共查询到20条相似文献,搜索用时 31 毫秒
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Masafumi Yamaguchi Tatsuya Takamoto Kenji Araki 《Solar Energy Materials & Solar Cells》2006,90(18-19):3068-3077
III–V compound multi-junction (MJ) (tandem) solar cells have the potential for achieving high conversion efficiencies of over 50% and are promising for space and terrestrial applications.We have proposed AlInP–InGaP double hetero (DH) structure top cell, wide-band gap InGaP DH structure tunnel junction for sub cell interconnection, and lattice-matched InGaAs middle cell. In 2004, we have successfully fabricated world-record efficiency concentrator InGaP/InGaAs/Ge 3-junction solar cells with an efficiency of 37.4% at 200-suns AM1.5 as a result of widening top cell band gap, current matching of sub cells, precise lattice matching of sub cell materials, proposal of InGaP–Ge heteroface bottom cell, and introduction of DH-structure tunnel junction. In addition, we have realized high-efficiency concentrator InGaP/InGaAs/Ge 3-junction solar cell modules (with area of 7000 cm2) with an out-door efficiency of 27% as a result of developing high-efficiency InGaP/InGaAs/Ge 3-junction cells, low optical loss Fresnel lens and homogenizers, and designing low thermal conductivity modules.Future prospects are also presented. We have proposed concentrator III–V compound MJ solar cells as the 3rd-generation solar cells in addition to 1st-generation crystalline Si solar cells and 2nd-generation thin-film solar cells. We are now challenging to develop low-cost and high output power concentrator MJ solar cell modules with an output power of 400 W/m2 for terrestrial applications and high-efficiency, light-weight and low-cost MJ solar cells for space applications. 相似文献
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该文采用Aspen Plus软件建立膜反应器重整制氢及燃料电池模型,根据拉萨某日太阳能直接辐射强度(DNI)变化计算太阳能可供使用的能量,作为外热源输入重整系统,并分析反应温度、水碳比(S/C)及DNI对该系统各性能指标的影响,性能指标包括甲烷转化率、H2收率、电池功率及电压、太阳能转换为氢能的效率。结果表明:反应温度为500 ℃,S/C为2.5时有利于太阳能甲烷湿重整反应;系统日性能结果显示在某日10:00—20:00时,电池输出功率120 kW,太阳能-化学能转化效率0.368,系统发电效率0.225。 相似文献
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为获取运动状态下太阳电池输出特性,提出一种基于多传感器信息融合的太阳电池动态建模方法。基于多传感器信息融合测量模型、欧式空间旋转理论、光照强度与太阳电池空间位置关系和太阳电池数学模型及其参数与光照强度之间耦合关系,构建太阳电池动态模型得到其动态输出特性。通过SIMPACK及Matlab/Simulink仿真软件建立太阳电池动态发电仿真平台验证了方法的有效性。结果表明,载体的运动明显影响了太阳电池输出特性,且在太阳电池输出最大功率点处的功率最大减少了18.038%。 相似文献
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Muhammad Badar Hayat Danish Ali Keitumetse Cathrine Monyake Lana Alagha Niaz Ahmed 《国际能源研究杂志》2019,43(3):1049-1067
Sun is an inexhaustible source of energy capable of fulfilling all the energy needs of humankind. The energy from the sun can be converted into electricity or used directly. Electricity can be generated from solar energy either directly using photovoltaic (PV) cells or indirectly using concentrated solar power (CSP) technology. Progress has been made to raise the efficiency of the PV solar cells that can now reach up to approximately 34.1% in multi‐junction PV cells. Electricity generation from concentrated solar technologies has a promising future as well, especially the CSP, because of its high capacity, efficiency, and energy storage capability. Solar energy also has direct application in agriculture primarily for water treatment and irrigation. Solar energy is being used to power the vehicles and for domestic purposes such as space heating and cooking. The most exciting possibility for solar energy is satellite power station that will be transmitting electrical energy from the solar panels in space to Earth via microwave beams. Solar energy has a bright future because of the technological advancement in this field and its environment‐friendly nature. The biggest challenge however facing the solar energy future is its unavailability all‐round the year, coupled with its high capital cost and scarcity of the materials for PV cells. These challenges can be met by developing an efficient energy storage system and developing cheap, efficient, and abundant PV solar cells. This article discusses the solar energy system as a whole and provides a comprehensive review on the direct and the indirect ways to produce electricity from solar energy and the direct uses of solar energy. The state‐of‐the‐art procedures being employed for PV characterization and performance rating have been summarized . Moreover, the technical, economic, environmental, and storage‐related challenges are discussed with possible solutions. Furthermore, a comprehensive list of future potential research directions in the field of direct and indirect electricity generation from solar energy is proposed. 相似文献
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为提高太阳电池转换效率,降低生产成本,分析太阳电池功率损失机制,建立非等宽主栅太阳电池总体相对功率损失模型。通过求解该模型得到太阳电池最佳前电极栅线形状尺寸参数。采用PC1D软件进行仿真分析得到太阳电池的光电转换效率,该结果与理论值匹配度较高;当主栅线数为2~6时,非等宽主栅结构太阳电池相比于典型的等宽栅线结构太阳电池,光电转换效率分别提高了0.10%、0.09%、0.10%、0.09%和0.09%;主栅线总体积分别减少了0.72、0.68、0.64、0.58和0.47 mm3;细栅线总体积的增加量不超过0.07 mm3。表明非等主栅前电极栅线结构不仅提高了光电转换效率,也降低了银浆的使用量。 相似文献
