Solar Energy最新文献_第7页

Energy, exergy, and economic analysis of a novel solar-assisted ejector subcooling CO2 transcritical refrigeration systemt 新型太阳能辅助喷射器过冷二氧化碳跨临界制冷系统的能量、放能和经济分析t

IF 6 2区工程技术 Q2 ENERGY & FUELS

Solar Energy

Pub Date : 2024-11-07 DOI: 10.1016/j.solener.2024.113080

Tailan Yin, Qichao Yang, Jiawei Jiang, Zeye Zheng, Yuanyang Zhao, Guangbin Liu, Liansheng Li

To further enhance the performance of transcritical CO₂ refrigeration cycle (base cycle), a solar-assisted ejector subcooling transcritical CO₂ refrigeration cycle (SESRS) is proposed. The base cycle is subcooled utilizing a solar-assisted ejector refrigeration cycle. This research performed energy, exergy, and economic evaluations of SESRS utilizing the eco-friendly refrigerant R152a in the ejector cycle based on the established model. The thermodynamic analysis results demonstrate that SESRS outperform the base cycle. At typical working conditions, the COP_m of the SESRS demonstrates a 22.96 % increase compared to that of the base cycle. Although the total cost of the SESRS is 7.98 %–17.9 % higher than that of the base cycle when subcooling degree is 5 °C, the enhancement of COP_m is larger and is increased by approximately 18.34 %–26.22 %. The impact of subcooling degree and other parameters on system performance are also investigated. Overall, this study confirms the potential of the SESRS system for utilization in the refrigeration and air-conditioning fields. Considering both the system’s performance and economy, further optimized analysis should be done on key operational parameters, such as subcooling degree and discharge pressure.

为了进一步提高跨临界二氧化碳制冷循环（基础循环）的性能，提出了一种太阳能辅助喷射器过冷跨临界二氧化碳制冷循环（SESRS）。基础循环利用太阳能辅助喷射器制冷循环进行过冷。该研究基于已建立的模型，对在喷射器循环中使用环保制冷剂 R152a 的 SESRS 进行了能量、放能和经济评估。热力学分析结果表明，SESRS 的性能优于基本循环。在典型工况下，SESRS 的 COPm 比基本循环提高了 22.96%。虽然当过冷度为 5 °C 时，SESRS 的总成本比基本循环高 7.98 %-17.9 %，但 COPm 的提高幅度更大，提高了约 18.34 %-26.22 %。此外，还研究了过冷度和其他参数对系统性能的影响。总之，这项研究证实了 SESRS 系统在制冷和空调领域的应用潜力。考虑到系统的性能和经济性，应进一步对过冷度和排放压力等关键运行参数进行优化分析。

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引用次数: 0

Competitive influence of interface effect, scale effect and mixed salt ratio on thermal conductivity of mesoporous complex nitrate 界面效应、尺度效应和混合盐比例对介孔复合硝酸盐导热性的竞争影响

IF 6 2区工程技术 Q2 ENERGY & FUELS

Solar Energy

Pub Date : 2024-11-06 DOI: 10.1016/j.solener.2024.113075

Shuang Ma , Chenxuan Yan , Liqin He , Qirong Yang , Zhaoying Li , Xinsong Wang , Han Jiang , Youping Li

