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Energy for Sustainable Future

A special issue of Energies (ISSN 1996-1073). This special issue belongs to the section "B: Energy and Environment".

Deadline for manuscript submissions: closed (31 March 2021) | Viewed by 37927

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Special Issue Editors

Special Issue Information

Dear Colleagues,

Energy and the environment are interrelated to one another, and they are one of the important factors that influence the development of societies. The pollution of the environment without taking into account various consequences has become one of the most important global issues today. This environmental pollution is mainly the result of increases in economic activities, population, transportation, electricity generation, agriculture, forestry, and land use. The exigency of energy for these activities, the rapidly rising price of petroleum oil, the deleterious effect of greenhouse gases, and the quest for energy security have steered our attention towards sustainable sources of energy. It is fundamental to find innovative solutions that are sustainable from the perspective of energy management and environmental protection technologies. This will provide a promising future in terms of energy sources meeting energy demand, together with maintaining the environment. This Special Issue solicits original research articles as well as critical review articles that cover relevant up-to-date topics related to energy and environmental technologies which have become established ways of thinking, unifying the various methodologies. This “Energy for Sustainable Future” Special Issue in Energies is dedicated to sharing ideas in the area of energy and environment and advancing knowledge among practitioners, scientists, researchers, policymakers, and professionals to nurture innovative ideas required to solve problems in energy and environment for a sustainable future.

Prof. Dr. T M Indra Mahlia
Dr. Islam Md Rizwanul Fattah
Guest Editors

Manuscript Submission Information

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Keywords

  • sustainable energy technologies
  • bioenergy and biofuels
  • energy and environmental impact
  • nanotechnology for Green Energy and the environment
  • waste to energy
  • energy efficiency in the built environment
  • adoption of clean energy and energy security
  • CO2 capture and storage
  • energy policy and economics
  • air pollution policy

Published Papers (12 papers)

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Editorial

Jump to: Research, Review

2 pages, 148 KiB  
Editorial
Energy for Sustainable Future
by T. M. Indra Mahlia and I. M. Rizwanul Fattah
Energies 2021, 14(23), 7962; https://doi.org/10.3390/en14237962 - 29 Nov 2021
Viewed by 1206
Abstract
Energy and the environment are interrelated, and they are critical factors that influence the development of societies [...] Full article
(This article belongs to the Special Issue Energy for Sustainable Future)

