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In addition to the use of waste heat from the vessel’s exhaust gas to save energy onboard, reduce the carbon emissions of the ship, and combine the characteristics of ship waste heat, mathematical modeling and testing of ship waste heat temperature difference power generation were carried out in this study. Finally, an experimental platform for temperature differential power generation was established to assess the impact of influencing agents on the efficiency of temperature differential power generation. The results show that the effect of different thermally conductive greases on the efficiency of temperature differential power generation tablets is basically the same. In addition, the rate of flow of cooling water, the cooling plate area, and the heat source temperature have more significant effects on the open-circuit voltage and maximum output power. The results show that the maximum power output growth rate increases with increasing cooling water flow, reaching 8.26% at 4 L/min. Likewise, increasing the heat source temperature enhances the maximum output power growth rate by 15.25% at 220 °C. Conversely, the maximum output power of the temperature difference power generation device decreases as the cooling plate area increases, and the maximum output power reduction rate is 15.25% when the cooling plate area is 80 × 200 mm2 compared to the case of using a cooling plate area of 80 × 80 mm2. Moreover, the maximum output power of the temperature differential power generation device reaches 13.6 W under optimal conditions. Assuming that the temperature difference power generation plate is evenly distributed on the tailpipe of the 6260ZCD marine booster diesel engine, it could save approximately 5.44 kW·h electric power per hour and achieve a reduction in CO2 emissions of 0.3435 kg per hour.

In order to investigate the effect of different influencing factors on the application of temperature differential power generation in the ship exhaust gas and to explore the potential of waste heat recovery and the utilization of exhaust gas during ship travel, an experimental system based on the temperature differential power generation of ship exhaust gas in the marine environment was established. The maximum output power and the maximum efficiency of each temperature-difference power generation module were theoretically calculated. The results showed that the insulation material and the salt water (seawater) had little effect on the efficiency of the temperature differential power generation modules. Conversely, the installation pressure, the heat transfer oil, the cooling water temperature (seawater temperature), and the heat source temperature (exhaust gas pipe temperature) had a great influence on the open-circuit voltage and the maximum output power. The thermally conductive silicone grease and the cooling water temperature of 10 °C increased the open-circuit voltage by 31.54% and 18.95%, respectively, and increased the maximum output power by 82.05% and 51.79%, respectively. The maximum output of a single temperature differential power generator reached 63.5% when using an installation pressure of 3 bar, a cooling water temperature of 20 °C, double-layer aluminum insulation, and thermally conductive silicone grease. Finally, this study provides relevant data support for using temperature differential power generation devices for ship exhaust gas.

Sea‐land breeze (SLB) is particularly important in coastal regions and can affect weather conditions and air quality. However, previous research on SLB has predominantly focused on specific locations, with varying methodologies used to identify SLB days (SLBDs), leading to a limited understanding of long‐term SLB trends across extensive coastal areas. Here, a unified method for gridded reanalysis dataset to identify SLBDs is proposed for the first time, and the trend, influencing factors, and effects on air pollutant recirculation over coastal China are explored. The results demonstrate that SLBDs have increased in 70% of China's coastal areas in the past five decades. Key driving factors include the growing temperature contrast between land and sea, increasing solar radiation, and the weakening background winds. The study suggests that the increasing SLB frequency will enhance air pollutant accumulations, making it challenging to manage air quality effectively in these coastal areas. Plain Language Summary Sea‐land breeze (SLB), a prevalent local circulation driven by the temperature contrasts between land and sea, significantly impacts regional weather, urban environments, wind power generation, and fisheries. While detailed case studies have explored the local characteristics of SLB in different specific coastal regions, the long‐term trends and underlying mechanisms of SLB have received less attention, particularly in the context of global warming. The rapid advancement of meteorological reanalysis data with high spatial and temporal resolutions now allows for a comprehensive analysis of these long‐term trends across extensive coastal regions. This study introduces a novel method to identify SLB days (SLBDs) over coastal areas of China using gridded reanalysis datasets (ERA5). Over the past 53 years, we find that the frequencies of SLB have increased in more than 70% of coastal China. Rising temperature differences between land and sea, increasing solar radiation, and weakening wind fields are key factors contributing to the trend. A weakening recirculation index suggests that increased SLBDs may exacerbate air quality issues in coastal areas. The method proposed in this study for identifying SLBDs can be extended to other regions worldwide, yielding new insights into the regional dynamics of SLB and their broader environmental impacts. Key Points A comprehensive criteria for gridded reanalysis dataset to identify SLBDs is proposed SLB frequencies in coastal China have increased in the past five decades The rising land‐sea temperature contrast drives the increase in SLB frequencies