The rising prominence of energy security and climate change issues necessitates the advancement of sustainable energy development and energy storage technologies. Enhancing the capabilities of mesoporous composite phase change materials (CPCMs) has gained considerable research interest. CPCM’s heat storage and release performance is largely determined by its thermal conductivity. While the existing literature has documented the individual effects of the composition ratio of mixed molten salts, scale effects, and interfacial effects on thermal conductivity, no studies have been found that investigate the competitive interplay among these three factors with respect to their impact on thermal conductivity. This study aims to gain a deeper insight into the thermal conductivity changes of CPCM consisting of mixed molten salts as the phase change material (PCM) and mesoporous skeleton. A combination of molecular dynamics simulations and experimental investigations was employed to explore how interface effects, scale effects, and the proportion of mixed salts contribute to the thermal conductivity of CPCM. The findings indicate that augmented thermal conductivity, resulting from interface effects, supersedes the diminishing effects of interionic interactions. Compared to mixed salt ratios, interface effects primarily result in variations in the thermal conductivity of CPCM. The thermal conductivity of mixed nitrates escalates alongside scale increases. In the 3–4 nm range, the scale effect and mixed nitrate proportions do not notably compete in terms of influence on thermal conductivity, interface effects are more profound than scale effects. In the 4–9.5 nm range, the scale effect is more profound than mixed nitrate ratios. If the skeleton transitions from SiO₂ to Al₂O₃, the impact of the interface effect on thermal conductivity is greater influential than the scale effect. While transitioning the interface from Al₂O₃ to ceramic, the effect of the interface is less than or equal to that of the scale effect on the thermal conductivity.

随着能源安全和气候变化问题的日益突出，有必要推进可持续能源开发和能源储存技术。提高介孔复合相变材料（CPCMs）的性能已引起了广泛的研究兴趣。CPCM 的热存储和释放性能在很大程度上取决于其热导率。虽然现有文献已记录了混合熔盐的成分比、规模效应和界面效应对热导率的单独影响，但尚未发现研究这三个因素之间的竞争性相互作用对热导率的影响。本研究旨在深入了解由混合熔盐作为相变材料（PCM）和介孔骨架组成的 CPCM 的热导率变化。研究结合分子动力学模拟和实验研究，探讨了界面效应、尺度效应和混合盐比例对 CPCM 热导率的影响。研究结果表明，界面效应所产生的热导率增强效应取代了离子间相互作用的递减效应。与混合盐比率相比，界面效应主要导致 CPCM 导热率的变化。混合硝酸盐的热导率会随着尺度的增加而增加。在 3-4 纳米范围内，鳞片效应和混合硝酸盐比例对热导率的影响并不明显，界面效应比鳞片效应更为显著。在 4-9.5 纳米范围内，鳞片效应比混合硝酸盐比例的影响更大。如果骨架从 SiO2 过渡到 Al2O3，则界面效应对热导率的影响比刻度效应更大。当界面从 Al2O3 过渡到陶瓷时，界面效应对热导率的影响小于或等于鳞片效应对热导率的影响。

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引用次数: 0

Analysis of an ultra-broadband TiN-based metasurface absorber for solar thermophotovoltaic cell in the visible to near infrared region 分析可见光至近红外区域太阳能热光电池的超宽带 TiN 基元表面吸收器

IF 6 2区工程技术 Q2 ENERGY & FUELS

Solar Energy

Pub Date : 2024-11-06 DOI: 10.1016/j.solener.2024.113064

Mohammad Ashraful Haque, Abu S.M. Mohsin, Mohammed Belal Hossain Bhuian, Md Mosaddequr Rahman

Solar thermophotovoltaic (STPV) represents next-generation technology for solar cells, enabling higher efficiency and better performance through advanced photothermal processes. They can surpass the Shockley–Queisser limit due to their superior photothermal conversion efficiency. The absorber is a crucial component on which the efficiency of the entire system depends. In this article, we have proposed a TiN-based metasurface absorber (MA) which is capable of operating at high temperatures with superior efficiency. We have numerically investigated the structure using the Finite Difference Time Domain (FDTD) method. Our analysis suggests that the MA can absorb more than 90% radiation in the 200–1733.5 nm range and achieves near-perfect absorbance (more than 99.5%) in the 719.7 - 1371 nm range which is suitable for solar cell applications. Moreover, the MA also emits selective radiation and works as a metasurface emitter (ME). It achieves a maximum photothermal efficiency of 80% at 1900 K temperature. The findings of this study opens a new avenue for the development of cost effective, reliable and stable, highly efficient solar thermophotovoltaic cells in the visible to near infrared region.

