"><strong>indexed</strong></span> in <a href="https://www.scopus.com/sourceid/21100905391?origin=resultslist">Scopus</a> database and <span>has a listing and ranking in the </span><a href="https://www.scimagojr.com/journalsearch.php?q=21100905391&tip=sid&clean=0">SJR (SCImago Journal and Country Rank)</a>, ESCI (Clarivate Analytics), CNKI Scholar as well as accredited in <strong>SINTA 1 (First grade category journal)</strong> by The Directorate General of Higher Education, The Ministry of Education, Culture, Research and Technology, The Republic of Indonesia under a decree No 200/M/KPT/2020.</p><p>The scope of journal encompasses: Photovoltaic technology, Solar thermal applications, Biomass and Bioenergy, Wind energy technology, Material science and technology, Low energy architecture, Geothermal energy, Wave and tidal energy, Hydro power, Hydrogen production technology, Energy policy, Socio-economic on energy, Energy efficiency, planning and management, Life cycle assessment. </p><p><span>The journal also welcomes papers on other related topics provided that such topics are within the context of the broader multi-disciplinary scope of developments of r</span>enewable energy<span>. </span></p>https://ejournal.undip.ac.id/index.php/ijred/article/view/53928Theoretical study of a double-slope solar still with solar air heater condenser2023-11-15T10:51:06+00:00Ahmed Ghazyahmed.ghazy@usask.ca<p>Despite their limited water production and efficiency, double-slope solar stills are an appropriate solution for water scarcity in hot arid regions. Numerous studies have focused on enhancing the effectiveness of double-slope solar stills. In this context, this study introduces a double-slope solar with a solar air heater condenser (DSSS-SAHC). The back cover of a conventional double-slope solar still was replaced by a glass air heater in order to recover the still’s thermal losses in heating air. The transient performance of the DSSS-SAHC was investigated numerically under real weather conditions and compared to the performance of a conventional double-slope solar still (CDSSS) with the same aspects. The impact of various weather and operation factors on the DSSS-SAHC performance was investigated at air flows of 0.01 and 0.1 kg/s to account for both natural and forced air circulation, respectively. The results revealed an increase of about 15% and 6% in the thermal efficiency of the DSSS-SAHC over that of the CDSSS, respectively, at air flows of 0.1 and 0.01 kg/s despite the DSSS-SAHC distillate was insignificantly greater than that of the CDSSS at both air flows. In addition, the water distillate of the DSSS-SAHC increased as the solar irradiance increased, the ambient wind and ambient temperature had contrary effects on the efficiency, and the initial saline water level had a negligible impact on the overall performance</p>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/54072Performance analysis of hybrid PV-diesel-storage system in AGRS-Hassi R’mel Algeria2023-11-15T10:51:06+00:00Ahssen Mahmoudiahssen_m@yahoo.comAmina Manel Bouazizbouazizaminamanel@gmail.comMohamed Najib Bouazizmn_bouaziz@email.comDjohra Saheb-Koussadkoussa@cder.dz<div><p>The main research paper focuses on the optimal hybrid system using HOMER software in the central plant of Hassi R’mel. Indeed, the system is composed of PV panels, a battery bank, and a diesel engine, all of which are used to supply an industrial load. Hence, the present work proposes a solution to optimize the power generated by the power sources, maximize the photovoltaic source use, and minimize the use of the battery bank and the diesel generator. Moreover, the solution aims to guarantee the safe operation of the system components and continuity in the load power supply. These objectives are performed by the minimization of a cost function, in which the power generation cost, the energetic balance, and the environmental parameters are taken into consideration. Among the five solutions, the most optimal system obtained is PV/Diesel/batteries /Grid. This system consists of 1200 KW PV, an 1100 KW diesel generator, 800 units of battery, and an 1100 KW converter. Therefore, to supply the station with 49% of electricity by PV and 51% by diesel while the reduction of emissions is 60%, and 708020 liters of diesel is saved. Applying the sensitivity analysis also showed that renewable resources have an impact on the sizing of PV. When solar radiation increases, the size of renewable energy decreases and the NPC decreases as well. It can, thus, be illustrated that the PV/diesel/battery system is not fully-optimal. This strategy is recommended for industrial system security since it can be used to ensure systems from an energetic and economic point of view.