薄膜太阳能电池在荒漠电站的应用前景分析

以内蒙古阿左旗某MWp级并网太阳能光伏发电工程为例,通过对相同容量多晶硅和非晶硅/微晶硅薄膜光伏发电单元在发电量、占地面积、初投资等方面的比较,得出在荒漠地区建设大型并网光伏电站,非晶硅/微晶硅薄膜电池的综合经济效益优于多晶硅的结论。认为非晶硅薄膜电池在我国大型并网光伏发电领域应用前景广阔,发展潜力巨大。     

薄膜太阳能电池在荒漠电站的应用前景分析

以内蒙古阿左旗某MWp级并网太阳能光伏发电工程为例,通过对相同容量多晶硅和非晶硅/微晶硅薄膜光伏发电单元在发电量、占地面积、初投资等方面的比较,得出在荒漠地区建设大型并网光伏电站,非晶硅/微晶硅薄膜电池的综合经济效益优于多晶硅的结论.认为非晶硅薄膜电池在我国大型并网光伏发电领域应用前景广阔,发展潜力巨大.     

中间层厚度对具有隧穿结构的叠层电池的影响

为了提高非晶硅/微晶硅叠层电池的转换效率和稳定性,在隧穿结构中引入ZnO:B中间层,研究了中间层厚度对叠层电池短路电流密度、开路电压、转换效率等性能的影响。实验结果表明,较薄的中间层厚度,可以优化顶电池和底电池的短路电流密度,使微晶硅底电池生长致密,提高叠层电池的开路电压。采用厚度为60 nm的中间层,并优化顶电池和底电池的厚度后,制备出了初始转换效率为11.5%、衰退率在9%以内的叠层电池。     

高效率非晶硅叠层太阳电池的研制

深入研究了a-Si/a-Si/a-SiGe三结叠层通讯卫星电池的制备技术.为了提高叠层电池的转换效率,提出改善n/i界面特性的缓冲层技术和高光敏性a-SiGe:H(F)薄膜的高氢气稀释比、低反应气压的淀积技术.通过工艺优化,研制出了AM1(100mW/cm~2)光照下转换效率为11.5%的a-Si/a-Si/a-SiGe三结叠层太阳电池.     

P型微晶硅在柔性太阳电池中的应用研究

以B(CH_3)_3为掺杂剂,采用正交实验法,以硅烷浓度、B(CH_3)_3掺杂比、反应压强及气体总流量等主要沉积参数为实验组变量,对P型微晶硅薄膜进行初步优化。在玻璃衬底上沉积厚度为80 nm左右的P型微晶硅(μc-Si:H)薄膜,通过测试材料暗态电导率、XRD、Raman等,研究了上述沉积参数对材料电学和微结构性能的影响,并在此基础上做进一步的参数优化,得到更高电导的微晶硅薄膜;将其应用于PEN衬底的非晶硅薄膜太阳电池中,得到6%的初始效率。     

薄膜电池争宠太阳能电池市场

太阳能电池产品主要分为晶体硅电池、薄膜电池2类:前者包括单晶硅电池、多晶硅电池2种,占据全球该行业绝大多数的市场份额;后者主要包括非晶硅电池、铜铟镓硒电池和碲化镉电池等,目前市场份额较小。     

薄膜太阳电池

硅太阳电池的应用日趋广泛,但昂贵的原材料成为其发展的瓶颈。薄膜太阳电池由于只需使用一层极薄的光电材料,材料使用非常少,并可使用软性衬底,应用弹性大,如果技术发展成熟,其市场面将相当宽阔。文章就迄今被人们广为关注的各类薄膜太阳电池,即非晶硅薄膜太阳电池、微(多)晶硅薄膜太阳电池、铜铟硒薄膜太阳电池、碲化镉薄膜太阳电池、染料敏化薄膜太阳电池和有机薄膜太阳电池的发展概况、技术难点和优缺点进行了论述。     

太阳能电池技术研究

介绍了第1代晶硅和第2代薄膜太阳能电池的发展状况,阐述了第3代GaAs叠层太阳能电池的基本原理、技术现状以及基于GaAs叠层电池的聚光光伏发电系统的技术优点和发展前景.     

