International and regional measures against Somali piracy: genuine but misguided

The increasing piracy in the Gulf of Aden has captured the attention of the international community. Somali pirates have proven their ability to attack all types of vessels from small yachts to giant oil supertankers. As a result, series of serious efforts by international community have been undertaken to put an end to this emerging phenomenon. These include, deploying the biggest anti-piracy fleet in modern history, permitting warships to purse pirates in Somali territorial waters under special conditions, and the new approach toward establishing international tribunals to prosecute pirates. However, there is a growing need to re-examine Somali piracy counter-measures and evaluate their effectiveness. In this respect, a profound analysis of the circumstances surrounding Somali piracy is required. It is crucial to question to what extent the current anti-piracy efforts respond to the original roots of the problem and the needs of Somalia. This research critically analyzes anti-piracy efforts taken by the international community and its impact on the ground. In this regard, a holistic approach was taken to examine Somali piracy. Any anti-piracy measures have to respond to the roots of the problem in order to guarantee their effectiveness in the long-term. Undoubtedly, building a military coalition to patrol ships passing through Somali waters is a needed measure to deter pirates. However, it is crucial to ask ourselves to what extent such measures are sustainable and to what extent it responds to the roots of the problem. Thus, the international community needs to look to the bigger picture and to carefully analyze factors contributing to spread of piracy especially off the coast of Somali. The solution to piracy may lie on the land not in the sea

Potential Induced Degradation in Photovoltaic Modules : A Review of the Latest Research and Developments

Photovoltaic (PV) technology plays a crucial role in the transition towards a low-carbon energy system, but the potential-induced degradation (PID) phenomenon can significantly impact the performance and lifespan of PV modules. PID occurs when a high voltage potential difference exists between the module and ground, leading to ion migration and the formation of conductive paths. This results in reduced power output and poses a challenge for PV systems. Research and development efforts have focused on the use of new materials, designs, and mitigation strategies to prevent or mitigate PID. Materials such as conductive polymers, anti-reflective coatings, and specialized coatings have been developed, along with mitigation strategies such as bypass diodes and DC-DC converters. Understanding the various factors that contribute to PID, such as temperature and humidity, is critical for the development of effective approaches to prevent and mitigate this issue. This review aims to provide an overview of the latest research and developments in the field of PID in PV modules, highlighting the materials, designs, and strategies that have been developed to address this issue. We emphasize the importance of PID research and development in the context of the global effort to combat climate change. By improving the performance and reliability of PV systems, we can increase their contribution to the transition towards a low-carbon energy system

Current limiter circuit to avoid photovoltaic mismatch conditions including hot-spots and shading

Photovoltaic (PV) hot-spots are considered as one of the main reliability issues for PV modules. Although PV modules are capable to tolerate over-temperature, the hot-spots can lead to accelerated aging and, sometimes, to sudden failure with possible risk to fire. The common-practise for mitigating this phenomenon is the adoption of the conventional bypass diode circuit, yet, this method does not guarantee a decrease in the temperature of hot-spotted solar cell. Therefore, in this paper, we present the development of a new current limiter circuit that is capable of mitigating the current flow of PV modules affected by mismatch conditions including partial shading and hot-spotting phenomenon. The foundation of the proposed circuit is fundamentally based on an input buffer which allows high impedance input voltages, and an operational amplifier circuit which controls the current flow of an integrated MOSFETs. Hence, to allow the control of the amount of current passing though mismatched PV sub-strings, and therefore, increase the output power generation. Detailed circuit simulations and multiple experiments are presented to evidence the capability of the circuit. In contrast, the average dissipated power of the circuit is limited to 0.53 W

Photovoltaic Hot-Spots Fault Detection Algorithm using Fuzzy Systems

Faults in photovoltaic (PV) modules, which might result in energy loss and reliability problems are often difficult to avoid, and certainty need to be detected. One of the major reliability problems affecting PV modules is hot-spotting, where a cell or group of cells heats up significantly compared to adjacent solar cells, hence decreasing the optimum power generated. In this article, we propose a fault detection of PV hot-spots based on the analysis of 2580 PV modules affected by different types of hot-spots, where these PV modules are operated under various environmental conditions, distributed across the U.K. The fault detection model comprises a fuzzy inference system (FIS) using Mamdani-type fuzzy controller including three input parameters, namely, percentage of power loss (PPL), short circuit current (I sc ), and open circuit voltage (V oc ). In order to test the effectiveness of the proposed algorithm, extensive simulation and experimental-based tests have been carried out; while the average obtained accuracy is equal to 96.7%

Field Study of Photovoltaic Systems with Anti-Potential-Induced-Degradation Mechanism: UVF, EL, and Performance Ratio Investigations

The potential-induced degradation (PID) of photovoltaic (PV) modules is one of the most extreme types of degradation in PV modules, where PID-affected modules can result in an almost 25% power reduction. Understanding how module defects impact PID is key to reducing the issue. Therefore, this work investigates the impact of an anti-PID inverter on PV modules throughout three years of field operating conditions. We used electroluminescence (EL), ultraviolet fluorescence (UVF), and thermography imaging to explore the varieties of an anti-PID inverter connected to a PV string. It was discovered that a PV string with an anti-PID inverter could improve the output power of the modules by 5.8%. In addition, the performance ratio (PR) was equal to 91.2% and 87.8%, respectively, for PV strings with and without an anti-PID inverter

