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The transition to low‐carbon energy and energy independence of a country play an important role in the sustainable development of its energy sector. Another important issue of sustainable energy development is the cost competitiveness in the generation process; with new renewable energy technologies, a sustainable energy transition to carbon‐neutral society is possible. In this article, we present a view of sustainable energy transformation based on a case study of Malta. We have created a simulation of a Maltese electricity system with projected growth and dominance of photovoltaic energy in the electricity market. The study results suggest that a system with a high penetration of photovoltaics has significant advantage over a conventional system using fossil fuels. In particular, in the simulated Maltese system, the total annual cost of energy was reduced threefold, the CO2 emissions were reduced by 40%, and the energy independence of Malta increased by 60%. In the end, the article gives a recommendation for further research into the Maltese energy system. [ABSTRACT FROM AUTHOR]

Malta faces a significant challenge in reducing carbon emissions, with energy consumption in its 153,100 occupied residences contributing to 30% of CO2 emissions. This study focuses on a sample of an 1870s, 80 sq-m footprint, three-story residence, emblematic of similar properties facing marketability issues due to age, structure, and maintenance. The objective is to assess a techno-economic energy and CO2 abatement framework, including advanced lighting devices, appliances, photovoltaics, wind turbines, energy storage, and vehicle-to-grid possibilities. The research evaluates comfortability and calculates potential 25-year kWh reduction and cost savings for each measure. The findings demonstrate the feasibility of implementing diversified renewable and alternative energy sources in such residences. Over 25 years, approximately 250 MWh of energy could be mitigated, leading to a reduction of approximately 140 metric tons of carbon dioxide. The study emphasizes the importance of housing stock efficiency in both new construction and retrofitting, focusing on building performance for health, comfort, and living standards. While most systems are viable, further research is needed for system-wide strategy implementation, particularly in areas like energy storage and wind turbine solutions. The study concludes that adopting emerging technologies could be advantageous in minimizing system costs through innovative building-integrated designs. [ABSTRACT FROM AUTHOR]

A high penetration of electric vehicle (EV) charging in low voltage (LV) networks can challenge grid stability due to voltage variations and limited feeder capacity. This research paper examines the integration of electric vehicle (EV) charging in real-life residential low voltage (LV) networks in Malta. The study utilizes smart metering data and presents a methodology framework and tools to analyze the impacts of EV charging on grid stability. The likelihood of challenges in the LV network is assessed by conducting simulations and deriving cumulative distribution functions (CDFs). The study also evaluates the impact of EV charging on the occurrence of network challenges and identifies predominant issues through multi-feeder analyses. Additionally, a regression analysis tool is developed to predict the impacts based on feeder characteristics. The results show strong relationships between feeder characteristics and EV charging processes, offering valuable insights for network planning and operations. However, it should be noted that the current EV charging penetration in the Maltese grid is below 1% in any LV feeder, suggesting the absence of significant technological hurdles at present. [ABSTRACT FROM AUTHOR]

High Photovoltaic (PV) and Electric Vehicle (EV) Charging Penetration challenges the grid's Low-Voltage (LV) Distribution Network's stability due to voltage variations and the overloading of feeders. This research paper investigates the potential of combined PV and Electric Vehicle (EV) charging integration within LV DN, using a representative DN in Malta as a case study. The European Union (EU) has set forth objectives and guidelines that suggest a high likelihood of Distributed Networks (DNs) incorporating a significant number of Photovoltaic Systems (PVs), resulting in overvoltage occurrences, as well as a substantial number of Electric Vehicles (EVs), which may charge in an erratic manner, leading to undervoltage and overloading events. A distribution network (DN) may experience unfavorable situations concurrently due to the simultaneous occurrence of photovoltaic (PV) generation and electric vehicle (EV) charging, particularly in residential case studies. Effectively employing either dispersed or centralized storage is a viable approach to tackle these issues. However, this strategy may defer the requirement for expensive DN investments. The study showcases the extent of automated mitigation attained in the urban zones of Malta. The data presented primarily comprises empirical measurements obtained at the onset of the LV feeder. [ABSTRACT FROM AUTHOR]