非晶硅薄膜太阳电池的数值优化研究

基于Sentaurus TCAD数值分析平台,采用非晶硅的DOS模型对禁带中缺陷态进行表征,建立a-Si:H薄膜太阳电池的二维数值模型。对P-I-N结构的非晶硅太阳电池的本征区、P型区、N区以及P/I界面的特性进行研究,得到参数与薄膜太阳电池性能之间的关系。通过电池物理和结构参数的优化,在界面处引入ZnO作为反射层,优化得到太阳电池填充因子为74.7%,AM1.5下光电转换效率为10.1%,表明采用TCAD数值仿真可有效用于非晶硅太阳电池本征参数和反射层的优化设计,提高电池转换效率。     

a-Si(p)/c-Si(n)异质结太阳电池的AFORS-HET模拟优化

采用限定变量的方法,运用AFORS-HET(Automat FOR Simulation of HETerostructures)软件计算模拟了不同厚度、掺杂浓度和禁带宽度的非晶硅薄膜背场以及不同厚度、禁带宽度的非晶硅本征层对a-Si(p)/c-Si(n)异质结太阳电池的影响.结果表明,在其它参数不变的情况下,增加较薄的背场和中间本征层,可以提高太阳电池的整体性能,其光电转换有很大程度提高,其最高转换效率可达20.75％;其中,中间本征层在厚度不超过20 nm时,对电池的短路电流影响不大,而其它性能则相对下降;当非晶硅薄膜背场的掺杂浓度为1019 cm-3以上,带隙为1.7 eV,厚度为5 nm时,电池性能最佳.     

High efficiency a-Si//poly-Si tandem solar cell

A series of experimental trials has been carried out to realize the high efficiency a-Si//Poly-Si tandem solar cell. Employing p-type μc-SiC as a wide-gap heterojunction window, a-SiC as an interface buffer layer and n-type μc-Si as a back ohmic contact layer, 17.2 percent conversion efficiency has been achieved with the structure of ITO/p μc-SiC/n Poly-Si/n μc-Si heterojunction. Utilizing an optically transparent a-Si p-i-n cell as a top cell and inserting an optical coupler between the top and the Poly-Si bottom cell, a high total efficiency of 21.0 percent has been obtained so far on the four-terminal tandem cell. This conversion efficiency value represents a world record for a-Si basis tandem solar cells.     

光伏发电双轴自动跟踪控制系统的设计

太阳能光伏电池陈列的发电量与光线入射角角度有关,光线与光伏阵列平面垂直时发电量最大。采用太阳自动跟踪的方式,使太阳能电池板始终保持与太阳光垂直,可大大提高光伏阵列的发电量。采用光感跟踪与时间跟踪相结合的方法,设计了全天候太阳方位跟踪控制系统,系统功能包括检测、跟踪控制方式转换及双跟踪方式的控制。该双轴跟踪系统具有结构简单、稳定性好、精度高的特点,具有广阔的应用前景。     