<strong></strong></p></div><br /><p> </p>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/56569Long-term performance of roof-top GCPV systems in central Viet Nam2023-11-15T10:51:06+00:00Thi Hong Nguyennthong@hueic.edu.vnQuoc Vuong Dangvuong.dangquoc@hust.edu.vnXuan Cuong Ngongoxuancuong@hueuni.edu.vnNhu Y Dodonhuy@humg.edu.vn<div><p>In pursuit of the objective of achieving "net zero emissions," many countries worldwide, including Viet Nam, have prioritized the utilization of photovoltaic technology for energy conversion. Specifically, the implementation of roof-top grid-connected photovoltaic systems (GCPV) has emerged as a highly efficient solution in urban areas. These systems offer several advantages, such as minimizing land usage, lowering monthly electricity expenses, preventing building heat, generating income for households, and reducing transmission and distribution costs. This article focuses on a comprehensive long-term analysis conducted on 51 roof-top GCPV systems in the tropical monsoon climate of Hue City, Viet Nam, during the period from 2019 to 2023. The analysis findings reveal that roof-top GCPV systems with a capacity of 3-6 kW are well-suited for households in the central region of Viet Nam, characterized by a tropical monsoon climate. These systems exhibit an average sizing ratio of 1.03. The annual average daily final yield peaked at 3.28 kWh/kWp/day in 2021 and reached its lowest point at 2.97 kWh/kWp/day in 2022. Notably, the typical slope of the yield gradually increases with the installed capacity and the studied year. Furthermore, the monthly average daily final yield demonstrates a seasonal pattern, with higher yields observed from March to August and lower yields from September to January, aligning with the climate of the study area. As the years progress, the capacity factor and performance ratio of roof-top GCPV systems display a declining trend. Throughout the entire study period, these systems successfully mitigated 664 metric tons of CO2 emissions. The evaluation of long-term yield data offers valuable insights for photovoltaic installers, operators, and system owners, aiding in system maintenance and optimizing load utilization across different time periods. Long-term performance can be used by energy managers and owners of roof-top GCPV systems to identify supply shortfalls and initiate countermeasures.</p></div>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/57601Assessing the energy efficiency of fossil fuel in ASEAN2023-11-15T10:51:06+00:00Sharifah Aishah Syed Aliaishah@upnm.edu.myAhmad Shafiq Abdul Rahmanahmadshafiq@upnm.edu.myMuhamad Fathul Naim Mohamadfathuln212@gmail.comLatifah Sarah Supiansarah@upnm.edu.myHaliza Mohd Zaharihaliza.mz@upnm.edu.myMohd Norsyarizad Razalinorsyarizad@upnm.edu.my<div><p>The world's industries, transportation systems, and households rely heavily on fossil fuels despite their limited availability and high carbon content. Therefore, it is of the utmost importance to improve fossil fuel energy efficiency in order to facilitate the shift towards a sustainable energy system with reduced greenhouse gas emissions. This paper employs a slacks-based measure network data envelopment analysis model with undesirable outputs to assess the efficiencies of fossil fuel energy in the Association of Southeast Asian Nations (ASEAN) countries during a span of seven years, specifically from 2015 to 2021. The inclusion of undesirable outputs in this study is important because it allows for a more realistic assessment of efficiency by considering factors like CO<sub>2</sub> emissions, which are undesirable outcomes associated with fossil fuel use. The datasets utilised in this study are sourced from the U.S. Energy Information Administration and the open data website of Our World in Data. Based on the findings, it can be observed that Singapore and the Philippines have demonstrated outstanding performance in maximising the utilisation of fossil fuels. In contrast, Myanmar exhibits the lowest level of efficiency in this analysis. By identifying top-performing countries in terms of fossil fuel efficiency, it is possible to implement measures to boost efficiency in under-performing countries. This can be achieved through the promotion and adoption of cleaner energy alternatives, specifically renewable energy sources that exhibit a low or negligible carbon footprint. These findings offer significant contributions to policymakers exploring sustainable energy usage, environmental stewardship, and the formulation and execution of comprehensive strategies that aim to mitigate carbon dioxide emissions arising from the consumption of fossil fuels in the ASEAN region.