Research

Jump to: Editorial, Review

17 pages, 1303 KiB  
Article
On Approaching Relevant Cost-Effective Sustainable Maintenance of Mineral Oil-Filled Electrical Transformers
by Ramsey Jadim, Mirka Kans, Jesko Schulte, Mohammed Alhattab, May Alhendi and Ali Bushehry
Energies 2021, 14(12), 3670; https://doi.org/10.3390/en14123670 - 20 Jun 2021
Cited by 4 | Viewed by 2212
Abstract
Fire and explosion accidents of oil-filled electrical transformers are leading to negative impacts, not only on the delivery of energy, but also on workplace health and safety as well as the surrounding environment. Such accidents are still being reported, regardless of applying the [...] Read more.
Fire and explosion accidents of oil-filled electrical transformers are leading to negative impacts, not only on the delivery of energy, but also on workplace health and safety as well as the surrounding environment. Such accidents are still being reported, regardless of applying the regular maintenance strategy in the power plants. The purpose of this paper is to integrate a sustainability perspective into the maintenance strategy. The problem addressed is: how can we approach the relevant cost-effective sustainable maintenance for oil-filled electrical transformers? For this purpose, an empirical study in a power plant in Kuwait was introduced. The first stage was to carry out a sustainability assessment using the ABCD procedure. In this procedure, gaps to approach sustainability were identified and actions prioritized to close these gaps were demonstrated. Applying this procedure yielded an early fault diagnosis (EFD) model for achieving cost-effective sustainable maintenance using a fault trend chart based on a novel numerical method. Implementing this model resulted in an extension of the lifetime of transformers with suspected failure propagation, leading to a deferral of the replacement investment costs. The principal conclusion of this paper is the importance of viewing the maintenance strategy of transformers from a strategic sustainability perspective, in order to approach relevant cost-effective sustainable maintenance. Full article
(This article belongs to the Special Issue Energy for Sustainable Future)
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19 pages, 562 KiB  
Article
Stakeholders’ Recount on the Dynamics of Indonesia’s Renewable Energy Sector
by Satya Widya Yudha, Benny Tjahjono and Philip Longhurst
Energies 2021, 14(10), 2762; https://doi.org/10.3390/en14102762 - 12 May 2021
Cited by 6 | Viewed by 2765
Abstract
The study described in this paper uses direct evidence from processes applied for the developing economy of Indonesia, as it defines the trajectory for its future energy policy and energy research agenda. The paper addresses the research gap to make explicit the process [...] Read more.
The study described in this paper uses direct evidence from processes applied for the developing economy of Indonesia, as it defines the trajectory for its future energy policy and energy research agenda. The paper addresses the research gap to make explicit the process undertaken by key stakeholders in assessing and determining the suitability, feasibility, and dynamics of the renewable energy sector. Barriers and enablers that are key in selecting the most suitable renewable energy sources for developing economies for the renewable energy development have been identified from extensive analyses of research documents alongside qualitative data from the Focus Group Discussions (FGD). The selected FGD participants encompass the collective views that cut across the political, economic, social, technological, legal, and environmental aspects of renewable energy development in Indonesia. The information gained from the FGD gives insights into the outlook and challenges that are central to energy transition within the country, alongside the perceptions of renewable energy development from the influential stakeholders contributing to the process. It is notable that the biggest barriers to transition are centred on planning and implementation aspects, as it is also evident that many in the community do not adhere to the same vision. Full article
(This article belongs to the Special Issue Energy for Sustainable Future)
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12 pages, 2024 KiB  
Article
Case Study of Pollution with Particulate Matter in Selected Locations of Polish Cities