太阳能光热发电（STPV）是太阳能电池的新一代技术，通过先进的光热工艺实现更高的效率和更好的性能。由于其卓越的光热转换效率，它们可以超越肖克利-奎塞尔极限。吸收器是整个系统效率的关键部件。在本文中，我们提出了一种基于 TiN 的超表面吸收器 (MA)，这种吸收器能够在高温下工作，并具有卓越的效率。我们使用有限差分时域 (FDTD) 方法对该结构进行了数值研究。我们的分析表明，超表面吸收器在 200-1733.5 nm 波长范围内可吸收 90% 以上的辐射，在 719.7 - 1371 nm 波长范围内可达到接近完美的吸收率（99.5% 以上），适合太阳能电池应用。此外，MA 还能发出选择性辐射，可用作超表面发射器（ME）。在 1900 K 的温度下，它的最大光热效率可达 80%。这项研究的发现为在可见光到近红外区域开发经济、可靠、稳定、高效的太阳能光热发电电池开辟了一条新途径。

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引用次数: 0

Wind loads on heliostat tracker: A LES study on the role of geometrical details and the characteristics of near-ground turbulence 定日镜跟踪器上的风载荷：关于几何细节的作用和近地湍流特性的 LES 研究

IF 6 2区工程技术 Q2 ENERGY & FUELS

Solar Energy

Pub Date : 2024-11-05 DOI: 10.1016/j.solener.2024.113041

Weilin Li , Fa Yang , Huawei Niu , Luca Patruno , Xugang Hua

The accurate evaluation of the operational and survival wind loads for ground-mounted heliostat trackers is vital for reducing the total cost during the life cycle of concentrated solar power plants. Current studies rely on reduced scale Wind Tunnel Tests (WTTs), which makes the investigation of the effects of supporting components and near-ground turbulence not trivial. As a result, there is an urgent need to develop complementary techniques to guide wind-resistant designs of commercial heliostats. In this paper, we investigate the performance of Large Eddy Simulations (LES) to systematically study the mean and peak wind loads over heliostats. The effects of elevation and azimuth angles, supports components, turbulence intensity and length scale are investigated. Results show that the proposed LES model accurately reproduces integral force coefficients and the local pressure distributions. Further, an accurate evaluation of the survival wind loads needs to consider the effects of supports components, as they contribute more than 50% to the mean lift and overturning moment in the stow positions. Finally, the effects of turbulence intensity and integral scale are clarified by considering eight different combinations of parameters to characterize the near-ground turbulence. This study provides useful guidelines for design wind loads and lays a solid foundation for LES of heliostat arrays.

准确评估地面定日镜跟踪器的运行和生存风载荷对于降低聚光太阳能发电站生命周期内的总成本至关重要。目前的研究依赖于小规模风洞试验（WTTs），这使得对支撑组件和近地湍流影响的研究变得非常困难。因此，迫切需要开发辅助技术来指导商用定日镜的抗风设计。在本文中，我们研究了大涡流模拟（LES）的性能，以系统地研究定日镜上的平均风荷载和峰值风荷载。研究了仰角和方位角、支持成分、湍流强度和长度尺度的影响。结果表明，所提出的 LES 模型准确地再现了积分力系数和局部压力分布。此外，对生存风荷载的准确评估需要考虑支架部件的影响，因为它们对收放位置的平均升力和倾覆力矩的贡献超过 50%。最后，通过考虑八种不同的参数组合来描述近地湍流的特征，澄清了湍流强度和积分尺度的影响。这项研究为设计风载荷提供了有用的指导，并为定日镜阵列的 LES 奠定了坚实的基础。

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引用次数: 0

Interfacial evaporation characteristics of three-dimensional Cu-Fe3O4 nanoparticle film 三维 Cu-Fe3O4 纳米粒子薄膜的界面蒸发特性

