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- 摘要
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- 实验方案
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Plasmonic Nanomolecules: Electrochemical Resolution of 22 Electronic States in Au <sub/>329</sub> (SR) <sub/>84</sub>
摘要： Gold nanomolecules are atomically precise gold thiolate nanoparticles. They show size-dependent optical and electrochemical properties due to the quantization effects. The optical properties are well explored. However, there is still a void in understanding their electrochemical properties and probing higher oxidation states. We report the 22 electronic states of a plasmonic nanocrystal molecule with 329 gold atoms and 84 phenylethanethiolate ligands in a wide electrochemical potential (～4 V) window. We provide a comprehensive understanding of the electrochemical properties as a function of size and composition of gold nanomolecules. This report also demonstrates that they behave like quantum capacitors and their capacitance varies linearly with size. The effect of ligand monolayer and core composition on the electrochemical properties was demonstrated using a 144-metal atom system. These results would help us design applications using the gold and alloy nanomolecules in photovoltaics, catalysis, sensors, and energy storage devices.
关键词： electrochemical properties,energy storage,Gold nanomolecules,plasmonic nanocrystal,quantum capacitors
更新于2025-09-12 10:27:22
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Determining the size of energy storage system to maximize the economic profit for photovoltaic and wind turbine generators in South Korea
摘要： This study identifies the optimal size of an Energy Storage System (ESS) for Photovoltaic (PV) and Wind Turbine (WT) generators under current Korean government policies. The government has pledged to promote the use of ESS with PV and WT generation to reduce the variability and uncertainty of renewable energy generation. The proposed algorithm determines the optimal ESS size required for PV and WT suppliers to maximize economic profit by using their historical generation profiles and compensation price. Net Present Value (NPV) is used as an economic parameter to determine the optimal size of ESS and consequently, the optimization indicates the maximization of NPV in this study. Furthermore, this paper proposes a methodology to estimate the size of ESS when there is insufficient information for future PV and WT suppliers. To verify the proposed algorithms, actual PV and WT generation profiles as well as the compensation price in South Korea are used. The simulation results indicate that the optimal capacity ratio between Renewable Energy Source (RES), ESS battery, and ESS PCS is determined as 1:3.3:0.7 and 1:3:1 for PV and WT respectively. Furthermore, the ESS size estimated by the proposed methodology shows a marginal difference from the optimal size, with an error of less than 3% for PV and 0% for WT.
关键词： Wind Turbine (WT),Photovoltaic (PV),Economic analysis,ESS sizing,Estimation model,Energy storage system (ESS)
更新于2025-09-12 10:27:22
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Assessment of the Carbon and Cost Savings of a Combined Diesel Generator, Solar Photovoltaic, and Flywheel Energy Storage Islanded Grid System
摘要： The use of diesel generators to provide power for islanded grids has been the technology of choice but they generate substantial carbon emissions unless the part or all the fuel comes from a renewable source. Notwithstanding this, the engine must be sized to meet maximum demand and will operate ine?ciently at part load most of the time, which is particularly bad for a synchronous constant speed engine. Given the availability of low cost solar photovoltaic (PV) systems, it is very enticing to ?t a diesel generator and allow the engine to be turned o? during PV generation. However, this combination will not work without some form of energy storage since it takes time for the engine to start, leading to gaps in supply and instability of the system. Lithium-ion batteries are typically considered to be the best solution to this problem because they have a high response rate, costs are lower, and they are available as products. However, they will su?er from the limited cycle and calendar life due to high cycling requirements in the application described. It is, therefore, proposed that a ?ywheel system could o?er a lower lifetime cost alternative since only short duration bridging power storage is needed and ?ywheels of appropriate design can o?er lower power cost than Lithium-ion battery systems. Flywheels are particularly attractive since they have a very high calendar with almost an in?nite cycle life and are fully recyclable at the end of life. This research, therefore, presents an assessment of the ?ywheel energy storage system (FESS) as an alternative to electrochemical batteries to supplement solar PV systems backed up by diesel generators. The model of an islanded PV system combined with a diesel generator and a FESS supplying power to a residential load is implemented in MATLAB/Simulink. The results of the analysis for the cases with and without storage based on a number of di?erent charge-discharge strategies provide evidence to support this hypothesis.
