Journal Description
Clean Technologies
Clean Technologies
is an international, peer-reviewed, open access journal of scientific research on technology development aiming to reduce the environmental impact of human activities, and is published quarterly online by MDPI.
- Open Access— free for readers, with article processing charges (APC) paid by authors or their institutions.
- High Visibility: indexed within Scopus, ESCI (Web of Science), Inspec, AGRIS, RePEc, and other databases.
- Journal Rank: CiteScore - Q2 (Environmental Science (miscellaneous))
- Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 26.6 days after submission; acceptance to publication is undertaken in 3.8 days (median values for papers published in this journal in the second half of 2023).
- Recognition of Reviewers: APC discount vouchers, optional signed peer review, and reviewer names published annually in the journal.
Impact Factor:
3.8 (2022);
5-Year Impact Factor:
3.7 (2022)
Latest Articles
Advancing Sustainable Decision Making in Additive Manufacturing: A Comprehensive Review of Multi-Criteria Decision Making Approaches
Clean Technol. 2024, 6(2), 646-661; https://doi.org/10.3390/cleantechnol6020034 - 14 May 2024
Abstract
Additive manufacturing (AM) is one of the technologies of Industry 4.0 that has been contributing to the development of different manufacturing industries. The integration of sustainability concepts into additive manufacturing has been gaining attention among researchers. This integration is essential in the development
[...] Read more.
Additive manufacturing (AM) is one of the technologies of Industry 4.0 that has been contributing to the development of different manufacturing industries. The integration of sustainability concepts into additive manufacturing has been gaining attention among researchers. This integration is essential in the development of AM technologies and can be a significant asset in terms of decision making for organizations. This work aims to present a concise literature review on the integration of decision making, especially multi-criteria decision making, and sustainability into the AM environment. The literature on this topic currently possesses a total of fifteen documents, which were analyzed in this work. Some developments on this topic have been achieved in domains such as material selection, process selection and challenges, and drivers’ analysis of sustainable AM. This review shows that even though there has been an effort in recent years to integrate sustainability into additive manufacturing, there is still a long road to the development of this topic for the future, and so some recommendations for future research paths are presented.
Full article
(This article belongs to the Collection Brilliant Young Researchers in Clean Technologies)
►
Show Figures
Open AccessArticle
Water Treatment with Clean Technologies Using Moringa oleifera Seeds in Alternative Low-Cost Clarification Units
by
Jéssica R. Silva and Danieli S. Oliveira
Clean Technol. 2024, 6(2), 625-645; https://doi.org/10.3390/cleantechnol6020033 - 14 May 2024
Abstract
►▼
Show Figures
Water is an essential element for human survival, yet many individuals still lack access to treated water to meet their basic needs. To mitigate this situation, alternative water treatment technologies that are accessible and easy to handle are being explored. Among these, the
[...] Read more.
Water is an essential element for human survival, yet many individuals still lack access to treated water to meet their basic needs. To mitigate this situation, alternative water treatment technologies that are accessible and easy to handle are being explored. Among these, the use of Moringa oleifera seeds as a natural coagulant and the application of a helically coiled tube as a flocculation unit have been studied. In this context, this study aimed to evaluate the turbidity removal efficiency using two different coagulants (Moringa oleifera and aluminum sulfate) in an alternative water clarification system. The system consists of a helically coiled tube flocculator (HCTF) coupled with a conventional decantation unit. It was observed that the coagulant solution from shelled seeds required a lower dosage to achieve efficiencies above 90% compared to the coagulant solution from seeds with shells. The optimal dosage was 30 mL/L of the coagulant solution from shelled seeds. This dosage resulted in high turbidity-removal efficiencies, ranging from 92% to 100%. The processing method of the seeds that yielded the highest efficiency in turbidity removal was the mortar and pestle, as opposed to a blender. The optimal configuration of the alternative water clarification system comprised using the lower HCTF in a horizontal orientation. The use of the alternative water clarification system, along with the natural coagulant, proves to be a promising alternative clean technology for water clarification in locations without access to conventional treatment, being efficient in turbidity removal.
Full article
Figure 1
Open AccessArticle
On–off-Grid Optimal Hybrid Renewable Energy Systems for House Units in Iraq
by
Hussain Alshamri, Timothy Cockerill, Alison S. Tomlin, Moustafa Al-Damook and Mansour Al Qubeissi
Clean Technol. 2024, 6(2), 602-624; https://doi.org/10.3390/cleantechnol6020032 - 9 May 2024
Abstract
►▼
Show Figures
This paper addresses the optimal sizing of Hybrid Renewable Energy Systems (HRESs), encompassing wind, solar, and battery systems, with the aim of delivering reliable performance at a reasonable cost. The focus is on mitigating unscheduled outages on the national grid in Iraq. The
[...] Read more.