by Remigiusz Jasiński, Marta Galant-Gołębiewska, Mateusz Nowak, Monika Ginter, Paula Kurzawska, Karolina Kurtyka and Marta Maciejewska
Energies 2021, 14(9), 2529; https://doi.org/10.3390/en14092529 - 28 Apr 2021
Cited by 8 | Viewed by 3148
Abstract
Despite the introduction of increasingly restrictive regulations, the air quality in Poland is still considered one of the worst in Europe. Two cities (Wroclaw and Cracow) were selected for this study, so they represent a pair of Polish cities with poor air quality, [...] Read more.
Despite the introduction of increasingly restrictive regulations, the air quality in Poland is still considered one of the worst in Europe. Two cities (Wroclaw and Cracow) were selected for this study, so they represent a pair of Polish cities with poor air quality, and at the same time are academic cities, popular with tourists. The article focuses on the emission of particulate matter, which is one of the most dangerous components of air pollution. The focus was on particles less than 10 µm in diameter which are most often neglected at measuring stations. We have identified the sources of particulate emissions in selected locations in Wroclaw and Cracow, and then measured particles in terms of their mass and number distribution. It was noted that the PM10 emission values obtained as a result of the measurements were different from the value specified by the Inspectorate of the Environmental Protection in Poland. Full article
(This article belongs to the Special Issue Energy for Sustainable Future)
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23 pages, 3673 KiB  
Article
Weather-Driven Scenario Analysis for Decommissioning Coal Power Plants in High PV Penetration Grids
by Samuel Matthew G. Dumlao and Keiichi N. Ishihara
Energies 2021, 14(9), 2389; https://doi.org/10.3390/en14092389 - 22 Apr 2021
Cited by 3 | Viewed by 2448
Abstract
Despite coal being one of the major contributors of CO2, it remains a cheap and stable source of electricity. However, several countries have turned to solar energy in their goal to “green” their energy generation. Solar energy has the potential to [...] Read more.
Despite coal being one of the major contributors of CO2, it remains a cheap and stable source of electricity. However, several countries have turned to solar energy in their goal to “green” their energy generation. Solar energy has the potential to displace coal with support from natural gas. In this study, an hourly power flow analysis was conducted to understand the potential, limitations, and implications of using solar energy as a driver for decommissioning coal power plants. To ensure the results’ robustness, the study presents a straightforward weather-driven scenario analysis that utilizes historical weather and electricity demand to generate representative scenarios. This approach was tested in Japan’s southernmost region, since it represents a regional grid with high PV penetration and a fleet of coal plants older than 40 years. The results revealed that solar power could decommission 3.5 GW of the 7 GW coal capacity in Kyushu. It was discovered that beyond 12 GW, solar power could not reduce the minimum coal capacity, but it could still reduce coal generation. By increasing the solar capacity from 10 GW to 20 GW and the LNG quota from 10 TWh to 28 TWh, solar and LNG electricty generation could reduce the emissions by 37%, but the cost will increase by 5.6%. Results also show various ways to reduce emissions, making the balance between cost and CO2 a policy decision. The results emphasized that investing in solar power alone will not be enough, and another source of energy is necessary, especially for summer and winter. The weather-driven approach highlighted the importance of weather in the analysis, as it affected the results to varying degrees. The approach, with minor changes, could easily be replicated in other nations or regions provided that historical hourly temperature, irradiance, and demand data are available. Full article
(This article belongs to the Special Issue Energy for Sustainable Future)
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17 pages, 2765 KiB  
Article
Modeling and Optimization of Microwave-Based Bio-Jet Fuel from Coconut Oil: Investigation of Response Surface Methodology (RSM) and Artificial Neural Network Methodology (ANN)
by Mei Yin Ong, Saifuddin Nomanbhay, Fitranto Kusumo, Raja Mohamad Hafriz Raja Shahruzzaman and Abd Halim Shamsuddin