</p></div>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/56575Effect of the non-uniform combustion core shape on the biochar production characteristics of the household biomass gasifier stove2023-11-15T10:51:06+00:00Somchet Chaiyalapsomchettana2519@gmail.comRitthikrai Chai-ngamritthikrai.c@msu.ac.thJuthaporn Saengprajakjuthaporn.s@msu.ac.thJenjira Piamdeejenjira@msu.ac.thApipong Putkhamapipong.p@msu.ac.thArnusorn Saengprajakarnusorn.s@msu.ac.th<p>The global demand for biochar in agricultural and carbon sequestration applications is increasing; nevertheless, biochar production using the 50-liter household biomass gasifier stove (50L-HBGS) in Thailand found major issues that need to be improved. The objective of this study was to study the effects of the airflow in the non-uniform combustion core shape (NCCS) on the biochar production characteristic of the 50L-HBGS. The new design of the NCCS was constructed and studied to replace the existing combustion core shape (ECCS) at Mahasarakham University. The height, air inlet, and air outlet diameters of the NCCS were designed at 45, 24, and 11.4 cm, respectively. The NCCS with 21 holes of the pyrolysis gas outlet, a diameter of 4 mm for each, was integrated into the 50L-HBGS and performed comparative tests to the ECCS using 9 kg of bamboo wood chunks in three consecutive experiments. The airflow and the combustion behavior were studied through the stove temperature profiles, which were recorded every 5 minutes using a digital data logger. The biochar products were studied using the scanning electron microscope (SEM) with the energy dispersive x-ray spectroscopy (EDS), Fourier transform infrared spectroscopy (FTIR), and the proximate analysis technique. The study indicated that the 50L-HBGS with the NCCS made significantly improved the airflow rates in the combustion core, resulting in better continuous burning during the ignition state than with the ECCS. Moreover, the pyrolysis temperatures were significantly improved, it was provided temperatures during the pyrolysis process reached higher than 500 <sup>o</sup>C, resulting in the liquid tar being removed and no unburned wood chunks remaining at the end. The characterization result demonstrated that the 50L-HBGS with the NCCS had created biochar within a range of micropore and macrospore sizes and high fixed carbon content, which could be advantageously used for different agricultural and carbon sequestration applications.</p>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/58035Assessing the feasibility of gray, blue, and green ammonia productions in Indonesia: A techno-economic and environmental perspective2023-11-15T10:51:06+00:00Martin Tjahjonomartin.tjahjono@calvin.ac.idIsabella Stevanistevani@gmail.comGracheilla A Siswantosiswanto@gmail.comArief Adhityaadhitya@gmail.comIskandar Halimiskandarhalim@gmail.com<div><p>Ammonia, owing to its carbon-free attributes, stands as a promising alternative for replacing fossil-based fuels. This study investigates the techno-economic and environmental aspects of gray, blue, and green ammonia production in Indonesia. In this regard, a spreadsheet-based decision support system has been developed to analyze the levelized cost of each mode of ammonia production and their cost sensitivity across various parameters. The results of the analysis show a levelized cost of gray ammonia of $297 (USD) per ton, which is strongly affected by natural gas prices and carbon taxation. Blue ammonia emerges as the most stable production option with a levelized cost of $390 per ton, impacted by natural gas prices and the expenses associated with carbon sequestration. On the other hand, the levelized cost of green ammonia varies between $696 to $1,024 per ton and is predominantly influenced by the choice of electrolyzers, the cost of renewable energy sources, and maintenance and operational expenditures. Furthermore, the study reveals that gray and blue ammonia production result in emissions of 2.73 and 0.28 tons of CO<sub>2</sub> equivalent per ton of ammonia, respectively, while in-situ carbon emissions from green ammonia can be considered negligible. Overall, this study underscores the potential of implementing green ammonia production utilizing geothermal or hydropower renewable energy resources as viable solutions for decarbonizing the power, industry, and transport sectors in Indonesia. Several policy recommendations aimed at overcoming existing barriers to the development of green ammonia plants in the country are also provided.