This paper addresses the optimal sizing of Hybrid Renewable Energy Systems (HRESs), encompassing wind, solar, and battery systems, with the aim of delivering reliable performance at a reasonable cost. The focus is on mitigating unscheduled outages on the national grid in Iraq. The proposed On–off-grid HRES method is implemented using MATLAB and relies on an iterative technique to achieve multi-objectives, balancing reliability and economic constraints. The optimal HRES configuration is determined by evaluating various scenarios related to energy flow management, electricity prices, and land cover effects. Consumer requirements regarding cost and reliability are factored into a 2D optimization process. A battery model is developed to capture the dynamic exchange of energy among different renewable sources, battery storage, and energy demands. A detailed case study across fifteen locations in Iraq, including water, desert, and urban areas, revealed that local wind speed significantly affects the feasibility and efficiency of the HRES. Locations with higher wind speeds, such as the Haditha lake region (payback period: 7.8 years), benefit more than urban areas (Haditha city: payback period: 12.4 years). This study also found that not utilizing the battery, particularly during periods of high electricity prices (e.g., 2015), significantly impacts the HRES performance. In the Haditha water area, for instance, this technique reduced the payback period from 20.1 to 7.8 years by reducing the frequency of charging and discharging cycles and subsequently mitigating the need for battery replacement.
Full article
Figure 1
Open AccessArticle
Tobacco Farmers’ Perceptions of Unsafe Tobacco Cultivation and Its Effect on Health and Environment: A Case of Chittagong Hill Tracts, Bangladesh
by
Niamah Atya Mim, Shaikh Shamim Hasan, Muhammad Ziaul Hoque, Minhaz Ahmed and Prabin Chakma
Clean Technol. 2024, 6(2), 586-601; https://doi.org/10.3390/cleantechnol6020031 - 8 May 2024
Abstract
As the environment is severely harmed by tobacco (like growing, processing, production, and disposal), the study was set forth to determine the tobacco cultivation status and perceptions of the tobacco farmers toward the environmental and health hazards of tobacco farmers due to tobacco
[...] Read more.
As the environment is severely harmed by tobacco (like growing, processing, production, and disposal), the study was set forth to determine the tobacco cultivation status and perceptions of the tobacco farmers toward the environmental and health hazards of tobacco farmers due to tobacco cultivation. We conducted the study in Lama Upazila, Bandarban Hill District, Bangladesh. The survey method was applied to collect the necessary data, utilizing a pre-structured interview schedule, from 242 tobacco farmers who were selected randomly. The study’s results portrayed that the average tobacco cultivation farming experience of the farmers was about 10 years, and the farmers occupied about 0.97 acres of land for cultivating tobacco, while 81% of the tobacco farmers utilized the plain lands for cultivating tobacco, although the study area was a hilly one. A huge amount of fuel wood (average 5390 kg) was required for the curing of tobacco leaves. The farmers produced about 2 MT of tobacco per year and earned about BDT 89,066 (USD 810) from this production. Given that 77% of the tobacco farmers in the research area felt that tobacco production increased the risks to the environment and tobacco farmers health, their opinions ranged from somewhat to highly favorable, which meant they were concerned about the environment and health hazards. The research’s findings provide useful background knowledge on the detrimental effects of Bangladesh’s tobacco farming.
Full article
(This article belongs to the Collection Brilliant Young Researchers in Clean Technologies)
►▼
Show Figures
Graphical abstract
Open AccessArticle
Introduction of the Experimental Setup for the Investigation of the Novel Selective Melt Dispersion (SMD): A Directed Energy Deposition (DED) Process
by
Sebastian F. Noller, Anja Pfennig and Matthias Dahlmeyer
Clean Technol. 2024, 6(2), 572-585; https://doi.org/10.3390/cleantechnol6020030 - 7 May 2024
Abstract
This study focuses on developing an experimental setup to investigate the Selective Melt Dispersion (SMD), a Directed Energy Deposition (DED) process. SMD as a means of in-process joining (IPJ) aims to integrate components and assemblies during additive manufacturing, combining the advantages of various
[...] Read more.
This study focuses on developing an experimental setup to investigate the Selective Melt Dispersion (SMD), a Directed Energy Deposition (DED) process. SMD as a means of in-process joining (IPJ) aims to integrate components and assemblies during additive manufacturing, combining the advantages of various processes for eco-friendly and economical resource utilization. The research initially analyzed DED systems and defined requirements for subsystems and the overall system. Critical subsystems, including the energy source, material feed, and others, were sequentially developed, and a proof of concept involved building 20 stacked welded tracks, validated through micrograph analysis. The study concludes by evaluating and discussing the fulfillment of the defined requirements. The system comprises a centrally arranged vibration-assisted powder feed; a laterally arranged laser incidence at a 45° angle; a kinematic structure where all axes are arranged on the workpiece, so the powder supply does not require movement; and a shield gas supply.