The ocean thermal energy conversion (OTEC) systems, as renewable energy-based power plants, have the potential to play a significant role in meeting future electricity demands due to the vast expanse of the world's oceans. These systems employ the temperature difference between surface ocean waters and deep ocean waters to drive a thermodynamic cycle and produce electricity. The temperature of deep ocean waters, approximately 1000 m below the surface, is approximately 4 °C, while surface ocean temperatures typically range between 20 and 30 °C. The generated power of OTEC systems is dependent on these temperature differences and may vary with changes in surface ocean temperatures. In this study, the main focus is to find the impact of temperature variation on the failure rates of OTEC system components and the generated power output of these plants. The findings indicate that as the demand for the power system increases, its reliability decreases. In order to improve the reliability of the power system, the integration of a new generation unit, such as the close cycle OTEC power plant under investigation, could be necessary. The findings also indicate the importance of considering temperature variation in the evaluation of the reliability of such types of power plants based on renewable energy.

This study examines the effects of dust accumulation on the performance of photovoltaic (PV) panels in an urban environment through 1 month of field experiments. Three PV panels—clean (P1), lightly soiled (P2), and heavily soiled (P3)—were installed on a rooftop test bed in two configurations: horizontal and latitude‐tilted (45° North), using black tar paper and brown cellulose fiberboard as roofing materials. On the reference day, the panels showed minimal performance differences, with discrepancies of 0.37% in maximum power ( P max ) and 0.43% in short‐circuit current ( I sc ). However, dust accumulation led to significant power losses in P3, averaging 23.4% in the horizontal position and 15% when tilted. P2 showed minor losses (1%–3%) throughout. Thermal monitoring revealed that dust raised the front surface temperatures of the soiled panels, while the clean panel exhibited the highest back surface temperatures. The greatest temperature differences occurred in the tilted configuration, with a maximum of 6.03 K on the front surface. Roofing material also influenced thermal behavior, with the black tar paper absorbing more heat than the cellulose fiberboard. The results highlight the importance of regular panel cleaning and optimal tilt angles to minimize dust‐related performance losses, providing insights for improving the efficiency of PV systems in built environments.

In the ocean thermal energy conversion (OTEC) system, electrical power is generated by exploiting the temperature difference between cold deep seawater and warm surface water. This study introduces an innovative method that uses a solar collector to increase the temperature of the water entering the evaporator and a wind turbine to increase the useful power, thereby increasing the energy efficiency and power output of the cycle. The research findings indicate that the proposed cycle achieves an average net production power of 36.63 megawatts, with energy productivity and exergy at 9.70% and 29.12%, respectively. Additionally, freshwater production has increased by 170.26% compared to the base cycle. A sensitivity analysis of various parameters was also conducted on the proposed cycle, which demonstrated a reduction of 89.69 tons in carbon dioxide emissions. Finally, to optimize the designed system, the response level multiobjective optimization method has been used to find the best set of objective functions and decision variables. The four objective functions of this optimization included exergy efficiency, total system energy, production work, and system cost rate.

In electronic components, systems for thermal management considerably affect the components’ performance. Rapid advances in computer processing unit chips have led to substantial increases in their power consumption and heat generation. Many researchers have focused on studying the use of phase change materials (PCMs) to stabilize the temperature of electronic components. These materials regulate the temperature by absorbing latent heat during phase transitions. However, despite their high latent heat capacity, the low thermal conductivity of PCMs results in prolonged phase change duration time. In order to address this limitation, both industry and academia have directed significant attention toward enhancing the heat transfer efficiency of PCMs. This study investigates the effect of the volume fraction of PCM, specifically paraffin, on the thermal performance of heat sinks used in electronic components. The research compares the temperature profiles of heat sinks not equipped with fins, with circular pin fins, and with square pin fins under various PCM volume fractions to evaluate their performance while a high latent heat PCM was used. By way of designing different heat sinks, PCM volume fractions, and different power levels to investigate the final base temperature, PCM temperature distribution uniformity, and Stefan number (Ste). When the fin volume fraction was fixed at 9% for heat sink equipped with circular pin fins, and with square pin fins, the heat sink equipped with circular pin fins exhibited superior thermal performance to the square fins and no fins heat sinks. Moreover, among all examined heat sinks that equipped with circular pin fins exhibited the lowest base temperature, highest heat transfer efficiency, and smallest rate of increase in base temperature. In addition, the higher PCM volume fraction at 0.9 shows the lower base temperature. For all designed heat sinks, the cooling effect of base temperature was achieved by adding PCM which is stronger when the heat flux was 1.6 and 2.4 kW/m 2 than 0.8 kW/m 2 . The improvement achieved in the cooling performance with an increase in φ was greater at a higher heat flux. On the other hand, at a heat flux of 2.4 kW/m 2 and PCM volume fraction of 0.9, the heat sink equipped with square pin fins exhibits better PCM temperature distribution uniformity than the heat sink equipped with circular pin fins and with no fins, and measured points maximum temperature differences are 3.75, 6.30, and 9.75°C, respectively. Furthermore, this study examined how the Ste affected the time it took to reach different temperatures in the three designed heat sinks. For all three designs, the time it took to reach different temperatures decreased with an increase in the Ste. When the Ste was 12.55, among the designed heat sinks, that equipped with square pin fins was the slowest in reaching 50°C. However, at Stes of 25.10 and 37.65 that equipped with circular pin fins was the slowest in reaching 50°C. Moreover, at Stes of 25.10 and 37.65 that equipped with circular pin fins was the slowest in reaching 55 and 60°C.