To reduce pollution and energy consumption, particularly in the automotive industry, energy saving is the main concern, and hence, Electric vehicles (EVs) are getting significantly more attention than vehicles with internal combustion engines (IC engines). Electric motors used in Electric Vehicles (EVs) must have high efficiency for maximum utilization of the energy from the batteries or fuel cells. Also, these motors must be compact, lightweight, less expensive and very easily recycled. Further, to obtain better dynamic performance, various motor control strategies are used to control the speed of the motor. And to have increased reliability, sensorless speed control techniques that offer sufficiently high performance are used. The sensorless speed control techniques are largely divided into three groups: state observer methods, indirect measurement methods and saliency-based methods. Generally, the state observer uses back emf or flux linkage to estimate the speed of the motor. Since the back emf is directly proportional to the rotor speed, at low-speed back emf based method will give poor performance. The current-based Model Reference Adaptive System (MRAS) model is also popular for estimating low speed; however, assessments deteriorate during high performance applications such as EV. This paper presents an artificial neural network (ANN)-deployed sensorless speed control of permanent magnet synchronous motor (PMSM) drive used in EVs. In this paper, the estimation of speed using the current-based MRAS model is discussed and compared with the proposed ANN-based controller, which shows significant improvement in the performance of EV motor drives. The MATLAB simulation and experimental results are presented to validate the proposed algorithm. [ABSTRACT FROM AUTHOR]

The use of a polymer composite material in electric vehicles (EVs) has been extensively investigated, especially as a substitute for steel. The key objective of this manuscript is to provide an overview of the existing and emerging technologies related to the application of such a composite, especially for battery pack applications, in which its high strength-to-weight ratio, corrosion resistance, design flexibility, and durability are advantageous compared to any metal in general. This study explores the key considerations in the design and fabrication of composites, including base material selection, structural design optimization, reinforcement material, manufacturing processes, and integration with battery systems. The paper also discusses the performance characteristics of composite battery pack structures, such as mechanical properties, thermal management, safety aspects, and environmental sustainability. This study aims to contribute to sharpening the direction of future research and innovations in the area of composite battery pack technology. [ABSTRACT FROM AUTHOR]

The paper presents the results of research on the selection of material for molds intended for geopolymer castings as well as an appropriate technological process for the preparation of such castings. Three silicons with different elasticity and hardness of 30, 40 and 60Sh were tested. The above-mentioned rubbers were used to make one-piece open molds and test the performance of each material. A model having several details and a small flat surface was chosen for the replica. Based on this variation in the wall structure, it was possible to assess the accuracy of mapping, both small elements and straight cast planes. In the prepared forms 10 tests of geopolymer casting were carried out to develop the best technological process. The appropriate result was achieved when the molds covered with the divider were flooded with raw material by vibrating them on a vibrating table, and then allowed to react for an hour for free mass components and leaking gases to the surface. After a set time, the compaction was carried out again to more accurately eliminate the resulting air bubbles. The effect of this method is to obtain a cast with precisely mapped details and a smooth even surface, and almost complete elimination of air bubbles from representative surfaces.

A circular economy is the answer to the problem of wasting raw materials and increasing environmental pollution. It is based on the effective use of materials - from extraction, through use, to the way of managing waste. Analyzing the impact of particular industries on the production of pollution, it can be concluded that the construction is one of such industries. In order to reduce the negative impact of the construction on the environment resulting from energy consumption and large amounts of generated waste, various researches are carried out on modern and innovative materials production solutions. One of the possibilities is a production technology based on the alkaline-activated compositions and geopolymers. The advantage of this technology is that it has a much lower carbon footprint compared to the traditional production methods used in construction - during the synthesis of geopolymers the emission of CO2 is 4-8 times lower and also the energy consumption is reduced up to 2-3 times. This article shows the possibility of using the industrial and mining waste for creating new eco-friendly materials – geopolymers. The paper presents the results of studies on geopolymer composites reinforced with addition of 1% by weight of different types of natural fibers i.e.: short hemp fibres, raw flax fibres (shortened), long flax fibres (stannous) and linseed cotonin. The paper showed that geopolymer composites can be successfully produced with the addition of natural fibres (often waste) and have good strength parameters even after long-term use.