Full article
(This article belongs to the Topic Clean Energy Technologies and Assessment)
►▼
Show Figures
Figure 1
Open AccessArticle
Environmental Impacts Associated with the Production and Packing of Persian Lemon in Mexico through Life-Cycle Assessment
by
Eduardo Castillo-González, Lorena De Medina-Salas, Mario Rafael Giraldi-Díaz, Raúl Velásquez-De La Cruz and José Rafael Jiménez-Ochoa
Clean Technol. 2024, 6(2), 551-571; https://doi.org/10.3390/cleantechnol6020029 - 7 May 2024
Abstract
►▼
Show Figures
In this study, the environmental impacts associated with the intensive production of Persian lemons are assessed, including the agricultural and packing phases of the fresh fruit. A life-cycle assessment (LCA) tool was used in accordance with the ISO 14040 and 14044 standards and
[...] Read more.
In this study, the environmental impacts associated with the intensive production of Persian lemons are assessed, including the agricultural and packing phases of the fresh fruit. A life-cycle assessment (LCA) tool was used in accordance with the ISO 14040 and 14044 standards and implemented in SimaPro PhD (9.2) software. The life-cycle inventory database was primarily composed of data collected during field visits to local lemon orchards and the main packing company in the region. The functional unit was defined as 1 kg of packed fresh Persian lemons. The selected impact categories were the carbon footprint, water footprint, and energy footprint, and the results obtained for the defined functional unit were 405.8 g CO2 eq, 40.3 L of water, and 5.9 MJ, respectively. The industrial packing phase of the fruits had a greater impact on the carbon and energy footprints, mostly due to the manufacturing of packaging materials and cardboard boxes, followed by the transportation of supplies. Regarding the water footprint, the agricultural phase was identified as the most significant contributor to water consumption, primarily attributed to maintenance operations and the application of agrochemicals.
Full article
Figure 1
Open AccessArticle
Intelligent Control Based on Usage Habits in a Domestic Refrigerator with Variable Speed Compressor for Energy-Saving
by
Juan M. Belman-Flores, Donato Hernández-Fusilier, Juan J. García-Pabón and David A. Rodríguez-Valderrama
Clean Technol. 2024, 6(2), 528-550; https://doi.org/10.3390/cleantechnol6020028 - 30 Apr 2024
Abstract
►▼
Show Figures
Maintaining adequate temperatures for preserving food in a domestic refrigerator is a task that is affected by several factors, including the daily use of the appliance. In this sense, this work presents the development of a novel control system based on fuzzy logic
[...] Read more.
Maintaining adequate temperatures for preserving food in a domestic refrigerator is a task that is affected by several factors, including the daily use of the appliance. In this sense, this work presents the development of a novel control system based on fuzzy logic that considers usage habits such as the amount of food entering the refrigerator and the frequency of opening doors. Thus, the control comprises input variables corresponding to the internal temperatures of both compartments, the thermal load entered, and the refrigerator door-opening signal. By simulating the usage habits of a refrigerator with a variable-speed compressor, the control performance was evaluated. The results showed that implementing fuzzy control using usage habits was robust enough to maintain adequate thermal conditions within the compartments and a lower thermal fluctuation concerning the reference control of the refrigerator (factory control). In terms of energy, the fuzzy control resulted in an energy saving of 3.20% with the refrigerator empty (without thermal load) compared to the reference control. On the other hand, the individual integration of the thermal load in the fuzzy control resulted in 2.08% energy savings and 5.45% for the integration of the thermal load compared to the reference control. Finally, considering the combination of usage habits, the fuzzy control presented a higher energy consumption than the reference control, around 9.7%. In this case, the fuzzy control maintained more favorable thermal conditions in both compartments, whereas the reference control presented a warmer thermal condition in the freezer.
Full article
Figure 1
Open AccessArticle
Evaluation of Distillery Fractions in Direct Methanol Fuel Cells and Screening of Reaction Products
by
Giuseppe Montevecchi, Maria Cannio, Umberto Cancelli, Andrea Antonelli and Marcello Romagnoli
Clean Technol. 2024, 6(2), 513-527; https://doi.org/10.3390/cleantechnol6020027 - 22 Apr 2024
Abstract
Fuel cells represent an appealing avenue for harnessing eco-friendly energy. While their fuel supply traditionally stems from water electrolysis, an environmentally conscious approach also involves utilizing low-weight alcohols like methanol and ethanol. These alcohols, concentrated from sustainable sources within the enological by-product distillation
[...] Read more.
Fuel cells represent an appealing avenue for harnessing eco-friendly energy. While their fuel supply traditionally stems from water electrolysis, an environmentally conscious approach also involves utilizing low-weight alcohols like methanol and ethanol. These alcohols, concentrated from sustainable sources within the enological by-product distillation process, offer a noteworthy contribution to the circular economy. This study delved into evaluating the efficacy of distillery fractions in powering methanol fuel cells. Beyond their energy-generation potential, the performed GC-MS analysis unveiled appreciable quantities of acetic acid resulting from the partial oxidation of ethanol. This revelation opens the door to intriguing possibilities, including the recovery and repurposing of novel compounds such as short-chain fatty acids (predominantly acetic acid), ketones, and aldehydes—establishing a link between sustainable energy production and the emergence of valuable by-product applications.