IF 6 2区工程技术 Q2 ENERGY & FUELS

Solar Energy

Pub Date : 2024-11-04 DOI: 10.1016/j.solener.2024.113071

Maoqing Tang, Cong Qi, Linfei Yue, Zhanpeng Yu

In an effort to further enhance the evaporation effect of interfacial evaporation, a super-hydrophilic nanoparticle film was prepared by ultrasonic impregnation in this paper. Then, by improving the structure and configuration design of nanoparticle film, the nanoparticle film was transformed from two-dimensional structure to three-dimensional structure. The effects of three-dimensional structure shape, radiation intensity and three-dimensional structure height on the evaporation capacity of nanoparticle films were studied. It was found that the evaporation rate of the three-dimensional rectangular Cu-Fe₃O₄ nanoparticle film with a rectangular height of 15 mm achieved 1.2 kg/m²/h under one sun radiation intensity. The evaporation efficiency can reach 75.44 %, and the thermal efficiency can reach 111.91 %. The design of the three-dimensional structure enables the nanoparticle film to perform double-sided evaporation. At the same time, under the action of natural air convection, the nanoparticle film evaporation efficiency is greatly improved, which provides a design strategy for the nanoparticle film in the field of solar-driven interface evaporation.

为了进一步提高界面蒸发的蒸发效果，本文采用超声浸渍法制备了超亲水性纳米粒子膜。然后，通过改进纳米粒子膜的结构和构型设计，将纳米粒子膜从二维结构转变为三维结构。研究了三维结构形状、辐射强度和三维结构高度对纳米粒子薄膜蒸发能力的影响。研究发现，在一个太阳辐射强度下，矩形高度为 15 mm 的三维矩形 Cu-Fe3O4 纳米粒子薄膜的蒸发率达到 1.2 kg/m2/h。蒸发效率达到 75.44 %，热效率达到 111.91 %。三维结构的设计使纳米颗粒薄膜可以进行双面蒸发。同时，在自然空气对流的作用下，纳米粒子薄膜的蒸发效率大大提高，这为纳米粒子薄膜在太阳能驱动的界面蒸发领域提供了一种设计策略。

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引用次数: 0

Effects of dust and rainfall on the relative reflectivity of linear Fresnel reflectors 灰尘和降雨对菲涅尔线性反射镜相对反射率的影响

IF 6 2区工程技术 Q2 ENERGY & FUELS

Solar Energy

Pub Date : 2024-11-04 DOI: 10.1016/j.solener.2024.113065

Xiaoyan Zhao, Rong Cheng, Yahui Wang, Yiwei Fu, Jialin Guo

Dust and rainfall have been key issues affecting outdoor solar concentrating systems. This study aimed to accurately evaluate the specific effects of dust and rainfall on linear Fresnel reflectors in semi-arid regions. Targeted outdoor experiments on dust and rainwater were conducted in Hohhot, Inner Mongolia, from September to December 2023. A predictive model is developed to assess the effect of rainfall on reflectivity under conditions of dust accumulation, based on the physical properties of outdoor-exposed dust. The study reveals that after 60 days of exposure, the reflectivity decreased at a rate of 0.25 % per day due to mirror dust, particularly within the 380–780 nm wavelength range, reaching 21.62 %. The rainfall leads to four distinct conditions, namely pitting, surface corrosion, gully corrosion, and overall corrosion on the dusty mirror. During the gully corrosion and corrosion stages, the reflectivity significantly improved. Rainfall below 0.4 mm barely cleaned mirror dust, whereas rainfall exceeding 26.70 mm provided substantial cleaning but reached a saturation point with additional rainfall. These findings contribute to the development of cost-effective cleaning strategies for similar climatic conditions.