Energies 2021, 14(2), 295; https://doi.org/10.3390/en14020295 - 07 Jan 2021
Cited by 21 | Viewed by 2780
Abstract
In this study, coconut oils have been transesterified with ethanol using microwave technology. The product obtained (biodiesel and FAEE) was then fractional distillated under vacuum to collect bio-kerosene or bio-jet fuel, which is a renewable fuel to operate a gas turbine engine. This [...] Read more.
In this study, coconut oils have been transesterified with ethanol using microwave technology. The product obtained (biodiesel and FAEE) was then fractional distillated under vacuum to collect bio-kerosene or bio-jet fuel, which is a renewable fuel to operate a gas turbine engine. This process was modeled using RSM and ANN for optimization purposes. The developed models were proved to be reliable and accurate through different statistical tests and the results showed that ANN modeling was better than RSM. Based on the study, the optimum bio-jet fuel production yield of 74.45 wt% could be achieved with an ethanol–oil molar ratio of 9.25:1 under microwave irradiation with a power of 163.69 W for 12.66 min. This predicted value was obtained from the ANN model that has been optimized with ACO. Besides that, the sensitivity analysis indicated that microwave power offers a dominant impact on the results, followed by the reaction time and lastly ethanol–oil molar ratio. The properties of the bio-jet fuel obtained in this work was also measured and compared with American Society for Testing and Materials (ASTM) D1655 standard. Full article
(This article belongs to the Special Issue Energy for Sustainable Future)
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24 pages, 2162 KiB  
Article
The Energy Lock-In Effect of Solar Home Systems: A Case Study in Rural Nigeria
by Olumide Hassan, Stephen Morse and Matthew Leach
Energies 2020, 13(24), 6682; https://doi.org/10.3390/en13246682 - 17 Dec 2020
Cited by 6 | Viewed by 2084
Abstract
Ongoing reductions in the costs of solar PV and battery technologies have contributed to an increased use of home energy systems in Sub-Saharan African regions without grid access. However, such systems can normally support only low-power end uses, and there has been little [...] Read more.
Ongoing reductions in the costs of solar PV and battery technologies have contributed to an increased use of home energy systems in Sub-Saharan African regions without grid access. However, such systems can normally support only low-power end uses, and there has been little research regarding the impact on households unable to transition to higher-wattage energy services in the continued absence of the grid. This paper examines the challenges facing rural energy transitions and whether households feel they are energy ‘locked in’. A mixed-methods approach using questionnaire-based household energy surveys of rural solar home system (SHS) users was used to collect qualitative and quantitative data. Thematic analysis and a mixture of descriptive and inferential statistical analyses were applied. The results showed that a significant number of households possessed appliances that could not be powered by their SHS and were willing to spend large sums to connect were a higher-capacity option available. This implied that a significant number of the households were locked into a low-energy future. Swarm electrification technology and energy efficient, DC-powered plug-and-play appliances were suggested as means to move the households to higher tiers of electricity access. Full article
(This article belongs to the Special Issue Energy for Sustainable Future)
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20 pages, 4250 KiB  
Article
Mathematical Modelling and Operational Analysis of Combined Vertical–Horizontal Heat Exchanger for Shallow Geothermal Energy Application in Cooling Mode
by Sarwo Edhy Sofyan, Eric Hu, Andrei Kotousov, Teuku Meurah Indra Riayatsyah and Razali Thaib
Energies 2020, 13(24), 6598; https://doi.org/10.3390/en13246598 - 14 Dec 2020
Cited by 4 | Viewed by 2449
Abstract
Geothermal heat exchangers (GHEs) represent a buried pipe system, which can be utilised to harness renewable thermal energy stored in the ground to improve the efficiency of heating and cooling systems. Two basic arrangements of GHEs have been widely used: vertical and horizontal. [...] Read more.