Full article
(This article belongs to the Special Issue Valorization of Industrial and Agro Waste)
►▼
Show Figures
Figure 1
Open AccessArticle
Numerical Investigation for Power Generation by Microbial Fuel Cells Treating Municipal Wastewater in Guelph, Canada
by
Yiming Li and Shunde Yin
Clean Technol. 2024, 6(2), 497-512; https://doi.org/10.3390/cleantechnol6020026 - 19 Apr 2024
Abstract
►▼
Show Figures
Significant research endeavors have focused on microbial fuel cell (MFC) systems within wastewater treatment protocols owing to their unique capacity to convert chemical energy from waste into electricity while maintaining minimal nutrient concentrations in the effluent. While prior studies predominantly relied on empirical
[...] Read more.
Significant research endeavors have focused on microbial fuel cell (MFC) systems within wastewater treatment protocols owing to their unique capacity to convert chemical energy from waste into electricity while maintaining minimal nutrient concentrations in the effluent. While prior studies predominantly relied on empirical investigations, there remains a need to explore modeling and simulation approaches. Assessing MFC systems’ performance and power generation based on real wastewater data is pivotal for their practical implementation. To address this, a MATLAB model is developed to elucidate how MFC parameters and constraints influence system performance and enhance wastewater treatment efficiency. Leveraging actual wastewater data from a municipal plant in Guelph, Canada, six sets of MFC models are employed to examine the relationship between power generation and six distinct parameters (inflow velocity, membrane thickness, internal resistance, anode surface area, feed concentration, and hydraulic retention time). Based on these analyses, the final model projects a total power generation of 50,515.16 kW for the entire wastewater treatment plant in a day, capable of supporting approximately 2530 one-person households. Furthermore, the model demonstrates a notably higher chemical oxygen demand (COD) removal rate (75%) compared to the Guelph WWTP. This comprehensive model serves as a valuable tool for future simulations in similar wastewater treatment plants, providing insights for optimizing performance and aiding in practical applications.
Full article
Figure 1
Open AccessEditorial
CO2 Capture and Sequestration
by
Diganta Bhusan Das
Clean Technol. 2024, 6(2), 494-496; https://doi.org/10.3390/cleantechnol6020025 - 16 Apr 2024
Abstract
CO2 capture and sequestration (CCS) aims to capture carbon dioxide (CO2) from CO2 sources (e [...]
Full article
(This article belongs to the Special Issue CO2 Capture and Sequestration)
Open AccessArticle
Wind–PV–Battery Hybrid Off-Grid System: Control Design and Real-Time Testing
by
Miloud Rezkallah, Ambrish Chandra and Hussein Ibrahim
Clean Technol. 2024, 6(2), 471-493; https://doi.org/10.3390/cleantechnol6020024 - 15 Apr 2024
Abstract
The paper presents the design and implementation of decentralized control for a PV–wind–battery hybrid off-grid system with limited power electronics devices and sensors. To perform well without using any maximum power point tracking (MPPT) technique from the wind turbine (WT) based on a
[...] Read more.
The paper presents the design and implementation of decentralized control for a PV–wind–battery hybrid off-grid system with limited power electronics devices and sensors. To perform well without using any maximum power point tracking (MPPT) technique from the wind turbine (WT) based on a permanent-magnet brushless DC generator (PMBLDCG) and solar panels (PVs) and balance the power in the system, a cascade control structure strategy based on a linear active disturbance rejection controller (LADRC) is developed for the two-switch DC-DC buck-boost converter. Moreover, to ensure an uninterruptible power supply to the connected loads with a constant voltage and frequency, a cascade d-q control structure based on LADRC is developed for the interfacing single-phase inverter. Furthermore, the modeling and controller parameters design are presented. The performance under all operation conditions of the hybrid off-grid configuration and its decentralized control is validated by simulation using MATLAB/Simulink and in real-time using a small-scale hardware prototype.
Full article
(This article belongs to the Topic Clean Energy Technologies and Assessment)
►▼
Show Figures
Figure 1
Open AccessArticle
Biogas as Alternative to Liquefied Petroleum Gas in Mauritania: An Integrated Future Approach for Energy Sustainability and Socio-Economic Development
by
Sidahmed Sidi Habib and Shuichi Torii
Clean Technol. 2024, 6(2), 453-470; https://doi.org/10.3390/cleantechnol6020023 - 11 Apr 2024
Abstract
The global shift from conventional energy sources to sustainable alternatives has garnered significant attention, driven by the promise of economic benefits and environmental sustainability. The current study rigorously investigated the economic advantages and sustainability achieved from the transition of households in Mauritania from
[...] Read more.