灰尘和降雨一直是影响室外太阳能聚光系统的关键问题。本研究旨在准确评估灰尘和降雨对半干旱地区线性菲涅尔反射镜的具体影响。2023 年 9 月至 12 月，在内蒙古呼和浩特市进行了有针对性的灰尘和雨水室外实验。根据室外暴露灰尘的物理性质，建立了一个预测模型，以评估灰尘积累条件下降雨对反射率的影响。研究结果表明，在暴露 60 天后，反射率因镜面灰尘以每天 0.25 % 的速度下降，尤其是在 380-780 nm 波长范围内，达到 21.62 %。降雨导致了四种不同的情况，即点蚀、表面腐蚀、沟槽腐蚀和含尘反射镜的整体腐蚀。在沟蚀和腐蚀阶段，反射率明显提高。低于 0.4 毫米的降雨量几乎不能清洁镜面灰尘，而超过 26.70 毫米的降雨量则能提供大量清洁，但随着降雨量的增加达到饱和点。这些发现有助于在类似气候条件下开发具有成本效益的清洁策略。

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引用次数: 0

Evaluating the electronic and structural basis of carbon selenide-based quantum dots as photovoltaic design materials: A DFT and ML analysis 评估作为光伏设计材料的硒化碳基量子点的电子和结构基础：DFT 和 ML 分析

IF 6 2区工程技术 Q2 ENERGY & FUELS

Solar Energy

Pub Date : 2024-11-04 DOI: 10.1016/j.solener.2024.113068

Afaf M. Kadhum , Azal S. Waheeb , Masar A. Awad , Abrar U. Hassan , Sajjad H. Sumrra , Cihat Güleryüz , Ayesha Mohyuddin , Sadaf Noreen , Hussein A.K. Kyhoiesh , Mohammed T. Alotaibi

We present a new study on the design, discovery and space generation of carbon selenide based photovoltaic (PV) materials. By extending acceptors and leveraging density functional theory (DFT) and machine learning (ML) analysis, we discover new QDs with remarkable PV properties. We employ various ML models, to correlate the exciton binding energy (E_b) of 938 relevant compounds from literature with their molecular descriptors of structural features that influence their performance. Our study demonstrates the potential of ML approaches in streamlining the design and discovery of high-efficiency PV materials. Also the RDKit computed molecular descriptors correlates with PV parameters revealed maximum absorption (λ_max) ranges of 509–531 nm, light harvesting efficiency (LHE) above 92 %, Open Circuit Voltage (V_oc) of 0.22–0.45 V, and short Circuit (J_sc) currents of 37.92–42.75 mA/cm². Their Predicted Power Conversion Efficiencies (PCE) using the Scharber method reaches upto 09–13 %. This study can pave the way for molecular descriptor-based design of new PV materials, promising a paradigm shift in the development of high-efficiency solar energy conversion technologies.

我们对基于硒化碳的光伏（PV）材料的设计、发现和空间生成进行了一项新的研究。通过扩展受体并利用密度泛函理论（DFT）和机器学习（ML）分析，我们发现了具有显著光伏特性的新型 QDs。我们采用各种 ML 模型，将文献中 938 种相关化合物的激子结合能 (Eb) 与影响其性能的分子结构特征描述相关联。我们的研究证明了 ML 方法在简化设计和发现高效光伏材料方面的潜力。此外，RDKit 计算出的分子描述符与光伏参数的相关性显示，最大吸收（λmax）范围为 509-531 nm，光收集效率（LHE）高于 92%，开路电压（Voc）为 0.22-0.45 V，短路电流（Jsc）为 37.92-42.75 mA/cm2。利用夏伯法预测的功率转换效率（PCE）高达 09-13%。这项研究为基于分子描述符设计新型光伏材料铺平了道路，有望推动高效太阳能转换技术的发展模式转变。

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引用次数: 0

Effects of insert design and optimization on the performance of parabolic trough receivers with inserted absorbers 插入式设计和优化对带有插入式吸收器的抛物槽接收器性能的影响