</p></div>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/52563Unlocking Africa’s solar and wind energy potential: A panel data analysis on the determinants of the production of electricity through solar and wind energy2023-11-15T10:51:06+00:00Martina Gintarė de Vriesmg.vries95@gmail.com<p>With growing global concerns about and attention drawn to climate change, there is a pressing need to transition towards sustainable practices to live more harmoniously with the environment. To mitigate future climate changes, many support and pursue the uptake of renewable energy to slowly shift to a more electricity powered world. Africa, richly endowed with the potential of solar and wind, stands at a pivotal point with the opportunity to develop through electricity generated by renewable. Therefore, this research delves into the complexity of 25 factors influencing the production of solar and wind-powered electricity within the continent. Through a panel data analysis conducted for the years of 2010 till 2019, the study identifies several determinants to have positive and negative effects. Results highlight the intertwined nature of regional challenges and opportunities, emphasizing that political stability, socio-economic dynamics, sound national strategies, and environmental and international commitments play pivotal roles in determining the trajectory of solar and wind energy integration in Africa’s electricity mix. Notably the study underscores that a uniform approach across Africa is insufficient, instead tailored national and foreign strategies based on regional specifics found within this study are imperative for maximizing renewable energy adoption. </p>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/56172Effect of natural dye combination and pH extraction on the performance of dye-sensitized photovoltaics solar cell2023-11-15T10:51:06+00:00Indri Wasa EstiningtyasEstiningtyas@gmail.comNita Kusumawatinitakusumawati@unesa.ac.idPirim Setiarsosetiarso@gmail.comSupari Muslimmulsim@gmail.comNunik Tri Rahayurahayu@gmail.comRiska Nur Safitrisafitri@gmail.comNafisatus Zakiyahzakiyah@gmail.comFadlurachman Faizal Fachrirakarsiefaizal@gmail.com<div><p>Dyes are significant components in Dye Sensitized Solar Cell (DSSC) performance because they act as photosensitizers. Natural dye-based DSSC system fabrication innovations continue to be produced in an effort to improve DSSC performance efficiency. In this study, a DSSC system was developed using double components of natural dyes as natural photosensitizers to enhance DSSC efficiency. This method of making natural dye-based DSSC uses a combination of dye extracts from two different dye sources that have the potential as natural photosensitizers in DSSC. The research aims to investigate the impact of the combined use of two natural dyes and pH variations on DSSC performance. DSSC performance measurements encompass the short-circuit current (Isc), open-circuit voltage (Voc), and DSSC efficiency parameters. The obtained results indicate efficiency values for dyes (a) sappan wood/ethanol and turmeric/methanol; (b) turmeric/methanol and beetroot/ethanol; and (c) beetroot/ethanol and turmeric/distilled water. At neutral pH, the efficiency values are 2.09%, 2.10%, and 2.19%, respectively. Meanwhile, at acidic pH of 2.59%; 2.39%; and 2.71%. Notably, the dye efficiency values at acidic pH surpass those found at neutral pH conditions. The highest efficiency is observed in the combination of dye (c) beetroot/ethanol and turmeric/distilled water with efficiency reaching 2.71% at acidic pH.