The global shift from conventional energy sources to sustainable alternatives has garnered significant attention, driven by the promise of economic benefits and environmental sustainability. The current study rigorously investigated the economic advantages and sustainability achieved from the transition of households in Mauritania from liquefied petroleum gas (LPG) to biogas utilization. The study constitutes a robust case study that centers on assessing the multifaceted impacts of this transition on household finances and overall quality of life in Mauritania. This case focuses on biogas technology adoption and its role as a competitor of LPG in Mauritania. The energy poverty portfolio of the nation has been explored and livestock waste generation and biogas production potential have been estimated at 2451 million cubic meters annually. Biogas production can fulfill 50% of the energy requirement for cooking purposes within the country. The community scale fixed-dome-type biogas digesters have been recommended for Mauritania by considering a community of 100 families. The calculated payback period for the community project is 74 months, and after the payback period, continuous monthly benefits of USD 1750 will be started. Livestock manure is directly utilized for farming practices in Mauritania, which produces 10.7 Gg of methane emissions per year. Biogas production is a clean and economically viable option for Mauritania, which can also be beneficial for reducing the methane emissions footprints of the livestock sector. This case study will prove as a vital project for other African nations if successfully implemented. Multiple recommendations for the policy-makers of Mauritania have also been formulated, like tariffs on biogas production facilities and swift financing schemes, which can further strengthen the biogas production on a national scale. International funders should also take part in coping with the energy demand of Mauritania and its mission to mitigate climate change rather than utilizing LPG on a national scale. Biogas production and utilization are much cheaper compared with the fluctuating prices of LPG and ensure health when cooking.
Full article
(This article belongs to the Collection Bioenergy Technologies)
►▼
Show Figures
Figure 1
Open AccessReview
Sustainable Treatment of Spent Photovoltaic Solar Panels Using Plasma Pyrolysis Technology and Its Economic Significance
by
Ping Fa Chiang, Shanshan Han, Mugabekazi Joie Claire, Ndungutse Jean Maurice, Mohammadtaghi Vakili and Abdulmoseen Segun Giwa
Clean Technol. 2024, 6(2), 432-452; https://doi.org/10.3390/cleantechnol6020022 - 9 Apr 2024
Abstract
In the past few decades, the solar energy market has increased significantly, with an increasing number of photovoltaic (PV) modules being deployed around the world each year. Some believe that these PV modules have a lifespan of around 25–30 years. As their lifetime
[...] Read more.
In the past few decades, the solar energy market has increased significantly, with an increasing number of photovoltaic (PV) modules being deployed around the world each year. Some believe that these PV modules have a lifespan of around 25–30 years. As their lifetime is limited, solar panels wind up in the waste stream after their end of life (EoL). Several ecological challenges are associated with their inappropriate disposal due to the presence of hazardous heavy metals (HMs). Some studies have reported different treatment technologies, including pyrolysis, stabilization, physical separation, landfill, and the use of chemicals. Each proposed treatment technique pollutes the environment and underutilizes the potential resources present in discarded solar panels (DSPs). This review recommends thermal plasma pyrolysis as a promising treatment technology. This process will have significant advantages, such as preventing toxic HMs from contaminating the soil and groundwater, reducing the amount of e-waste from DSPs in an environmentally friendly and economical way, and allows the utilization of the valuable resources contained in EoL photovoltaic solar panel modules by converting them into hydrogen-rich syngas to generate thermal energy, electricity, and non-leachable slag that can be used as an additive in other treatment processes or as a conditioner to improve soil properties. However, plasma pyrolysis uses a high temperature to break down waste materials, a challenge which can be offset by the integration of this process in anaerobic digestion (AD), as the slag from plasma pyrolysis can be used as an additive in AD treatments to produce high yields of biogas and improve nutrient recovery. Moreover, the produced energy from both processes can operate the entire plant in which they take place and increase the net energy production, a resource which can be sold for an additional income. Future challenges and recommendations are also highlighted.
Full article
(This article belongs to the Collection Review Papers in Clean Technologies)
►▼
Show Figures
Figure 1
Open AccessArticle
Forecasting Pitch Response of Floating Offshore Wind Turbines with a Deep Learning Model
by
Mohammad Barooni and Deniz Velioglu Sogut
Clean Technol. 2024, 6(2), 418-431; https://doi.org/10.3390/cleantechnol6020021 - 29 Mar 2024
Abstract
The design and optimization of floating offshore wind turbines (FOWTs) pose significant challenges, stemming from the complex interplay among aerodynamics, hydrodynamics, structural dynamics, and control systems. In this context, this study introduces an innovative method for forecasting the dynamic behavior of FOWTs under
[...] Read more.