IF 6 2区工程技术 Q2 ENERGY & FUELS

Solar Energy

Pub Date : 2024-11-02 DOI: 10.1016/j.solener.2024.113061

Jiangbo Wang , Liangcai Zeng , Sheng Yu , Yuting He

To address the non-uniform heat flux density characteristics of parabolic trough solar collectors (PTSCs), an innovative insert (composed of vortex generator, VG) layout scheme is introduced in this study. Under turbulent conditions, an analysis is conducted on the thermal performance of three different placement strategies (uniform distribution, UD, directional distribution-1, DD-1, and directional distribution-2, DD-2), including the calculation of Nusselt numbers, drag coefficients, and thermal enhancement factors. The results indicate that VG can induce paired vortices, and the position, intensity, and quantity of vortices are closely related to the shape of VG. Based on the direction of vortex flow, the flow field is divided into collision area (CA) and pushing area (PA). In the CA, vortices collide with each other, consuming turbulent energy and reducing local heat transfer efficiency. In the PA, the direction of vortice motion is opposite, which can achieve efficient local heat efficiency. In the three VG cases, the DD-2 configuration can induce non-uniformly distributed high-intensity mixed vortices and further achieve the demand for heat transfer enhancement in the area of high heat flux density through the ejection and sweeping movements of these vortices. In all investigations, DD-2 configuration can achieve an improvement in heat transfer rate ranging from 1.5 to 2.12. In terms of heat transfer performance (

ψ

), the ψ value of DD-2 is 1.37 at N = 4 and Re = 20,000. Besides, the thermal performance of the tube with insert is analyzed through entropy generation.

针对抛物面槽式太阳能集热器（PTSC）热通量密度不均匀的特点，本研究引入了一种创新的插入式（由涡流发生器组成，VG）布置方案。在湍流条件下，对三种不同布置策略（均匀分布，UD；定向分布-1，DD-1；定向分布-2，DD-2）的热性能进行了分析，包括努塞尔特数、阻力系数和热增强因子的计算。结果表明，VG 可诱发成对涡流，涡流的位置、强度和数量与 VG 的形状密切相关。根据涡流的流动方向，流场被分为碰撞区（CA）和推动区（PA）。在碰撞区，涡流相互碰撞，消耗湍流能量，降低局部传热效率。而在 PA 区，涡流运动方向相反，可以实现高效的局部热效率。在三种 VG 情况下，DD-2 配置可诱导非均匀分布的高强度混合涡流，并通过这些涡流的喷射和横扫运动进一步实现高热流密度区域的传热增强需求。在所有研究中，DD-2 配置可实现 1.5 至 2.12 的传热率改进。就传热性能（ψ）而言，在 N = 4 和 Re = 20,000 条件下，DD-2 的ψ值为 1.37。此外，我们还通过熵的产生分析了带内衬管的热性能。

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引用次数: 0

Study on energy and exergy performance of a new hybrid perforated photovoltaic/solar air heater integrated with encapsulated phase change materials: An experimental study 研究一种集成了封装相变材料的新型混合穿孔光伏/太阳能空气加热器的能量和能效性能：实验研究

IF 6 2区工程技术 Q2 ENERGY & FUELS

Solar Energy

Pub Date : 2024-11-02 DOI: 10.1016/j.solener.2024.113062

Hadi Farzan , Mojtaba Mahmoudi , Omid Moradnejad , Forouzesh Rafiei Rezvani

The current study conducts energy and exergy analyses on an innovative hybrid perforated photovoltaic/solar air heater (PV/SAH) using passive and active methods to improve thermal and electrical efficiencies. Since increasing PVs’ temperature reduces their electrical efficiency, various techniques have been employed to handle this problem, employing effective cooling strategies. This study uses an experimental approach to analyze two cooling strategies: encapsulated phase change material (PCM) units as a passive method and forced-convection mechanism as an active method. Two scenarios were considered: hybrid PV/SAH with and without encapsulated PCM units at two mass flow rates of 0.05 kg/s and 0.07 kg/s. The results illustrate that the encapsulated PCM reduced the PV and outlet temperatures by 2 °C and 4 °C, and 3 °C and 1.5 °C at the mass flow rates of 0.05 kg/s and 0.07 kg/s, respectively. The lower the outlet temperature, the lower the thermal efficiency. Hence, using the PCM units decreased the thermal efficiency but improved the electrical efficiency. The PCM units caused a reduction in daily overall energy efficiency by 12.41 % and 8.36 % at the mass flow rates of 0.05 kg/s and 0.07 kg/s due to reducing thermal efficiency. Unlike the energy efficiency, the PCM units improved the daily overall exergy efficiency by 6.28 % and 8.71 % at the mass flow rates considered. Hence, using passive and active methods is a robust technique to improve the hybrid systems’ performance.