关键词： dynamic model,standalone hybrid system,solar photovoltaic system,backup diesel generator,flywheel energy storage
更新于2025-09-12 10:27:22
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Experimental investigation of a photovoltaic thermal collector with energy storage for power generation, building heating and natural ventilation
摘要： A phase change material (PCM) can be used for thermal management of photovoltaics and thermal energy storage. This paper presents a photovoltaic thermal (PVT) system integrated with a PCM as a thermal storage medium for managing the photovoltaic temperature and together with a ventilation duct for preheating supply air or natural ventilation of a building. The novelty of the integrated PVT/PCM system lies in using the PCM as a passive technique not only for PV cooling but also for building heating and ventilation. Experiments have been carried out on a prototype PVT system for different sizes of PCM. The results show that a 30 mm thick PCM layer with a phase change temperature of 25oC can maintain the PV temperature below 45oC and improve the PV electrical efficiency by 10% for about 210 minutes under 600 W/m2 insolation. Increasing the PCM thickness by 10 mm increases the time for thermal control by 60 to 70 minutes. The PVT/PCM system is able to generate a 15 L/s ventilation rate in a vertical duct of 1100 mm wide, 1200 mm high and 100 mm deep during the melting phase and at least 20 L/s during the solidification phase. Use of metal fins to enhance heat transfer in the PCM can increase the PV electrical efficiency further by 3% and the ventilation rate by 30%.
关键词： energy storage,Photovoltaics,phase change material,natural ventilation,thermal management,solar absorber
更新于2025-09-12 10:27:22
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Attachable micropseudocapacitors using highly swollen laser-induced-graphene electrodes
摘要： For powering wearable electronics, extensive research has been directed toward microscale flexible and stretchable energy-storage devices. Microsupercapacitors, though promising candidates, remain limited in terms of design flexibility, scalability, reusability, and compatibility with general substrates. This paper reports a high-performance sticker-type flexible microsupercapacitor using highly swollen reduced-graphene-oxide electrodes fabricated by an ultrashort-pulse laser to promote full active-site and durability of the electrodes. Our sticker-type flexible micropseudocapacitor provides a comparable volumetric energy density of 1.08 mWh cm-3 and 13 times higher volumetric power density of 83.5 mW cm-3 compared to conventional lithium thin-film batteries. Bio-inspired surface modifications are additionally applied to the reduced-graphene-oxide electrodes, which provides a six-fold increase (10.38 mF cm?2) of the areal capacitance. A 6 × 2 micropseudocapacitor array embedded in a sub-millimeter thin PDMS film adheres to safety goggles and successfully powers a μ-LED. The total capacitance of the array is maintained at ~97% of its original value after 200 repetitive attachments and detachments showing good durability. In addition, the sticker-type micropseudocapacitor array shows a stable performance under repeated deformation, and up to ~99% of capacitance retention after 200 bending cycles. This novel re-attachable flexible micropseudocapacitor will expedite the widespread use of flexible and wearable devices.
关键词： laser direct writing,attachable energy storage device,laser-induced graphene,pseudocapacitor,microsupercapacitor
更新于2025-09-12 10:27:22
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Photovoltaic active power control based on BESS smoothing
摘要： The power fluctuation of photovoltaic (PV) is harmful to power systems, so the battery energy storage system (BESS) was applied to smooth power fluctuation in PV. At present, the main ways to get configuration of BESS are low-pass filter and spectrum compensation, which have some drawbacks. In this paper, a method that combines empirical mode decomposition (EMD) with wavelet analysis (WA) is proposed to get grid-connected active power expectation of PV properly. Based on simulation of PV output, the minimum sizing of BESS is determined by different batteries’ state-of-charging (SOC) and efficiency. Comparing traditional low-pass filter and spectrum compensation, this method not only acquires the capacity of BESS accurately, but also improves the effect to smoothing power fluctuation of PV effectively. Finally, a case is proposed to verify correctness of the theory.