The design and optimization of floating offshore wind turbines (FOWTs) pose significant challenges, stemming from the complex interplay among aerodynamics, hydrodynamics, structural dynamics, and control systems. In this context, this study introduces an innovative method for forecasting the dynamic behavior of FOWTs under various conditions by merging Convolutional Neural Network (CNN) with a Gated Recurrent Unit (GRU) network. This model outperforms traditional numerical models by delivering precise and efficient predictions of dynamic FOWT responses. It adeptly handles computational complexities and reduces processing duration, while maintaining flexibility and effectively managing nonlinear dynamics. The model’s prowess is showcased through an analysis of a spar-type FOWT in a multivariate parallel time series dataset using the CNN–GRU structure. The outcomes are notably promising, underscoring the model’s proficiency in accurately forecasting the performance of FOWTs.
Full article
(This article belongs to the Topic Advances in Wind Energy Technology)
►▼
Show Figures
Figure 1
Open AccessArticle
Optimizing Renewable Energy Integration through Innovative Hybrid Microgrid Design: A Case Study of Najran Secondary Industrial Institute in Saudi Arabia
by
Mana Abusaq and Mohamed A. Zohdy
Clean Technol. 2024, 6(2), 397-417; https://doi.org/10.3390/cleantechnol6020020 - 25 Mar 2024
Abstract
►▼
Show Figures
Amidst a growing global focus on sustainable energy, this study investigates the underutilization of renewable resources in the southern region of Saudi Arabia, with a specific emphasis on the Najran Secondary Industrial Institute (NSII). This research presents an in-depth analysis of installing a
[...] Read more.
Amidst a growing global focus on sustainable energy, this study investigates the underutilization of renewable resources in the southern region of Saudi Arabia, with a specific emphasis on the Najran Secondary Industrial Institute (NSII). This research presents an in-depth analysis of installing a hybrid microgrid (MG) system on the roofs of NSII buildings, exploring six cases with varying tilt and azimuth angles. The study innovatively integrates architectural design and system administration, a novel approach for this location, and benchmarks the optimal angles against Hybrid Optimization of Multiple Energy Resources (HOMER) software defaults. The proposed system consists of solar photovoltaic (PV) panels, a battery storage system (BSS), a converter, a diesel generator (DG), and a grid. The selected model balances technological and economic viability with environmental considerations, ensuring a reliable power supply within the NSII’s roof area constraints. An extensive sensitivity analysis evaluates the system’s resilience across different scenarios. The current system, which is grid-only, has an estimated Net Present Cost (NPC) of about USD 7.02M and emits 1.81M kg/yr of CO2. The findings point to installing a microgrid with a 20.97° tilt and 50° azimuth angle as optimal, demonstrating 54.69% lower NPC and 92% lower CO2 emissions, along with zero kWh/year unmet electrical load when applying the resilience assessments. This outcome highlights Saudi Arabia’s southern region’s renewable energy potential, aligning with national mega-projects and energy initiatives.
Full article
Figure 1
Open AccessArticle
Design of a Solar Dish Receiver and Life Cycle Assessment of a Hot Water System
by
Ibrahim Tursunović and Davide Papurello
Clean Technol. 2024, 6(1), 379-396; https://doi.org/10.3390/cleantechnol6010019 - 19 Mar 2024
Abstract
The energy sector is the main source of greenhouse gases, so it has the highest potential for improvement. The improvements can be achieved by generating energy from renewable sources. It is necessary to combine production from renewable sources with storage systems. Thermal energy
[...] Read more.
The energy sector is the main source of greenhouse gases, so it has the highest potential for improvement. The improvements can be achieved by generating energy from renewable sources. It is necessary to combine production from renewable sources with storage systems. Thermal energy storage using concentrated solar power systems is a promising technology for dispatchable renewable energy that can guarantee a stable energy supply even in remote areas without contributing to greenhouse gas emissions during operation. However, it must be emphasised that greenhouse gases and other impacts can occur during the production process of concentrating solar system components. This paper analyses the receiver design to produce thermal energy for the existing CSP dish plant at the Energy Center of the Politecnico di Torino. The plant is designed to produce electrical energy in the spring and summer periods. In addition to this energy production, the CSP can be adopted to produce thermal energy, through hot water, during the less favourable periods of the year in terms of global solar radiation. The surface heat flux is calculated in the first part of the analysis to obtain the maximum internal temperature in the receiver, which is 873.7 °C. This value is a constraint for the choice of material for the solar receiver. A life cycle assessment is performed to compare the emissions generated during the production of the main components of the CSP system with the emissions generated by the methane-fuelled water heater to produce the same amount of thermal energy. It can be concluded that the production of the main components of the CSP system results in lower greenhouse gas emissions than the operational phase of a conventional system. Given the assumptions made, the utilization of methane leads to the emission of approximately 12,240 kg of CO2, whereas the production of the CSP system results in emissions totalling 5332.8 kg of CO2 equivalent
Full article
(This article belongs to the Collection Brilliant Young Researchers in Clean Technologies)
►▼
Show Figures
Figure 1
Open AccessReview
Status of Concentrated Solar Power Plants Installed Worldwide: Past and Present Data
by
Sylvain Rodat and Richard Thonig
Clean Technol. 2024, 6(1), 365-378; https://doi.org/10.3390/cleantechnol6010018 - 19 Mar 2024
Abstract
Solar energy is not only the most abundant energy on earth but it is also renewable. The use of this energy is expanding very rapidly mainly through photovoltaic technology. However, electricity storage remains a bottleneck in tackling solar resource variability. Thus, solar thermal
[...] Read more.