This paper presents a power quality analysis for multiple electric vehicle charging stations of the AC-Level 2 type in a real-life case study. The data was collected with a power quality analyzer that measured the main distribution system feeding nine 7 kW charging stations in a commercial site with light-duty vehicles in Malta, Europe. The relevance of this study to the specific case of Malta is accentuated by the topological challenges of the country; high density of road vehicles, with 18,000 vehicles for each square kilometer; and ambitious targets of reaching carbon neutrality by 2050. Data were collected over six days on an actual charging system with real-life charging patterns. Various results are presented in this paper, including three-phase system voltages and currents, individual harmonic voltage and current components, total harmonic distortion and total current demand distortion. These measurements were compared with standardized thresholds for low-voltage equipment used in public spaces, mainly as stated in IEEE 519-2014. [ABSTRACT FROM AUTHOR]

The rapid increase in the penetration of photovoltaic (PV) power plants results in an increased risk of grid failure, primarily due to the intermittent nature of the plant. To overcome this problem, the flexible power point tracking (FPPT) algorithm has been proposed in the literature over the maximum power point tracking (MPPT) algorithm. These algorithms regulate the PV power to a certain value instead of continuously monitoring the maximum power point (MPP). The proposed work carries out a detailed comparative study of various constant power generation (CPG) control strategies. The control strategies are categorized in terms of current-, voltage-, and power-based tracking capabilities. The comparative analysis of various reported CPG/FPPT techniques was carried out. This analysis was based on some key performance indices, such as the type of control strategy, irradiance pattern, variation in G, region of operation, speed of tracking, steady-state power oscillations, drift severity scenario, partial shading scenario, implementation complexity, stability, fast dynamic response, robustness, reactive power, cost, and tracking efficiency. Among existing FPPT algorithms, model-based control has a superior performance in terms of tracking speed and low steady-state power oscillations, with a maximum tracking efficiency of 98.57%. [ABSTRACT FROM AUTHOR]

Cooling energy consumption is a major contributor to various sectors in hot climates with a significant number of warm days throughout the year. Buildings account for 40% of total energy consumption, with approximately ∼30–40% of that used for cooling in geographical areas such as Iran. Energy demand for cooling is an important factor in the overall energy efficiency of electric mobility. Electric vehicles (EVs) consume ∼30–50% of energy for the air conditioning (AC) system. Therefore, the efficient management of the cooling demand is essential in implementing energy-saving strategies. Passive radiative cooling is capable of providing subambient cooling without consuming any energy. This article reviews potential applications of passive radiative cooling in reducing cooling energy for buildings. It also provides a rough estimate of the amount of energy saved when applying a radiative cool roof to a model building. It is shown that by using radiative cool materials on roofs, the share of electricity usage for cooling can be reduced to 10%, leading to a reduction in cooling load by 90%. Additionally, the potential use of radiative cool coats of various types for different EV components, such as shell/body, windows, and fabrics, is introduced. Although the prospects of the design and engineering of radiative cooling products appear promising for both buildings and EVs, further investigations are necessary to evaluate scalability, durability, and performance based on factors such as geography and meteorology. [ABSTRACT FROM AUTHOR]

A composite container for an electric vehicle (EV) battery module filled with a phase-change material (PCM) was experimentally tested at various discharge rates. The average cell temperatures at 1 C, 2 C, and 4 C discharge rates, respectively, might reach 38 °C, 50 °C, and 70 °C in the absence of any heat-absorbing material. The temperature was noticeably lower with PCM present than with a conventional battery module. For instance, at 4 C discharge rates, none of the battery cells inside the PCM-filled module were able to reach 70 °C. Unfortunately, the PCM addition also degraded the composite's tensile qualities. Further investigations used Paraffin-20 and Caprylone since PCMs provide a notably different thermal performance due to their distinctive latent heat profiles. It was observed that a high melting temperature of the paraffin mixture, despite its slightly lower latent heat capacity compared to Caprylone, could lead to a more uniform temperature. Overall, both PCMs can be used as passive protection against any potential thermal abuses in EV battery modules, while in terms of mechanical strength, the use of a composite reinforcement material is strongly encouraged. [ABSTRACT FROM AUTHOR]

