1MW高倍聚光光伏发电并网系统的设计

本文选云南石林地区为电站场址,通过对高倍聚光光伏组件选择、光伏阵列运行方式选择、光伏阵列设计及布置方案、并网逆变器选型等光伏发电系统构成方面进行了研究设计.分析得出该电站的理论年发电量为170.07万kWh,具有良好的经济效益和环保效益.     

屋顶型聚光光伏系统

介绍屋顶型聚光光伏系统的技术原理,对国内外相关企业的研究进展进行描述和归纳,从技术、政策、市场的可行性对该类产品进行分析和论述。     

上海地区晶硅光伏发电项目的可行性及发展前景

以100 kW的光伏发电系统为例,对上海地区晶硅太阳电池发电技术的可行性及发展前景进行了分析.分析结果表明,从动态投资回收期的角度来看,由于设备的投资成本较高导致发电成本较高,目前上海地区的晶硅光伏发电系统要完全商业化运行还不具备条件.分析结果还表明,晶硅组件及逆变器价格如果能够如果能够降到3.5元/W以下,按照目前的...     

固定式聚光光伏发电方案简介

利用太阳辐射能的光伏发电方式,具有许多非常独特的优点,比如发电过程一不耗水、二不耗气、三不耗煤、四不耗柴、五不耗油、六不耗铀;无噪声、无烟尘、无摩擦、无振动、无隐患、无需管理等。但同时也存在两个很明显的缺点——不稳定和成本高,除去在特殊场合(如航天器、孤岛等)的应用,还不存在和常规能源发电方式进行市场竞争的能力。如欲在电力市场占有一席之地,只有通过两种途径来实现——大步伐提高转换率或大幅度降低系统成本。本文介绍的"固定式聚光光伏发电"方案属于降低成本的一种尝试,近一年来     

低倍聚光光伏系统的实验研究

设计并建造了一台低倍聚光光伏发电系统,介绍了系统的结构,阐述了系统工作原理,并对其进行了实验研究,与固定安放的光伏系统进行了对比.根据实验结果,低倍聚光光伏系统在测量时段内的输出功率始终明显大于固定光伏系统,其总发电量是后者的3.18倍,这证明了这种光伏系统的优越性,所收集的电池温度、输出功率等数据对该类型聚光光伏系统的进一步研究有一定的参考价值.     

一种低倍聚光光伏系统的实验研究

提出一种拟抛物面聚光器,利用廉价的聚光器来代替电池组件,以此来降低成本。此聚光系统采用光电跟踪方法使聚光器始终正对着太阳。建立了实验系统,并通过实验分析此聚光光伏系统的性能。     

光伏发电自动跟踪系统

太阳电池方阵的发电量与阳光入射角有关,光线与太阳电池方阵平面垂直90°时发电量最大,改变入射角,发电量明显下降。目前,光伏发电系统普遍采用的是固定方阵发电方式。采用自动跟踪系统可提高发电量40%,从而降低投资20%。在哈尔滨工业大学和哈尔滨工程机械厂的协助下,哈尔滨阳光能源发展有限公司新近设计出光伏发电自动跟踪系统,并试制出演示模型(图1),2003年9月中旬在北京进行了户外测试,其自动跟踪效果令人满意。图1基本原理及结构:由两台电动机与减速机分别构成方位角转动机构和高度角转动机构,光电传感器内置放大,与太阳电池板方阵平面…     

漂浮式光伏发电系统的发电性能研究

漂浮式光伏发电技术是未来光伏发电的应用方向之一。在同一地点建立了1座6.3 kW漂浮式光伏发电系统及1座6.3 kW陆上光伏发电系统,分别对其发电性能进行数据采集与分析。试验表明,漂浮式光伏发电系统的总发电量比陆上光伏发电系统高2%,总体发电效率更高,漂浮式光伏发电系统降低温度损耗对系统发电功率的影响较明显。     

高聚光条件下砷化镓光伏电池特性的实验研究

设计并搭建了一种碟式聚光光伏发电系统,介绍了系统的结构,阐述了系统工作原理,并对其进行了户外实验研究。根据实验结果,该碟式聚光光伏系统的几何聚光倍数为150倍,其峰值功率为1.5315W/cm2,平均效率为26.58%,电池平均工作温度为46.875℃。太阳直接辐射强度和电池温度是影响三结砷化镓光伏电池性能的主要因素。与现有的单晶硅光伏电池片相比,三结砷化镓聚光光伏电池具有转换效率高、电学性能好等特点,所收集的电池温度、输出功率、效率等数据对碟式聚光光伏系统的进一步研究具有一定参考价值。     

光伏发电系统输出功率计算方法研究

准确计算光伏发电系统的输出功率,对光伏发电系统发电量的监管和光伏并网系统与电网调度、电力负荷等的配合问题具有重大意义。根据光伏发电系统的结构和工作原理,提出了光伏发电系统输出功率计算方法,可以计算任意太阳辐射量、环境温度、系统结构下的光伏发电系统输出功率。通过与真实光伏电站运行数据的比对,结果显示了光伏发电系统输出功率计算方法的适用性与准确性。     

Technical and economical system comparison of photovoltaic and concentrating solar thermal power systems depending on annual global irradiation

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.     