本研究采用被动和主动方法，对创新型混合穿孔光伏/太阳能空气加热器（PV/SAH）进行了能量和放能分析，以提高热效率和电效率。由于光伏的温度升高会降低其电气效率，因此人们采用了各种技术来解决这一问题，并采用了有效的冷却策略。本研究采用实验方法分析了两种冷却策略：作为被动方法的封装相变材料 (PCM) 单元和作为主动方法的强制对流机制。研究考虑了两种情况：在 0.05 千克/秒和 0.07 千克/秒两种质量流量条件下，使用和不使用封装相变材料单元的混合光伏/太阳能。结果表明，在 0.05 千克/秒和 0.07 千克/秒的质量流量下，封装 PCM 分别将光伏和出口温度降低了 2 ℃ 和 4 ℃，以及 3 ℃ 和 1.5 ℃。出口温度越低，热效率越低。因此，使用 PCM 设备降低了热效率，但提高了电效率。在质量流量为 0.05 千克/秒和 0.07 千克/秒时，由于热效率降低，PCM 单元导致日总能效分别降低了 12.41% 和 8.36%。与能效不同的是，在考虑的质量流量条件下，PCM 设备的日总体放能效分别提高了 6.28 % 和 8.71 %。因此，使用被动和主动方法是提高混合动力系统性能的可靠技术。

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引用次数: 0

Deciphering hysteresis in perovskite solar cells: Insights from device simulations distinguishing shallow traps from mobile ions 解读过氧化物太阳能电池中的滞后现象：从区分浅陷阱和移动离子的器件模拟中获得启示

IF 6 2区工程技术 Q2 ENERGY & FUELS

Solar Energy

Pub Date : 2024-11-02 DOI: 10.1016/j.solener.2024.113037

Welmoed Veurman , Jonas Kern , Leon Pflüger , Hannes Wagner-Mohnsen , Matthias Müller , Pietro P. Altermatt , ZhaoYu Lou , Martin Stolterfoht , Felix Haase , Sarah Kajari-Schröder , Robby Peibst

In perovskite solar cells, a hysteresis of the current–voltage curve is often observed and is usually attributed to moving ions. However, our device modelling forecasts that it can also be explained, at least in part, by the occupation behaviour of slow-shallow trap states in the perovskite material. A difference between the ionic and trap interpretation arises in the illumination dependence of the hysteresis. Under the assumption of slow-shallow trap states, our simulations show that a diffusion capacitive effect should be observed at high scanning rates (> 100 V/s) and low light intensities (< 0.01 sun). This effect does not appear when assuming a device model with moving ion vacancies. This offers an opportunity for experimentally distinguishing between the two explanatory models and to quantify the relative contributions to hysteresis from ion vacancies and traps, respectively.

在过氧化物太阳能电池中，经常会观察到电流-电压曲线的滞后现象，通常将其归因于移动离子。然而，我们的设备建模预测，这种现象也可以用包晶石材料中慢-浅阱态的占据行为来解释，至少部分是这样。离子解释和陷阱解释的区别在于滞后的光照依赖性。根据慢浅阱态的假设，我们的模拟结果表明，在高扫描速率（> 100 V/s）和低光照强度（< 0.01 sun）条件下，应能观察到扩散电容效应。在假设具有移动离子空位的器件模型时，这种效应不会出现。这为通过实验区分这两种解释模型以及量化离子空位和陷阱对滞后的相对贡献提供了机会。

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引用次数: 0