Electric vehicles (EVs) have been garnering wide attention over conventional fossil fuel-based vehicles due to the serious concerns of environmental pollution and crude oil depletion. In this article, we have conducted a systematic literature survey to explore the battery raw material supply chain, material processing, and the economy behind the commodity price appreciation. We present significant areas of concern, including resource reserves, supply, demand, geographical distribution, battery reuse, and recycling industries. Furthermore, details of the battery supply chain and its associated steps are illustrated. The authors believe the presented study will be an information cornerstone in boosting manufacturing and understanding the key components and materials required to facilitate EV battery production. Further, this study discusses the major industries, and their policies and global market share in each material category. [ABSTRACT FROM AUTHOR]

Maximum power point tracking (MPPT) through an effective control strategy increases the efficiency of solar panels under rapidly changing atmospheric conditions. Due to the nonlinearity of the I–V characteristics of the PV module, the Sliding Mode Controller (SMC) is considered one of the commonly used control approaches for MPPT in the literature. This paper proposed a Backstepping SMC (BSMC) method that ensures system stability using Lyapunov criteria. A fuzzy inference system replaces the saturation function, and a modified SMC is used for MPPT to ensure smooth behavior. The proposed Fuzzy BSMC (FBSMC) parameters are optimized using a Particle Swarm Optimization (PSO) approach. The proposed controller is tested through various case studies on account of MPP's dependence on temperature and solar radiation. The controller performance is assessed in partial shading conditions as well. The simulation results show that less settling time, a small error, and enhanced power extraction capability are achieved by applying the PSO-based FBSMC approach compared to the conventional BSMC- and ABC-based PI control presented in previous research in different scenarios. Moreover, the proposed approach provides faster adaptation to temperature and solar radiation variation, ensuring faster convergence to the MPP. Finally, the robustness of the proposed controller is validated by providing variation within the system components. The result of the proposed controller clearly indicates the lowest value of RMSE measured between PV voltage and the reference voltage, as well as the RMSE between PV power and maximum power. The results also show that the proposed MPPT controller exhibits the highest dynamic efficiency and mean power. [ABSTRACT FROM AUTHOR]

Photovoltaic systems (PVs) are promising low-carbon technologies playing a major role in the electricity business. In terms of voltage variation and feeder usage capacity, high PV penetration levels have significant technical implications for grid stability, particularly in Low Voltage (LV) networks. This paper presents a comprehensive PV integration analysis on real-life residential LV networks in Malta using recorded smart metering data. The methodology framework and tools developed are highlighted through step-by-step results on their usefulness. First, at the substation level, an LV network with seven LV feeders is analyzed using Monte Carlo simulations and OpenDSS. Then, Cumulative Distribution Functions (CDFs) are extracted to establish the likelihood of LV network challenges. Afterwards, 95 multi-feeder analyses assess the impact assessment on the first occurrence of LV network challenges and predominant issues. Finally, a Regression Analysis Tool, considering the regression's standard error, is built for seven feeder characteristics to predict the impacts. The stochastic processes reveal strong relationships with feeder characteristics that are helpful for network planning and operations. However, the Maltese grid currently has less than 20% PV penetration at any LV feeder. Hence, significant technological hurdles are absent. [ABSTRACT FROM AUTHOR]