</p></div>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/56907The feasibility of utilizing microwave-assisted pyrolysis for Albizia branches biomass conversion into biofuel productions2023-11-15T10:51:06+00:00Maha Faisal Abdmaha.abd2107m@coeng.uobaghdad.edu.iqAtheer Mohammed Al-YaqoobiAl-yaqoobi@gmail.com<div><p>The consumption of fossil fuels has caused many challenges, including environmental and climate damage, global warming, and rising energy costs, which has prompted seeking to substitute other alternative sources. The current study explored the microwave pyrolysis of <em>Albizia branches</em> to assess its potential to produce all forms of fuel (solid, liquid, gas), time savings, and effective thermal heat transfer. The impact of the critical parameters on the quantity and quality of the biofuel generation, including time, power levels, biomass weight, and particle size, were investigated. The results revealed that the best bio-oil production was 76% at a power level of 450 W and 20 g of biomass. Additionally, low power levels led to enhanced biochar production, where a percentage of 70% appeared when employing a power level of 300 W. Higher power levels were used to increase the creation of gaseous fuels in all circumstances, such as in 700 W, the gas yield was 31%. The density, viscosity, acidity, HHV, GC-MS, and FTIR instruments were used to analyze the physical and chemical characteristics of the bio-oil. The GC-MS analysis showed that the bio-oil consists of aromatic compounds, ketones, aldehydes, acids, esters, alkane, alkenes and heterocyclic compounds. The most prevalent component was aromatic compounds with 12.79% and ketones with 12.15%, while the pH of the oil obtained was 5, and the HHV was 19.5 MJ/kg. The pyrolysis productions could be promising raw materials for different applications after further processing.</p></div>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/58218HOMER optimization of standalone PV/Wind/Battery powered hydrogen refueling stations located at twenty selected French cities2023-11-15T10:51:06+00:00Fakher Oueslatifakher.oueslati@gmail.com<div><p>The current study proposes a model of autonomous Hydrogen Refuelling Stations (HRFS) installed on different sites in twenty French cities powered by renewable clean energy sources. The station is fully powered by photovoltaic (PV) panels, wind turbines with battery storage and involving an electrolyzer and hydrogen tank for producing and storing hydrogen. Using Homer simulation, three scenarios are investigated to propose an optimized model, namely Scenario 1 containing (PV-Wind-Battery) system, Scenario 2 with (Wind-Battery) technologies and Scenario 3 with (PV-Battery) components. The otimization process executed demonstrates very competitive levelized cost of energy (LCOE) and levelized cost of hydrogen (LCOH) especially for the third scenario solely based on PV power with LCOE in range $0.354-0.435/kWh and a LCOH varying within $13.5-16.5/kg, for all 20 cities. An average net present cost (NPC) value of $ 1,561,429 and $ 2,522,727 are predicted for the first and second architectures while least net present cost of $1,038,117 is estimated for the third combination solely based on solar power according to all sites considered. For instance, minimum values are obtained for Marseille city with LCOE=$ 0.354/kWh and a LCOH=$ 13.5 /kg in conformity with the minimum obtained value of NPC value of $886,464 with respect to the winner third scenario. In addition, more costly hydrogen production is expected for Grenoble city especially for scenario 1 and 2 where wind turbine technology is introduced. On another hand, thorough analysis of PV/wind hydrogen techno-economic operation is provided including improvements recommendations, scenarios comparison and environmental impact discussion.</p></div>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/56035The effect of aeration rate and feedstock density on biodrying performance for wet refuse-derived fuel quality improvement2023-11-15T10:51:06+00:00Tanik Itsarathorntanikits@scg.comSirintornthep Towprayoonsirin.jgsee@gmail.comChart Chiemchaisrifengccc@ku.ac.thSuthum Patumsawadsuthum.p@eng.kmutnb.ac.thAwassada Phongphiphatawassada@outlook.comAbhisit Bhatsadaabhisit.bh@hotmail.comKomsilp Wangyaokomsilp@gmail.com<div><p>This study investigates the effect of aeration rate and feedstock density on the biodrying process to improve the quality of type 2 wet refuse-derived fuel. The aeration rate and feedstock density were varied to investigate these parameters’ effect on the system’s performance. The experiments used 0.3 m<sup>3 </sup>lysimeters with continuous negative ventilation and five days of operation. In Experiment A, aeration rates of 0.4, 0.5, and 0.6 m<sup>3</sup>/kg/day were tested with a