关键词： Sizing energy storage capacity,Empirical mode decomposition (EMD),Wavelet analysis,Photovoltaic output
更新于2025-09-12 10:27:22
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Voltage-assisted SILAR deposition of CdSe quantum dots into mesoporous TiO2 film for quantum dot-sensitized solar cells
摘要： CdSe quantum dots (QDs) grows slowly in mesoporous TiO2 film deriving from a large lattice mismatch (11 %) and poor interaction between the two, which resulting the low power conversion efficiency (PCE) of quantum dot-sensitized solar cells (QDSSCs). An external voltage is applied in the successive ionic layer adsorption reaction (SILAR) process, which drives the Cd2+ and SeSO3 2- ions quickly diffused into the mesoporous TiO2 film and reacted to form CdSe QDs at room temperature. The CdSe QDSSCs yields a PCE of 3.27%. This work provides an efficient strategy to assemble QDs for enhancing the performance of QDSSCs.
关键词： Electrodeposition,Semiconductors,Energy storage and conversion,Solar energy materials,Nanoparticles
更新于2025-09-11 14:15:04
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[IEEE 2019 IEEE Milan PowerTech - Milan, Italy (2019.6.23-2019.6.27)] 2019 IEEE Milan PowerTech - Stochastic optimization framework for online scheduling of an EV charging station in a residential place with photovoltaics and energy storage system
摘要： House and building energy management systems (HEMS) are becoming key when it comes to assure grid stability and to offer flexibility. At the same time, energy systems technology has evolved to enable energy storage systems and electric vehicles to be managed together with local generated energy taking into consideration the preferences of the household owner. Contributing to this tendency, this work presents a stochastic optimization platform (SOFW) for optimal control using dynamic programming and stochastic optimization models. A stochastic optimization model involving a household composed of photovoltaics, energy storage system and an electric vehicle is designed and tested within SOFW. The uncertainties of the plug-in time and state of charge of the battery of the electric vehicle are modeled using a Markovian process and a Monte-Carlo simulation. The results showed that the proposed stochastic optimization model can be solved using dynamic programming and deployed as a continuous optimal control within SOFW. The system will be deployed shortly in Italy within one use case of the Storage4Grid (S4G) project.
关键词： stochastic dynamic programming,optimization framework,energy storage systems,Markov processes,electric vehicle charging
更新于2025-09-11 14:15:04
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[IEEE 2019 IEEE Milan PowerTech - Milan, Italy (2019.6.23-2019.6.27)] 2019 IEEE Milan PowerTech - Optimal Scheduling of Generators and BESS using Forecasting in Power System with Extremely Large Photovoltaic Generation
摘要： Large scale integration of renewable energy sources (RES) can cause supply demand uncertainty. In Japanese power systems the photovoltaic (PV) generation is growing rapidly. PV forecasting with energy storage systems can be used in Unit Commitment (UC) to reduce these imbalances. In this study Battery Energy Storage systems (BESS) and day-ahead PV forecasting with prediction intervals have been used to examine the imbalances. The day-ahead UC of thermal generators and day-ahead optimal BESS charging and discharging is calculated with different BESS inverter capacities and BESS energy capacities. Then the power shortfall and surplus of PV power in the target day are calculated. The simulation is run for 3 months from April to June 2010 for Kanto area power system of Japan.
关键词： Photovoltaic (PV) forecasting,Unit Commitment (UC),Optimal Power dispatch,Battery Energy Storage Systems (BESS),Prediction Intervals,Mixed Integer Linear Programming (MILP)
更新于2025-09-11 14:15:04
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[IEEE 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Chengdu, China (2019.5.21-2019.5.24)] 2019 IEEE Innovative Smart Grid Technologies - Asia (ISGT Asia) - Development of Incentive Model for Photovoltaic Generators to Participate in a Day-ahead Electricity Market in South Korea
摘要： This paper presents the incentive model when Photovoltaic (PV) generator participates in a day-ahead market in South Korea. For this, the current supporting policy for PV generation and rules of a day-ahead market are analyzed. Because of the lack of the incentive model for PV supplier in a day-ahead market, Independent System Operation (ISO) can’t consider PV generation when they plan the short-term supply of the system. Therefore, the proposed incentive model is developed to provide the additional profit to encourage PV supplier to participate in the market based on the accuracy of PV generation bidding. To verify incentive model, the actual data including PV generation, System Marginal Price (SMP) and Renewable Energy Certificate (REC) price are used.
关键词： Day-ahead Electricity Market,Photovoltaic (PV),Energy Storage System (ESS),Incentive Model
更新于2025-09-11 14:15:04