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We investigated multistacked solar cells with a structure of metal/a-si: H (n-i-p)/poly-Si (n-p)/metal. This cell consists of two component cells; top n-i-p junction a-Si : H cell and a bottom n-p junction poly-Si cell. The solar cell conversion influencing factors were investigated in terms of film thickness, doping concentration, minority carrier lifetime, diffusion length, surface recombination, surface potential, AR coating, and circuit parameters of solar cells. The optimization of material and solar cell was carried out by using a PC-1D simulator. The main stream lines of the studies were the p-n junction poly-Si bottom cell, the p-i-n junction top a-Si : H cell, and the equivalent circuit examination. The optimized simulation results indicates that the 22% efficiency of multistacked solar cells can be achieved by optimizing parameters in each layer. 相似文献
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该文定量研究电子和质子辐射对太阳电池输出特性的影响。首先,证实作者前期工作得到的太阳电池输出电流-电压(I-V)模型仍适用于高能粒子辐射后的太阳电池;其次,由太阳电池输出电流-电压特征量定义一个等效电阻(R eq )。采用最小二乘方曲线拟合方法,找到能够定量描述太阳电池能量转化效率(PCE)与等效电阻(R eq )的关系,并且定量解释了经历电子和质子辐照的太阳电池的等效电阻(R eq )同辐照剂量的关系。最后,扩展这个模型用于定量描述太阳电池外量子效率(EQE )与入射光子能量(hν )的关系,经拟合验证,该模型与实验数据十分吻合,理论同实验结果的相关系数R 大于0.98,平均相对误差(ARE )小于3%。 相似文献
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Alaa A. Zaky Mohamed N. Ibrahim Hegazy Rezk Eleftherios Christopoulos Ragab A. El Sehiemy Evangelos Hristoforou Antonios Kladas Peter Sergeant Polycarpos Falaras 《国际能源研究杂志》2020,44(14):11629-11642
Perovskite solar cells (PSCs) are in the forefront of third-generation of photovoltaics and gained a lot of attention as a very promising green technology toward direct solar energy conversion to electricity. PSCs are fabricated following solution-processed techniques at low temperature and they present high power conversion efficiency exceeding 25%, enabling them to be attractive alternative to the silicon-based devices. This research work proposes an efficient and cost-effective photovoltaic (PV) pumping system based on PSCs. For this purpose, lab-scale PSCs were fabricated and their characteristics were determined. In parallel, the geometry of a synchronous reluctance motor (SynRM) driving a 350 m3/day water pump was optimized for maximizing the output power, while minimizing the torque ripple simultaneously. In addition, a perovskite solar array feeding the SynRM via an inverter was designed and implemented. The inverter was properly regulated by a control system which optimized the maximum available power of the PSCs solar array and the SynRM characteristics. Finally, laboratory measurements were performed, including a power generator simulating the behavior of the PSCs array feeding the SynRM. The obtained results confirmed the experimental validation of the proposed approach. 相似文献
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Although efficiency of photovoltaic (PV) modules is usually specified under standard test conditions (STC), their operation under real field conditions is of great importance for obtaining accurate prediction of their efficiency and power output. The PV conversion process, on top of the instantaneous solar radiation, depends also on the modules' temperature. Module temperature is in turn influenced by climate conditions as well as by the technical characteristics of the PV panels. Taking into consideration the extended theoretical background in the field so far, the current study is focused on the investigation of the temperature variation effect on the operation of commercial PV applications based on in-situ measurements at varying weather conditions. Particularly, one year outdoor data for two existing commercial (m-Si) PV systems operated in South Greece, i.e. an unventilated building-integrated (81 kWp) one and an open rack mounted (150 kWp) one, were collected and evaluated. The examined PV systems were equipped with back surface temperature sensors in order to determine module and ambient temperatures, while real wind speed measurements were also obtained for assessing the dominant effect of local wind speed on the PVs' thermal loss mechanisms. According to the results obtained, the efficiency (or power) temperature coefficient has been found negative, taking absolute values between 0.30%/°C and 0.45%/°C, with the lower values corresponding to the ventilated free-standing frames. 相似文献
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在构建系统集成模型的基础上,阐述光煤混合发电系统变工况性能计算方法。以3个地区和4种容量燃煤机组为例,研究集成模型、取代份额、辐射强度、地区和容量对光煤混合发电系统性能的影响规律。结果表明:机组容量和地区一定的情况下,全部取代1级抽汽且辐射强度最大时的系统节能效果最优;同机组不同地区开展混合发电时,太阳能资源丰富地的集热场面积最小,集热场换热效率和太阳能热电转换效率最大,年累计节能减排量大,静态投资回收期最短;同地区不同容量机组开展混合发电时,大容量机组年平均太阳能热电转换效率和年累计节能减排量最大,静态投资回收期最短。 相似文献