feedstock bulk density of 232 kg/m<sup>3</sup>. In Experiment B, the optimum aeration rates determined in Experiment A (0.5 and 0.6 m<sup>3</sup>/kg/day) were used, and the feedstock density was varied (232 kg/m<sup>3</sup>, 250 kg/m<sup>3</sup>, and 270 kg/m<sup>3</sup>). The results showed that an aeration rate of 0.5 m<sup>3</sup>/kg/day was the most efficient for a feedstock density of 232 kg/m<sup>3</sup>; when the aeration rate was increased to 0.6 m<sup>3</sup>/kg/day, a feedstock density of 250 kg/m<sup>3</sup> was the most effective. However, a feedstock density of 270 kg/m<sup>3</sup> was not found to be practical for use in the quality improvement system. When the feedstock density is increased, the water in the feedstock and the water resulting from the biodegradation process cannot evaporate due to the feedstock layer’s low porosity, and the system requires an increased aeration rate. Furthermore, the increase in density scaled with increased initial volatile solid content, initial organic content, and initial moisture content, which significantly impacted the final moisture content based on multivariate regression analysis.</p></div>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/57902Photovoltaic power prediction based on sky images and tokens-to-token vision transformer2023-11-15T10:51:06+00:00Qiangsheng Daiday_qs@163.comXuesong Huohuoxuesong@js.sgcc.com.cnDawei Sudavid_su@js.sgcc.com.cnZhiwei Cui690059695@qq.com<div><p>Photovoltaic (PV) power generation has high uncertainties due to the randomness and imbalance nature of solar energy and meteorological parameters. Hence, accurate PV power forecasts are essential in the operation of PV power plants (PVPP) for short-term dispatches and power generation schedules. In this paper, a new deep neural network structure based on vision transformer is proposed to combine sky images and Tokens-To-Token(T2T) for photovoltaic power prediction. The method uses an incremental tokenization module to aggregate neighboring image patches into tokens, which capture the local structural information of the clouds. Then, an efficient T2T-ViT backbone network is used to extract the global attentional relationships of the tokens for power prediction. In order to evaluate the performance of the proposed model, the method was compared with several deep learning architectures such as ResNet and GoogleNet on a dataset collected by the National Renewable Energy Laboratory in Colorado, USA. The results of power prediction were analysed using training loss, prediction error, and linear regression, and they show that the proposed method achieves higher prediction accuracy and lower error compared to the existing methods, especially in short- and ultra-short-term prediction. The paper demonstrates the potential of applying Transformer models to computer vision tasks for renewable energy forecasting. The results show that the proposed method achieves higher prediction accuracy and lower error than several deep learning architectures, such as ResNet and GoogleNet, especially in short- and ultra-short-term prediction.</p></div>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/58228Evaluating the role of operating temperature and residence time in the torrefaction of betel nutshells for solid fuel production2023-11-15T10:51:06+00:00Pongpathai KitrungloadjanapornKitrungloadjanaporn@gmail.comLe Quang Sangle@gmail.comJirasak Pukdumpukdum@gmail.comTinnapob Phengpomtinnapob.phe@mahidol.ac.th<p>This research addresses the urgent need for sustainable bioenergy alternatives, specifically evaluating betel nutshells as potential replacements for conventional biomass materials like coconut and palm fibers. The objective of the study was to gauge the inherent bioenergy potential of betel nutshells through an investigation of torrefaction under varying conditions, specifically temperatures ranging from 200-300 °C and residence times between 20-60 minutes in an inert environment. In this study, proximate analyses were utilized to investigate essential characteristics including moisture content, volatile matter, ash content, and fixed carbon, while a bomb calorimeter was used to determine their higher heating values. Initial results indicated that untreated betel nutshells had higher heating values and compositional similarities to coconut and palm fibers, highlighting their potential as a bioenergy source. Advanced torrefaction processes, involving increased temperatures and