Solar energy is not only the most abundant energy on earth but it is also renewable. The use of this energy is expanding very rapidly mainly through photovoltaic technology. However, electricity storage remains a bottleneck in tackling solar resource variability. Thus, solar thermal energy becomes of particular interest when energy storage is required, as thermal energy storage is much cheaper than electricity storage. The objective of this paper is to make a short update on the CSP (Concentrated Solar Power) market as of the year 2023. It is based on the CSP-GURU database, which lists information on CSP power plants all over the world. Although this database is open, it is not easy to find UpToDate analysis. An overview of this expanding technology is presented and offers readable figures with the most important information. This includes the evolution of installed capacities worldwide along with upcoming projects (under construction) and technological trends. The evolution of storage capacities and operating temperatures is discussed. Investment costs and levelized cost of electricity are also provided to obtain reliable data for comparison with other energy technologies. Specific land requirements are highlighted, along with overall efficiency. Relevant examples are discussed in this paper. Eventually, it outlines the evolution of the CSP landscape with useful information for scientific and educational purposes.
Full article
(This article belongs to the Collection Review Papers in Clean Technologies)
►▼
Show Figures
Figure 1
Open AccessArticle
Ammonium Removal in Wastewater Treatments by Adsorbent Geopolymer Material with Granite Wastes: Full-Scale Validation
by
M. Otero, L. Freire, S. Gómez-Cuervo and C. Ávila
Clean Technol. 2024, 6(1), 339-364; https://doi.org/10.3390/cleantechnol6010017 - 7 Mar 2024
Abstract
Elevated ammonium (NH4+) concentrations in untreated waterways contribute to eutrophication and dissolved oxygen depletion. Geopolymer (GP) materials are introduced as sustainable, straightforward operation and low-cost option for pollutant adsorption through ion exchange mechanism. In the present study, a porous metakaolin-based
[...] Read more.
Elevated ammonium (NH4+) concentrations in untreated waterways contribute to eutrophication and dissolved oxygen depletion. Geopolymer (GP) materials are introduced as sustainable, straightforward operation and low-cost option for pollutant adsorption through ion exchange mechanism. In the present study, a porous metakaolin-based geopolymer with granite waste additions was synthetized, characterised and validated as adsorbent material for NH4+ pollution in water. At this point, treatments to reduce GP alkalis leaching were also considered to comply with the water discharge regulations. The adsorption mechanism was analysed by Redlich-Peterson isotherm model concluding that NH4+ was disposed on the GP surface as a monolayer with strong physical-chemical attraction between molecules. Kinetics of the process followed the Weber-Morris rate equation being the intraparticle diffusion the limiting process. Continuous experiments at lab-scale suggested a maximum removal of 97% during the first hours and an adsorption capacity (q) of 25.24 mg/g. Additionally, as a main novelty of the work, the GP was validated in a full-scale pilot plant monitoring pH, electrical conductivity and NH4+ concentration. The obtained data revealed that the GP is high selective in a real wastewater stream and removed 81% of NH4+, higher adsorption values than those reported for natural and some synthetic zeolites.
Full article
(This article belongs to the Collection Water and Wastewater Treatment Technologies)
►▼
Show Figures
Figure 1
Open AccessArticle
Reinforcement Fiber Production from Wheat Straw for Wastepaper-Based Packaging Using Steam Refining with Sodium Carbonate
by
Sebastian Hagel and Fokko Schütt
Clean Technol. 2024, 6(1), 322-338; https://doi.org/10.3390/cleantechnol6010016 - 5 Mar 2024
Abstract
Locally sourced agricultural residues are a promising feedstock for the production of reinforcement fibers for wastepaper-based packaging papers. An eco-friendly high yield process to generate fibers from wheat straw using high pressure steam and sodium carbonate is presented. The wheat straw was impregnated
[...] Read more.
Locally sourced agricultural residues are a promising feedstock for the production of reinforcement fibers for wastepaper-based packaging papers. An eco-friendly high yield process to generate fibers from wheat straw using high pressure steam and sodium carbonate is presented. The wheat straw was impregnated with up to 16% of sodium carbonate and steam treated for 10 min at temperatures from 148 °C to 203 °C. The pulps were characterized concerning their chemical composition and test sheets with 100% straw fibers and with 15% and 30% straw fibers blended with recycled pulp were prepared. Fiber yields ranged from 70% to 45%, wherein more severe treatment conditions contributed to increased paper strength but lower yields. At comparable fiber yields, treatments featuring a higher chemical input, coupled with lower treatment temperatures, resulted in improved paper strength. By blending recycled pulp with up to 30% of straw fibers with a beating degree of roughly 45 °SR, the burst, compression and tensile strength was enhanced by up to 66%, 74% and 59%, respectively. As the enhancement effect decreases with a high steam treatment intensity and a high proportion of wheat straw, a moderate treatment and limited use of wheat straw may be the best choice.