Investigating defects and annual degradation in UK solar PV installations through thermographic and electroluminescent surveys

As the adoption of renewable energy sources, particularly photovoltaic (PV) solar, has increased, the need for effective inspection and data analytics techniques to detect early-stage defects, faults, and malfunctions has become critical for maintaining the reliability and efficiency of PV systems. In this study, we analysed thermal defects in 3.3 million PV modules located in the UK. Our findings show that 36.5% of all PV modules had thermal defects, with 900,000 displaying single or multiple hotspots and ~250,000 exhibiting heated substrings. We also observed an average temperature increase of 21.7 °C in defective PV modules. Additionally, two PV assets with 19.25 and 8.59% thermal defects were examined for PV degradation, and results revealed a higher degradation rate when more defects are present. These results demonstrate the importance of implementing cost-effective inspection procedures and data analytics platforms to extend the lifetime and improve the performance of PV systems

Recovery of Photovoltaic Potential-Induced Degradation Utilizing Automatic Indirect Voltage Source

Potential-induced degradation (PID) of photovoltaic (PV) modules is one of the most severe types of degradation in modern modules. PID can affect crystalline silicon PV modules, and while extensive studies have already been conducted in this area, the understanding of how to recover PID is still incomplete, and it remains a significant problem in the PV industry. In this paper, an electronic circuit that can mitigate the impact of PID in PV modules is utilized. This was achieved by inducing the PV string of 1000 V when a threshold current of 100 mA is detected. A microcontroller was used to manage the current sensor data and actuate the whole circuit. The impact of the proposed circuit on PID affected PV modules are (i) improve the electroluminescence regeneration, (ii) increase the output power by up to 30% of newly PID affected modules, and up to 7.8% for old modules, (iii) reduce their temperature, known by hotspots, and (iv) despite the variations in the solar irradiance and temperature, the recovery of the PID can be obtained within 15 days or less

Field study on the severity of photovoltaic potential induced degradation

Photovoltaic (PV) systems can be affected by different types of defects, faults, and mismatching conditions. A severe problem in PV systems has arisen in the last couple of years, known as potential-induced degradation (PID). During the early installation stage of the PV system, the PID may not be noticed because it appears over time (months or years). As time passes, it becomes more apparent since the output power may drop dramatically. We studied PV modules over the course of three years that were affected by PID. An electroluminescent and thermal imaging technique helped discover the PID. PID appeared in PV modules after being in different fields for 4–8 months, resulting in a 27–39% drop in power. An anti-PID box was fitted during the second year of the PV operation to recover the PID. Accordingly, it has stabilized the power degradation, but it could not restore the performance of the affected PID modules as compared with healthy/non-PID modules

A Comparative Study of Bifacial versus Monofacial PV Systems at the UK Largest Solar Plant

This paper presents an extensive analysis of the United Kingdom's largest bifacial photovoltaic (PV) power plant, located in North Yorkshire. Commissioned in January 2020, this trailblazing facility, with a total installed capacity of 34.7 MW, is a benchmark for the evaluation of bifacial solar technology within the region. This pioneering study provides a thorough comparative assessment of bifacial and monofacial PV systems through a methodical investigation of their energy production, degradation rates, and spectral responses over a four-year operational period. Our findings reveal that bifacial PV modules, distributed across four segments of the power plant, demonstrate a remarkable average power gain ranging between 15.12% and 17.31% compared to monofacial modules. Despite experiencing marginally higher annual degradation rates—1.17% for bifacial compared to 0.91% for monofacial systems—bifacial modules show superior resilience and energy yield, particularly during winter months when albedo effects are pronounced due to snow coverage. The study also highlights the strategic importance of spectral response analysis in optimizing PV performance. Bifacial modules have shown greater efficiency in capturing infrared radiation, a property that could be exploited to enhance overall energy yield in specific environmental conditions. The empirical data indicate a consistent performance of bifacial modules with an average normalized energy output clustering around the expected efficiency level. Therefore, the results of this study are pivotal for understanding the practical implications of deploying bifacial PV technology on a large scale. They provide valuable data for stakeholders in the solar energy sector, guiding future installations and innovations in solar panel technology

Investigating the stability and degradation of hydrogen PEM fuel cell

The hydrogen proton exchange membrane (PEM) fuel cells are promising to utilize fuel cells in electric vehicle (EV) applications. However, hydrogen PEM fuel cells are still encountering challenges regarding their functionality and degradation mechanism. Therefore, this paper aims to study the performance of a 3.2 kW hydrogen PEM fuel cell under accelerated operation conditions, including varying fuel pressure at a level of 0.1–0.5 bar, variable loading, and short-circuit contingencies. We will also present the results on the degradation estimation mechanism of four fuel cells working at different operational conditions, including high-to-low voltage range and high-to-low temperature variations. These experiments examine over 180 days of continuous fuel cell working cycle. We have observed that the drop in the fuel cells' efficiency is at around 7.2% when varying the stack voltage and up to 14.7% when the fuel cell's temperature is not controlled and remained at 95 °C