extended residence times, raised the fixed carbon content and reduced moisture in betel nutshells, thereby optimizing their higher heating value. This improvement is attributed to the decomposition of covalent bonds in the biomass structures, leading to the release of volatile compounds and consequent reductions in both oxygen-to-carbon and hydrogen-to-carbon ratios. Remarkably, at an operating temperature of 300 °C and a residence time of 60 minutes, torrefied betel nutshells reached a higher heating value of 25.20 MJ/kg, marking a substantial 31.39 % increase compared to untreated specimens. This study conclusively positions betel nutshells, typically considered agricultural waste, as competitive alternatives to traditional biomass resources in the biofuel industry.</p>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/57327Experimental investigation on the performance of a pyramid solar still for varying water depth, contaminated water temperature, and addition of circular fins2023-11-15T10:51:06+00:00Mayilsamy Yuvaperiyasamyyuvaperiyasamyvsb@gmail.comNatarajan Senthilkumarnskmfg@gmail.comBalakrishnan Deepanrajbabudeepan@gmail.com<p><span lang="IN">The experimental investigation was meant to investigate the effect of water depth in the basin, the water temperature at the inlet of solar still, and adding circular fins to the pyramid solar still on freshwater output. The investigation was divided into three sections. The first area of research is to study effect of increasing water depth in the solar still, which ranged from 2 to 6 cm, second section concentrated on varying the inflow water temperature from 30 to 50ºC, and third section investigated the influence of incorporating circular fins into the solar still basin on the water output and quality. The experimental findings showed that basin depth considerably impacts freshwater flow. The highest significant difference, 38%, was recorded by changing the water level in the basin from 2 to 6 cm. Freshwater yielded the most at a depth of 2 cm, totalling 1250.3 mL, followed by 1046 mL at a depth of 3 cm. A water depth of 4 cm produced 999 mL, whereas a water depth of 5 cm made 911 mL. The lowest production occurred at a water depth of 6 cm, producing 732 mL; furthermore, including fins at the bottom increased productivity by 8.2%. Elevating the temperature from 30 to 50ºC of the inlet water led to a water output increase of 15.3% to 22.2%. These findings underscore the profound potential of harnessing solar energy to address global water challenges and pave the way for further advancements in efficient freshwater production</span></p>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/57800Improving FTO/ZnO/In2S3/CuInS2/Mo solar cell efficiency by optimizing thickness and carrier concentrations of ZnO, In2S3 and CuInS2 thin films using Silvaco-Atlas Software2023-11-15T10:51:06+00:00Maklewa Agoundedembaamaklewa@gmail.comMazabalo Banetobaneto@gmail.comRaphael Nyengenyenge@gmail.comNicholas Musilamusila@gmail.comKicoun Jean-Yves N'Zi Touretoure@gmail.com<div><p>Optimization of optical and electrical properties of active semiconducting layers is required to enhance thin film solar cells' efficiency and consequently became the cornerstone for sustainable energy production. Computational studies are one of the ways forward to optimize solar cells’ characteristics. In this study, Silvaco-Atlas, a powerful software that excels in both 2D and 3D electrical simulations of semiconductors has been used for the simulation in order to investigate the solar cell properties. The architecture of the solar cell simulated was FTO/ZnO/In<sub>2</sub>S<sub>3</sub>/CuInS<sub>2</sub>/Mo. This study aims to optimize solar cell efficiency by optimizing film thicknesses and carrier concentrations via simulation. The designed solar cell was exposed to the presence of a sun spectrum of AM1.5 from a 1kW/m<sup>2</sup> incident power density at 300K. The thickness values of the window (ZnO), absorber (CuInS<sub>2</sub>) and buffer (In<sub>2</sub>S<sub>3</sub>) layers were varied to record a solar cell's optimum thickness. The resulting FTO/ZnO/In<sub>2</sub>S<sub>3</sub>/CuInS<sub>2</sub>/Mo solar cell formed by simulation is presented. The best efficiency and fill factor of the solar cell simulated were found to be 41.67% and 89.19%, respectively. The recorded values of current density and the open circuit voltage of the cell were 40.33mA/cm<sup>2</sup> and 1.15 