Full article
(This article belongs to the Special Issue Valorization of Industrial and Agro Waste)
►▼
Show Figures
Figure 1
Open AccessReview
Superhydrophobic Materials from Waste: Innovative Approach
by
Maria Cannio, Dino Norberto Boccaccini, Stefano Caporali and Rosa Taurino
Clean Technol. 2024, 6(1), 299-321; https://doi.org/10.3390/cleantechnol6010015 - 4 Mar 2024
Abstract
Superhydrophobic materials, known for their exceptional water-repellent properties, have found widespread applications in diverse fields such as self-cleaning surfaces, anti-icing coatings, and water-resistant textiles. In recent years, researchers have explored a sustainable approach by repurposing waste materials to create superhydrophobic surfaces. This eco-friendly
[...] Read more.
Superhydrophobic materials, known for their exceptional water-repellent properties, have found widespread applications in diverse fields such as self-cleaning surfaces, anti-icing coatings, and water-resistant textiles. In recent years, researchers have explored a sustainable approach by repurposing waste materials to create superhydrophobic surfaces. This eco-friendly approach not only reduces environmental impact but also aligns with circular economy principles, contributing to a more sustainable future. Creating superhydrophobic materials from waste involves a combination of surface modification techniques and hierarchical structuring, with rigorous characterization to ensure the desired properties. These materials showcase their potential in various industries, opening doors to more environmentally friendly technologies. This review delves into the concept of superhydrophobic materials derived from waste and the methods used for their synthesis. It begins by defining superhydrophobicity and highlighting its unique characteristics. It emphasizes the pivotal role played by superhydrophobic materials across industries. The review then explores waste materials’ untapped potential, discussing the advantages of harnessing waste for superhydrophobic material development. Concrete examples of promising waste materials are provided, including agricultural residues and industrial byproducts. The review outlines five key sections that will be further developed to offer a comprehensive understanding of this innovative and sustainable approach to superhydrophobic materials.
Full article
(This article belongs to the Special Issue Valorization of Industrial and Agro Waste)
►▼
Show Figures
Graphical abstract
Highly Accessed Articles
Latest Books
E-Mail Alert
News
Topics
Topic in
Clean Technol., Energies, Environments, Processes, Sustainability
Sustainable Energy: Efficient Technological Solutions Combining Environmental, Economic, Political and Social Aspects
Topic Editors: Fabio Orecchini, Adriano Santiangeli, Fabrizio ZuccariDeadline: 15 June 2024
Topic in
Buildings, Clean Technol., Materials, Recycling, Sustainability
Circular Economy Innovations and Breakthroughs for Built Environments
Topic Editors: Sakdirat Kaewunruen, Katerina Tsikaloudaki, Ruben P. Borg, Yunlong GuoDeadline: 31 August 2024
Topic in
Clean Technol., Environments, Pollutants, Sustainability, Toxics
New Advances in Adsorptive and Extractive Methods for Pollutant Removal
Topic Editors: Rui Wang, Xinpeng Liu, Yunqian Ma, Kai ZhangDeadline: 29 September 2024
Topic in
Clean Technol., Energies, Materials, Solar, Sustainability
Smart Solar Energy Systems
Topic Editors: Venizelos Efthymiou, Minas PatsalidesDeadline: 15 November 2024
Conferences
Special Issues
Special Issue in
Clean Technol.
Simulations of Photovoltaic and Thermophotovoltaic Solar Cells—Transport and Optics
Guest Editor: Atilla Ozgur CakmakDeadline: 31 May 2024
Special Issue in
Clean Technol.
Decentralised Water Treatment Technologies
Guest Editors: Diganta Bhusan Das, Kashyap Kumar Dubey, Lipika DekaDeadline: 30 June 2024
Special Issue in
Clean Technol.
Environmental Engineering Perspectives on Waste Management, Nature-Based Solutions (NbS) and Green/Blue Infrastructure
Guest Editors: Joseph Akunna, Kiran Tota-MaharajDeadline: 31 July 2024
Special Issue in
Clean Technol.
Thermal Storage Power Plants (TSPP)
Guest Editor: Franz TriebDeadline: 31 August 2024
Topical Collections
Topical Collection in
Clean Technol.
Brilliant Young Researchers in Clean Technologies
Collection Editor: Patricia Luis Alconero
Topical Collection in
Clean Technol.
Water and Wastewater Treatment Technologies
Collection Editor: Susana Rodriguez-Couto
Topical Collection in
Clean Technol.
Clean Catalytic Technologies
Collection Editor: Dmitry Yu. Murzin