Factors leading to low cost dye sensitised solar cells with ‘go faster’ stripes

Abstract

Dye sensitised solar cells are a potential low cost photovoltaic technology because they can be manufactured by roll to roll processing. However, to achieve this, each manufacturing step must be extremely rapid (taking minutes at most). This paper addresses ultrafast dye sensitisation that can now be achieved in <5 min using one or multiple dyes. The use of multiple dyes can effectively give rise to any almost any desired colour in minutes, giving rise to ‘go faster’ stripes. This paper describes key parameters affecting dye uptake using metal containing (N719) and organic dyes (triphenylamine or squaraines) as examples.     

环境条件的改变对管簇结构腔体式吸收器热损的影响

分析了槽形抛物聚光集热器中管簇结构腔体式吸收器的热物理特性，依据其热阻网络、太阳能一般性控制方程对热损和所受边界条件的影响作了数值分析。     

Characterisation of solar cells and modules under actual operating conditions

A PC-based measuring system is presented for outdoor testing of solar cells and modules under real operating conditions. It consists of a sun-tracked sample holder, different electronic loads (including control), digital multimeters, a PC and a laser printer. Insolation is measured and recorded with pyranometers, pyrheliometers and a reference cell. Current-voltage curves are acquired in the range of irradiance from 10 W/m² to over 1000 W/m². Small single cells of size down to 3 mm by 3 mm as well as large modules and laminates up to 1 m by 1.5 m can be tested. The measurement time for one test can be varied between 5 to 15 seconds. The maximum power point (mpp) is normally detected on-line. However, it can also be determined in a subsequent mathematical analysis, if more precise mpp data are required. The maximum relative uncertainty in the efficiency (determined from mpp data) has been estimated to be less than ± 1 %, depending on type and size of cell or module and on the constancy of the insolation during the testing time. Using a new dynamic method, the temperature coefficient of the efficiency can be determined within a relative uncertainty of about ± 3 %. The coefficient is used to derive standard test condition data. Results are given for two commercial modules.     

Amorphous silicon solar cells

The perfectioning of the deposition techniques of amorphous silicon over large areas, in particular film homogeneity and the reproducibility of the electro-optical characteristics, has allowed a more accurate study of the most intriguing bane of this material: the degradation under sun-light illumination. Optical band-gap and film thickness engineering have enabled device efficiency to stabilize with only a 10–15% loss in the as-deposited device efficiency. More sophisticated computer simulations of the device have also strongly contributed to achieve the highest stable efficiencies in the case of multijunction devices. Novel use of nanocrystalline thin films offers new possibilities of high efficiency and stability. Short term goals of great economical impact can be achieved by the amorphous silicon/crystalline silicon heterojunction. A review is made of the most innovative achievements in amorphous silicon solar cell design and material engineering.     

薄膜太阳电池缺陷的电治疗技术

薄膜太阳电池性能与结构缺陷有关。对有某种缺陷陷的电池施加一定幅度的电压，同时观察其暗特性的变化，根据观察到的变化增减电压值，可消除缺陷，减少漏电，提高器件性能和制作成品率，这是一种简捷、有效、省时、省能的方法。本技术可作为薄膜太阳电池制造的常规工艺步骤而进入流水线，还可推广应用到其它固体薄膜器伯的研制、开发和生产上。     

平板型太阳能空气集热器有效透过率与吸收率乘积的计算

在分析平板型太阳能空气集热器内部传热原理的基础上，对其有效透过率与吸收率的乘积进行了讨论，导出了计算公式。     

青岛热泵辅助太阳能供热系统的性能分析

结合工程实例,对热泵辅助太阳能供热系统的流程进行了分析。对不同朝向、倾角平板集热器的表面太阳辐照度、太阳能热水系统热效率、空气源热泵制热性能系数进行了实测及计算。对于青岛地区,平板集热器宜采取朝南安装、倾角为45°。     

水库温度的预测研究

根据热传导理论近似建立了分层型水库水温变化的一维数学模型、由水库的实际资料模拟水温分布,并与水温实测值和规范统计法预测值进行了比较分析,得出了相对准确的水温分布结构.     

Estimation of global solar radiation using artificial neural networks

This paper introduces a neural network technique for the estimation of global solar radiation. There are 41 radiation data collection stations spread all over the kingdom of Saudi Arabia where the radiation data and sunshine duration information are being collected since 1971. The available data from 31 locations is used for training the neural networks and the data from the other 10 locations is used for testing. The testing data was not used in the modeling to give an indication of the performance of the system in unknown locations. Results indicate the viability of this approach for spatial modeling of solar radiation.     

Recent developments in high eficiency photovoltaic cells

Enormous progress has been made in recent years on a number of photovoltaic materials and devices in terms of conversion efficiencies. Efficiencies in the range of 18%–24% have been achieved in traditional silicon-based devices fabricated from both multicrystalline and single-crystal materials. Ultrahigh-efficiency (>30%) photovoltaic (PV) cells have been fabricated from gallium arsenide (GaAs) and its ternary alloys like gallium indium phosphide (GaInP₂). The high-efficiency GaAs-based solar cells are being produced on a commercial scale, particularly for space applications. Major advances in efficiency have also been made on various thin-film solar cells based on amorphous silicon (aSi:H), copper gallium indium diselenide (CIGS), and cadmium telluride materials. This paper gives a brief overview of the recent progress in PV cell efficiencies based on these materials and devices.