Geothermal heat exchangers (GHEs) represent a buried pipe system, which can be utilised to harness renewable thermal energy stored in the ground to improve the efficiency of heating and cooling systems. Two basic arrangements of GHEs have been widely used: vertical and horizontal. Vertical GHEs generally have a better performance in comparison with the horizontal arrangement, and these systems are particularly suitable for confined spaces. Nevertheless, the main technical challenge associated with GHEs, for either the vertical or the horizontal arrangement, is the performance deterioration associated with an increase in the operation times during summer or winter seasons. In this paper, a combined horizontal-vertical GHE arrangement is proposed to address the current challenges. The combined GHE arrangement can be operated in five different modes, corresponding to different thermal loading conditions. These five operation modes of the combined GHE are analysed based on the transient finite difference models previously developed for the horizontal and vertical arrangements. The simulation results reveal that for the single operation mode (horizontal or vertical only), the vertical GHE performs better than the horizontal GHE due to relatively stable ground temperature deep down. While, for the combined operation mode, the series operations (horizontal to vertical or vertical to horizontal) of the GHE are superior to the split mode. It is found that the effect of the fluid mass flow rate ratio is trivial on the heat dissipation of the split mode GHE. The highest heat transfer rate in the split flow operational mode is rendered by the ratio of the mass flow rate of 40% horizontal and 60% vertical. In addition, the climate condition has more effect on GHE’s performance and the increase of the fluid flow rate it can enhance the amount of energy released by the GHE. Full article
(This article belongs to the Special Issue Energy for Sustainable Future)
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13 pages, 4913 KiB  
Article
Catalyst Characteristics and Performance of Silica-Supported Zinc for Hydrodeoxygenation of Phenol
by Hamed Pourzolfaghar, Faisal Abnisa, Wan Mohd Ashri Wan Daud, Mohamed Kheireddine Aroua and Teuku Meurah Indra Mahlia
Energies 2020, 13(11), 2802; https://doi.org/10.3390/en13112802 - 01 Jun 2020
Cited by 3 | Viewed by 2230
Abstract
The present investigation aimed to study the physicochemical characteristics of supported catalysts comprising various percentages of zinc dispersed over SiO2. The physiochemical properties of these catalysts were surveyed by N2 physisorption (BET), thermogravimetry analysis (TGA), H2 temperature-programmed reduction, field-emission [...] Read more.
The present investigation aimed to study the physicochemical characteristics of supported catalysts comprising various percentages of zinc dispersed over SiO2. The physiochemical properties of these catalysts were surveyed by N2 physisorption (BET), thermogravimetry analysis (TGA), H2 temperature-programmed reduction, field-emission scanning electron microscopy (FESEM), inductively coupled plasma-optical emission spectrometry (ICP-OES), and NH3 temperature-programmed desorption (NH3-TPD). In addition, to examine the activity and performance of the catalysts for the hydrodeoxygenation (HDO) of the bio-oil oxygenated compounds, the experimental reaction runs, as well as stability and durability tests, were performed using 3% Zn/SiO2 as the catalyst. Characterization of silica-supported zinc catalysts revealed an even dispersion of the active site over the support in the various dopings of the zinc. The acidity of the calcinated catalysts elevated clearly up to 0.481 mmol/g. Moreover, characteristic outcomes indicate that elevating the doping of zinc metal led to interaction and substitution of proton sites on the SiO2 surface that finally resulted in an increase in the desorption temperature peak. The experiments were performed at temperature 500 °C, pressure 1 atm; weight hourly space velocity (WHSV) 0.32 (h−1); feed flow rate 0.5 (mL/min); and hydrogen flow rate 150 (mL/min). Based on the results, it was revealed that among all the prepared catalysts, that with 3% of zinc had the highest conversion efficiency up to 80%. However, the selectivity of the major products, analyzed by gas chromatography flame-ionization detection (GC-FID), was not influenced by the variation in the active site doping. Full article
(This article belongs to the Special Issue Energy for Sustainable Future)
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Review