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The output power prediction by a photovoltaic (PV) system is an important research area for which different techniques have been used. Solar cell modeling is one of the most used methods for power prediction, the accuracy of which strongly depends on the selection of cell parameters. In this study, a new integrated single‐diode solar cell model based on three, four, and five solar cell parameters is developed for the prediction of PV power generation. The experimental validation of the predicted results is done under outdoor climatic conditions for an Indian location. The predicted power by three models is found close to measured values within 4.29% to 4.76% accuracy range. The comparative power estimation analysis by these models shows that the three‐parameter model gives higher accuracy for low solar irradiance values <150 W/m2, the four‐parameter model in the range of 150 to 500 W/m2, and the five‐parameter model for >500 W/m2. The present model is also compared with other models in literature and is found to be more accurate with less percentage error. The overall results also show that the power produced depends on temperature and solar radiation levels at a particular location. Thus, single solar cell model developed can be used with sufficient accuracy for power forecast of PV systems for any location worldwide. The follow‐up research areas are also identified. 相似文献
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Shin'ya Obara 《国际能源研究杂志》2010,34(7):594-608
In this research, the development of a bioethanol reforming system for fuel cells (FBSR: fuel cell with bioethanol steam reforming) using sunlight as a heat source was investigated. The system was investigated using the experimental result of catalyst performance, and numerical analysis. If ethanol purity is high, the production method of the bioethanol used for the proposal system will not be limited. The overall efficiency of the production of electricity and heat power of this system was determined by examining its thermal output characteristic. The FBSR was introduced into standard individual houses in Sapporo, Japan, for analysis. The amount of hydrogen production, the production‐of‐electricity characteristic, and the thermal output characteristic were examined using meteorological data on representative days in March and August. Compared with the representative day in March (28.0 MJ day−1), the solar radiation of the representative day in August (37.0 MJ day−1) is large. However, the amount of solar radiation fluctuation of the representative day in August in this analysis is large compared with the representative day in March. It depends for the overall efficiency of the system on the amount of solar radiation fluctuation rather than the amount of solar radiation. As a result, the overall efficiency of the system, defined as the rate of power and heat output compared with the amount of solar heat collected, was calculated to be 47.4 and 41.9% on the representative days in March and August, respectively. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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太阳烟囱发电系统及其固有的热力学不完善性分析 总被引:12,自引:4,他引:12
简述了太阳烟囱发电系统的工作原理,指出根据浮力产生的压强差的不同计算方法将得到不同的性能评价。基于这种发电系统的创始人Schliach给出的一个30MW的算例,计算了太阳集热棚和烟囱组合的第一定律效率及集热棚和烟囱各自的第二定律效率。说明太阳烟囱发电技术实质上是太阳热发电,受热力学定律的制约。虽然太阳集热棚的效率相当高,但其第二定律效极低,比第一定律效率低一个量级。由于作为热发电系统热源的热空气的温度很低,这就导致了即使在理想的条件下系统的发电效率也较难大于1% 相似文献
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Concentrating solar thermal power and photovoltaics are two major technologies for converting sunlight to electricity. Variations of the annual solar irradiation depending on the site influence their annual efficiency, specific output and electricity generation cost. Detailed technical and economical analyses performed with computer simulations point out differences of solar thermal parabolic trough power plants, non-tracked and two-axis-tracked PV systems. Therefore, 61 sites in Europe and North Africa covering a global annual irradiation range from 923 to 2438 kW h/m2 a have been examined. Simulation results are usable irradiation by the systems, specific annual system output and levelled electricity cost. Cost assumptions are made for today's cost and expected cost in 10 years considering different progress ratios. This will lead to a cost reduction by 50% for PV systems and by 40% for solar thermal power plants. The simulation results show where are optimal regions for installing solar thermal trough and tracked PV systems in comparison to non-tracked PV. For low irradiation values the annual output of solar thermal systems is much lower than of PV systems. On the other hand, for high irradiations solar thermal systems provide the best-cost solution even when considering higher cost reduction factors for PV in the next decade. Electricity generation cost much below 10 Eurocents per kW h for solar thermal systems and about 12 Eurocents/kW h for PV can be expected in 10 years in North Africa. 相似文献