Advanced electro-optical simulation of nanowire-based solar cells

The improvement of solar cell efficiency requires device optimization, including the careful design of contacts and doping profiles, and the development of light trapping strategies. In this context, electro-optical numerical simulation is essential to analyze the physical mechanisms that limit the cell efficiency and lead to design trade-offs. In this work we discuss the application of advanced electro-optical simulation to the analysis of nanowire-based solar cells. We demonstrate the possibility to combine two numerical tools to perform the electro-optical simulation in order to investigate critical issues and potentialities of nanowires for photovoltaic applications. Thanks to the adopted simulation methodology, requiring relatively low computational resources, analyses involving extended ranges of geometrical and physical parameters are performed. Nanowire-based (NW) solar cells are expected to outperform the thin-film counterparts in terms of optical absorptance. In this theoretical study we optimize the geometry of vertical crystalline–amorphous silicon core-shell NW arrays on doped ZnO:Al glass substrate by means of 3-D optical simulations in order to maximize the photon absorption. The optimized geometry is then analyzed by means of 3-D TCAD electrical simulation in order to calculate the ultimate efficiency and the main figures of merit. We show that optimized crystalline–amorphous silicon core-shell (c-Si/a-Si/AZO/Glass) NWs featuring height in the micrometer range can reach photogenerated current up to 22.94 mA/cm², approximately 40 % larger than that of the planar counterpart with the same amount of absorbing material, and maximum conversion efficiency close to 14 %.     

Electrode separation method to the boundary condition for a-Si TFT mixed-level simulation

This paper presents the electrode separation method for the boundary condition of a-Si TFT mixed-level simulation. The Poisson equation and the continuity equation are formulated into equivalent circuits. So, a circuit simulator can be used to handle the two-dimensional numerical simulation of a-Si TFT. The boundary condition problem between a semiconductor and an external circuit is solved by the electrode separation method. An electrode is separated into two nodes to fit Kirchhoff's current law and the semiconductor equations, respectively. A simple a-Si TFT/LCD circuit is taken as an example for the electrode separation method. For mixed-level simulation this technique is very useful. © 1998 John Wiley & Sons, Ltd.     

SIMULATION OF AMORPHOUS SILICON THIN-FILM TRANSISTOR INCLUDING ADAPTED GUMMEL METHOD

This paper presents an adapted Gummel method (AGM) used in the two-dimensional device simulation of an amorphous-silicon (a-Si) thin-film transistor (TFT). Firstly, the AGM for amorphous silicon is developed by modifying the Gummel method (GM) for crystalline silicon. Secondly, the AGM is implemented into a two-dimensional device simulator for the simulation of a-Si TFTs. The simulation results show that the AGM converges well while the GM fails to converge for the simulation of a-Si TFTs. Hence, the AGM is a useful technique for the simulation and analysis of a-Si TFTs. © 1997 by John Wiley & Sons, Ltd.     

Amorphous silicon-based guided-wave passive and active devices forsilicon integrated optoelectronics

Waveguides and interferometric light amplitude modulators for application at the 1.3- and 1.55-μm fiber communication wavelengths have been fabricated with thin-film hydrogenated amorphous silicon and its related alloys. The technique adopted for the thin-film growth is the plasma- enhanced chemical vapor deposition, which has been shown to give the lowest defect concentration in the film. Consequently the proposed waveguiding structures take advantage of the low optical absorption shown by a-Si:H at photon energies below the energy gap. In addition a good radiation confinement can be obtained thanks to the bandgap tailoring opportunity offered by this simple and inexpensive technology. In particular rib waveguides, based on a a-SiC:H/a-Si:H stack, have been realized on crystal silicon, showing low propagation losses. Recently, however, a new interest as low as 0.7 dB/cm. The same structure has been utilized for the fabrication of thermooptic Fabry-Perot modulators with switching times of 10 μs. Modulators based on the alternative waveguiding configuration ZnO/a-Si:H, giving comparable results, are also presented     

薄膜基板太阳能电池的高效率化技术

为实现薄膜基板太阳能电池的高效率化,富士电机最近开发了利用微晶硅（μc—si）的太阳能电池。做晶硅太阳能电池需要在高速下制膜（desposition）,尽管高速制膜与转换效率之间存在着折衷关系,但通过制膜方法与条件的改善,在4倍于初期的制膜速度下,达到了等于或高于初期开发阶段的高转换效率。如将这些技术应用于多结（multi-junction）太阳能电池中,则可达到比现有薄膜基板太阳能电池更高的稳定转换效率11．7％：