Jump to: Editorial, Research

18 pages, 2868 KiB  
Review
A Review on the Thermochemical Recycling of Waste Tyres to Oil for Automobile Engine Application
by Mohammad I. Jahirul, Farhad M. Hossain, Mohammad G. Rasul and Ashfaque Ahmed Chowdhury
Energies 2021, 14(13), 3837; https://doi.org/10.3390/en14133837 - 25 Jun 2021
Cited by 25 | Viewed by 3559
Abstract
Utilising pyrolysis as a waste tyre processing technology has various economic and social advantages, along with the fact that it is an effective conversion method. Despite extensive research and a notable likelihood of success, this technology has not yet seen implementation in industrial [...] Read more.
Utilising pyrolysis as a waste tyre processing technology has various economic and social advantages, along with the fact that it is an effective conversion method. Despite extensive research and a notable likelihood of success, this technology has not yet seen implementation in industrial and commercial settings. In this review, over 100 recent publications are reviewed and summarised to give attention to the current state of global tyre waste management, pyrolysis technology, and plastic waste conversion into liquid fuel. The study also investigated the suitability of pyrolysis oil for use in diesel engines and provided the results on diesel engine performance and emission characteristics. Most studies show that discarded tyres can yield 40–60% liquid oil with a calorific value of more than 40 MJ/kg, indicating that they are appropriate for direct use as boiler and furnace fuel. It has a low cetane index, as well as high viscosity, density, and aromatic content. According to diesel engine performance and emission studies, the power output and combustion efficiency of tyre pyrolysis oil are equivalent to diesel fuel, but engine emissions (NOX, CO, CO, SOX, and HC) are significantly greater in most circumstances. These findings indicate that tyre pyrolysis oil is not suitable for direct use in commercial automobile engines, but it can be utilised as a fuel additive or combined with other fuels. Full article
(This article belongs to the Special Issue Energy for Sustainable Future)
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32 pages, 3252 KiB  
Review
A Comprehensive Review on the Recent Development of Ammonia as a Renewable Energy Carrier
by Muhammad Heikal Hasan, Teuku Meurah Indra Mahlia, M. Mofijur, I.M. Rizwanul Fattah, Fitri Handayani, Hwai Chyuan Ong and A. S. Silitonga
Energies 2021, 14(13), 3732; https://doi.org/10.3390/en14133732 - 22 Jun 2021
Cited by 49 | Viewed by 7765
Abstract
Global energy sources are being transformed from hydrocarbon-based energy sources to renewable and carbon-free energy sources such as wind, solar and hydrogen. The biggest challenge with hydrogen as a renewable energy carrier is the storage and delivery system’s complexity. Therefore, other media such [...] Read more.
Global energy sources are being transformed from hydrocarbon-based energy sources to renewable and carbon-free energy sources such as wind, solar and hydrogen. The biggest challenge with hydrogen as a renewable energy carrier is the storage and delivery system’s complexity. Therefore, other media such as ammonia for indirect storage are now being considered. Research has shown that at reasonable pressures, ammonia is easily contained as a liquid. In this form, energy density is approximately half of that of gasoline and ten times more than batteries. Ammonia can provide effective storage of renewable energy through its existing storage and distribution network. In this article, we aimed to analyse the previous studies and the current research on the preparation of ammonia as a next-generation renewable energy carrier. The study focuses on technical advances emerging in ammonia synthesis technologies, such as photocatalysis, electrocatalysis and plasmacatalysis. Ammonia is now also strongly regarded as fuel in the transport, industrial and power sectors and is relatively more versatile in reducing CO2 emissions. Therefore, the utilisation of ammonia as a renewable energy carrier plays a significant role in reducing GHG emissions. Finally, the simplicity of ammonia processing, transport and use makes it an appealing choice for the link between the development of renewable energy and demand. Full article
(This article belongs to the Special Issue Energy for Sustainable Future)
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17 pages, 643 KiB  
Review
Barriers and Solutions for Increasing the Integration of Solar Photovoltaic in Kenya’s Electricity Mix
by Dominic Samoita, Charles Nzila, Poul Alberg Østergaard and Arne Remmen
Energies 2020, 13(20), 5502; https://doi.org/10.3390/en13205502 - 20 Oct 2020
Cited by 12 | Viewed by 3667
Abstract
Currently, Kenya depends mainly on oil, geothermal energy and hydro resources for electricity production, however all three have associated issues. Oil-based electricity generation is environmentally harmful, expensive and a burden to the national trade balance. The rivers for hydropower and their tributaries are [...] Read more.
Currently, Kenya depends mainly on oil, geothermal energy and hydro resources for electricity production, however all three have associated issues. Oil-based electricity generation is environmentally harmful, expensive and a burden to the national trade balance. The rivers for hydropower and their tributaries are found in arid and semi-arid areas with erratic rainfall leading to problems of supply security, and geothermal exploitation has cost and risk issues amongst others. Given these problems and the fact that Kenya has a significant yet underexploited potential for photo voltaic (PV)-based power generation, the limited—although growing—exploitation of solar PV in Kenya is explored in this paper as a means of diversifying and stabilising electricity supply. The potential for integration of PV into the Kenyan electricity generation mix is analysed together with the sociotechnical, economic, political, and institutional and policy barriers, which limit PV integration. We argue that these barriers can be overcome with improved and more robust policy regulations, additional investments in research and development, and improved coordination of the use of different renewable energy sources. Most noticeably, storage solutions and other elements of flexibility need to be incorporated to balance the intermittent character of electricity generation based on solar PV. Full article
(This article belongs to the Special Issue Energy for Sustainable Future)
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