This paper formulates a maximum power point tracking (MPPT) technique that accurately tracks the maximum power point of photovoltaic (PV), which undergoes simultaneous or independent sudden changes in load resistance and irradiance. The proposed algorithm is fundamentally divided into three parts; current and voltage perturbation algorithm (IPA/VPA), perturbation step-size reduction algorithm (PSSRA) and a deviation avoidance loop. The use of dual perturbation parameters using IPA and VPA ensures high tracking speed. PSSRA iteratively reduces the perturbation step-size of IPA and VPA and helps in reducing the power oscillations around MPP. Finally, a deviation avoidance loop is developed to detect a change in irradiance by examining the sign of the slope of the two power curves, namely P-V and P-I. The algorithm compares the per unit change in voltage and current of PV, to determine a simultaneous change in both irradiance and load resistance. The proposed algorithm is compared with two recently developed MPPT algorithms. The results show that the proposed technique can track the MPP with high speed and low steady-state oscillations and does not deviate from the MPP tracking path regardless of fast changes in irradiance and load resistance. [ABSTRACT FROM AUTHOR]

Comparisons between different laboratories on long‐term stability analyses of perovskite solar cells (PSCs) is still lacking in the literature. This work presents the results of an interlaboratory study conducted between five laboratories from four countries. Carbon‐based PSCs are prepared by screen printing, encapsulated, and sent to different laboratories across Europe to assess their stability by the application of three ISOS aging protocols: (a) in the dark (ISOS‐D), (b) under simulated sunlight (ISOS‐L), and (c) outdoors (ISOS‐O). Over 1000 h stability is reported for devices in the dark, both at room temperature and at 65 °C. Under continuous illumination at open circuit, cells survive only for few hours, although they recover after being stored in the dark. Better stability is observed for cells biased at maximum power point under illumination. Finally, devices operate in outdoors for 30 days, with minor degradation, in two different locations (Barcelona, Spain and Paola, Malta). The findings demonstrate that open‐circuit conditions are too severe for stability assessment and that the diurnal variation of the photovoltaic parameters reveals performance to be strongly limited by the fill factor, in the central hours of the day, due to the high series resistance of the carbon electrode. [ABSTRACT FROM AUTHOR]

Plastic-based photovoltaic (PV) technology, also known as organic photovoltaic (OPV), has the development promise to be one of the third PV generation technologies, practically where sunlight reaches a surface area both indoors and outdoors. This paper presents the economic forecast for solar electricity using OPV technology based on a 1 kWp domestic system. With reference to OPV roll-to-roll manufacturing, the paper discusses lifetime, efficiency, and costs factors of this emerging PV technology. Taking an outlook of historic PV technology developments and reflect future anticipated technology developments, the future levelised electricity cost is calculated using system life cycle costing techniques. Grid parity at levelised electricity cost below 25 c/kWh may already be reached within 10 years' time, and the technology would have been widespread, assuming a typical southern Europe average solar irradiance of 1700 kWh/m2/year. The influence of solar irradiance and the way the module performs over long periods of time expecting various degradation levels is studied using sensitivity analysis. Eventually, the financial attractiveness to mature silicon-based PV technology may decline suddenly as financial support schemes such as the popular Feed-in-Tariffs dry out. This would give rise to other promising solutions that have already been proven to be less energy intensive and cheaper to produce but may require a different integration model than present technologies. This paper demonstrates that under no financial support schemes emerging PV technologies such as OPV will manage to attract business and further developments. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

At current usage levels, short rotation coppice (SRC) biomass could be considered as an untapped resource. There is a worldwide interest to extend its sustainable production significantly in a decade to come. However, the cultivation of energy crops is very site-specific and the exploitation of SRC biomass is a relatively new trend in biomass application for heat and power production with little information on its cultivation patterns and appropriate combustion technologies. In fact, documented biomass conversion technologies’ impacts in the energy sector and their commercialisation are limited. This paper aims to present a summary of technical characteristics for different biomass conversion technologies. These characteristics are not necessarily unique to all types and possible modifications of the biomass conversion technologies applied for many countries. However, the lack of technical knowledge have created situations that were previously impossible to be solved without the aid of numerous research and development activities. The developers did not capture all of the economic benefits that the technology provides which would help to reach its technical accomplishment and commercial execution. [ABSTRACT FROM AUTHOR]