V, respectively. Additionally, the maximum power of the simulated solar cell device was 41.68 mW. Optimization results revealed that the most efficient cell found was made up of a window layer with a thickness of 0.03μm, an absorber layer with a thickness of 6.0μm and a buffer layer with a thickness of 0.2μm. The optimized carrier concentration of ZnO, In<sub>2</sub>S<sub>3</sub> and CuInS<sub>2</sub> was respectively 1e21 cm<sup>-3</sup>, 1e20 cm<sup>-3</sup>, 3e18 cm<sup>-3</sup> and the optimized Al-doped ZnO value was 1e25 cm<sup>-3</sup>. The Absorption spectra indicated that the solar cell's peak absorption occurs between 350 nm and 1250 nm and presented a good external quantum efficiency (EQE) of around 84.52% to 92.83% which indicates good efficiency in the visible domain. This performance is attributed to the transparency of FTO, ZnO and good absorption of In<sub>2</sub>S<sub>3</sub> and CuInS<sub>2</sub> thin films.</p></div>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/57805Transition metal-based materials and their catalytic influence on MgH2 hydrogen storage: A review2023-11-15T10:51:06+00:00Oluwashina Philips Gbeneborphilipsogbenebor@gmail.comAbimbola Patricia Idowu Popoolapopoola@gmail.com<p>The dependence on fossil fuels for energy has culminated in its gradual depletion and this has generated the need to seek alternative source that will be environmentally friendly and sustainable. Hydrogen stands to be promising in this regard as energy carrier which has been proven to be efficient. Magnesium hydride (MgH<sub>2</sub>) can be used in storing hydrogen because of its availability, light weight and low cost. In this review, monoatomic, alloy, intermetallic and composite forms of Ti, Ni, V, Mo, Fe, Cr, Co, Zr and Nb as additives on MgH<sub>2</sub> are discussed. Through ball milling, additive reacts with MgH<sub>2</sub> to form compounds including TiH<sub>2</sub>, Mg<sub>2</sub>Ni, Mg<sub>2</sub>NiH<sub>4</sub>, V<sub>2</sub>O, VH<sub>2</sub>, MoSe, Mg<sub>2</sub>FeH<sub>6</sub>, NbH and Nb<sub>2</sub>O<sub>5</sub>which remain stable after certain de/hydrogenation cycles. Some monoatomic transition metals remain unreacted even after de/hydrogenation cycles. These formed compounds, including stable monoatomic transition metals, impart their catalytic effects by creating diffusion channels for hydrogen via weakening Mg - H bond strength. This reduces hydrogen de/sorption temperatures, activation energies and in turn, hastens hydrogen desorption kinetics of MgH<sub>2</sub>. Hydrogen storage output of MgH<sub>2</sub>/transition metal-based materials depend on additive type, ratio of MgH<sub>2</sub>/additive, ball milling time, ball –to combining materials ratio and de/hydrogenation cycle. There is a need for more investigations to be carried out on nanostructured binary and ternary transition metal-based materials as additives to enhance the hydrogen storage performance of MgH<sub>2</sub>. In addition, the already established compounds (listed above) formed after ball milling or dehydrogenation can be processed and directly doped into MgH<sub>2</sub>. </p>2023-11-01T00:00:00+00:00Copyright (c) 2023 The Author(s). Published by Centre of Biomass and Renewable Energy (CBIORE)https://ejournal.undip.ac.id/index.php/ijred/article/view/57139Retraction Notice to Control of Bidirectional DC-DC Converter for Micro-Energy Grid’s DC Feeders' Power Flow Application, IJRED 11(2), 533-5462023-11-15T10:52:06+00:00H Hadiyantohady.hadiyanto@gmail.com<div class="referenced-article-title"><strong>Refers to: </strong></div><div class="referenced-article-title"><strong><br /></strong></div><div class="refers-to-content"><div class="u-clamp-2-lines"><a title="RETRACTED: Control of Bidirectional DC-DC Converter for Micro-Energy Grid’s DC Feeders' Power Flow Application" href="https://doi.org/10.14710/ijred.2022.41952">RETRACTED: <span>Control of Bidirectional DC-DC Converter for Micro-Energy Grid’s DC Feeders' Power Flow Application</span></a>.</div><div class="u-clr-grey6"> </div><div class="u-clr-grey6">International Journal of Renewable Energy Development, Volume 11(2), May 2022, Pages 533-546</div><div class="u-margin-xs-bottom"> </div><div class="u-margin-xs-bottom">Muhammad Hammad Saeed, Wang Fangzong, Basheer Ahmed Kalwar</div></div><p> -------------------------------------------------------------------------------------------------------------------------------</p><p> </p>2023-11-01T00:00:00+00:00Copyright (c) 2023