Interest in thermoelectric generators (TEGs) for waste heat recovery (WHR) and geothermal energy has grown significantly in recent years due to the ability to convert low‐grade thermal energy into electricity, which is essential to reduce carbon emissions. One of the main challenges in TEG power generation is the expandability and the number of layers in TEG devices. The currently reported maximum number of layers is six. In this study, the expandable TEG devices with different number of layers, up to 20, were designed and manufactured. The field tests have been then conducted with these TEG devices using the waste heat from a coal bed methane power plant at a temperature of around 80°C. To our best knowledge, this is the lowest temperature at which TEG field tests have been implemented. At a flow rate of about 3 m 3 /hr, a TEG unit with a volume of about 3 m 3 can generate a power of 15 kW at a temperature difference of 60°C. The power density and power per unit area of the TEG are investigated and compared to those of diesel generators and photovoltaic panels at different temperature differences. Furthermore, to offer guidance for the commercial‐scale implementation of TEG, we have estimated the fabrication and installation costs, as well as the levelized cost of electricity, across various temperature differences. The results indicate that TEG is a feasible and promising technology for large‐scale power generation and WHR.

Heat generation and accumulation during working schemes of the lithium-ion battery (LIB) are the critical safety issues in hybrid electric vehicles or electric vehicles. Appropriate battery thermal management is necessary for ensuring the safety and continuous power supply of rechargeable LIB modules. In this study, thirty cylinder 18650-type cells were fabricated a 6S5P battery module with a 2-mm spacing between cells to evaluate exothermic trajectories. The modules, equipped with a forced-air cooling system, were charged at 1 C-rate and discharged at 1, 1.5, and 2 C-rates for three cycles in each test; thermocouples were connected to the cells to track the variances in temperature and voltage. The efficiency of the developed forced-air cooling system was estimated to be 73.0% in case 1 with the 1 C discharge rate, and the temperature difference (TD) was less than 5.0 °C. The maximum temperature ( T max ) of this case was maintained below 45.0 °C showing uniform heat distribution. Moreover, extreme heat accumulation developed inside the module and damaged the adjacent LIBs during fast 2 C discharge test. Our TD testing showed that a forced-air cooling system in the LIB module provides effective heat dispersion under normal discharge conditions.

In liquefied natural gas (LNG) power plants, a significant amount of heat and cold energy is consumed to capture and store carbon dioxide (CO2) emitted during the combustion of fossil fuels. The proposed system addresses this problem by utilizing the temperature difference between waste heat and cold energy as a power source to generate electricity. In this study, a novel waste heat and cold energy recovery system for a postcombustion LNG power plant was developed using an organic Rankine cycle (ORC). To design the proposed system, a process model was developed with the following five parts: (i) LNG vaporization, (ii) natural gas combined cycle (NGCC), (iii) amine scrubbing, (iv) CO2 liquefaction, and (v) CO2 injection. In the proposed system, waste LNG cold energy is used for lean amine cooling and CO2 liquefaction. The liquefied CO2 was pressurized to meet the injection pressure requirements. The ORC uses high-temperature exhaust gas from the NGCC as the heat source and high-pressure liquefied CO2 as the heat sink. The economic feasibility of the proposed system was demonstrated by an economic assessment, with the net profit evaluated by a sensitivity analysis considering variations in water, electricity, and equipment costs. Consequently, the proposed system exhibited an 18.6% increase in net power production compared to the conventional system. In addition, the net profit of the proposed system exhibited a 76.7% increase compared to the conventional system, confirming its economic feasibility.