Comparative analysis of different grid-independent hybrid power generation systems for a residential load

Demand of electricity is rising all over the world, both in developing and developed countries due to escalation in world population and economic growth. The exploitation of renewable energy is imperative to mitigate energy crisis and to avoid the environmental downfall. The stochastic nature of many renewable energy sources sets techno-economic and functional limitations in their application for covering most types of energy needs. These limitations can be surmounted if a renewable and a conventional energy source are combined to formulate a hybrid generation power system.This paper examines the techno-economic feasibility of four hybrid power generation systems applied to cover the demand of a typical off-grid residence for a 20 years period. Each one of these hybrid power solutions should involve at least one renewable energy source technology and be able to cover all load needs. Four applications are investigated for each hybrid system, accounting to different geographical areas in Greece with diverse solar and aeolic profile. A comparative analysis is followed to set off the optimal solution based on a minimal total cost criterion.     

独立光伏发电系统充放电控制策略

为了提高蓄电池的充电效率和延长蓄电池的使用寿命,提出了一种新的光伏发电系统充放电控制策略.该控制策略用双蓄电池代替以前的单一蓄电池,在充电过程中,蓄电池按照光伏系统提供的电流进行充电,根据蓄电池的充电电压特性和内部的温度特性来判别充电终止电压.同时,采用电压、温度微分模糊控制算法,既能防止光照强度、温度等外部环境发生变化而导致对蓄电池充电的提前切除,又可保护蓄电池的过充.仿真结果证明,该控制策略能显著提高蓄电池的充电效率和延长蓄电池的使用寿命.     

Expanding photovoltaic penetration with residential distributed generation from hybrid solar photovoltaic and combined heat and power systems

The recent development of small scale combined heat and power (CHP) systems has provided the opportunity for in-house power backup of residential-scale photovoltaic (PV) arrays. This paper investigates the potential of deploying a distributed network of PV + CHP hybrid systems in order to increase the PV penetration level in the U.S. The temporal distribution of solar flux, electrical and heating requirements for representative U.S. single family residences were analyzed and the results clearly show that hybridizing CHP with PV can enable additional PV deployment above what is possible with a conventional centralized electric generation system. The technical evolution of such PV + CHP hybrid systems was developed from the present (near market) technology through four generations, which enable high utilization rates of both PV-generated electricity and CHP-generated heat. A method to determine the maximum percent of PV-generated electricity on the grid without energy storage was derived and applied to an example area. The results show that a PV + CHP hybrid system not only has the potential to radically reduce energy waste in the status quo electrical and heating systems, but it also enables the share of solar PV to be expanded by about a factor of five.     

Impact of subsidy policies on diffusion of photovoltaic power generation

This paper constructs panel data from an 11-year data set on all 47 prefectures of Japan, covering the period 1996–2006 . We use this data set to analyze the factors affecting photovoltaic (PV) system diffusion. Our empirical results show that the regional government policy clearly helps to promote PV system adoption. It is also found that installation costs have a significant negative effect on PV system adoption, whereas housing investment and environmental awareness among residents have a positive effect. We believe that this finding has a significant implication for further PV system diffusion because it suggests the importance of regional diffusion policies reflecting the environmental awareness of regional residents.     

SmartGrid: Future networks for New Zealand power systems incorporating distributed generation

The concept of intelligent electricity grids, which primarily involves the integration of new information and communication technologies with power transmission lines and distribution cables, is being actively explored in the European Union and the United States. Both developments share common technological developmental goals but also differ distinctly towards the role of distributed generation for their future electrical energy security. This paper looks at options that could find relevance to New Zealand (NZ), in the context of its aspiration of achieving 90% renewable energy electricity generation portfolio by 2025. It also identifies developments in technical standardization and industry investments that facilitate a pathway towards an intelligent or smart grid development for NZ. Some areas where policy can support research in NZ being a “fast adapter” to future grid development are also listed.This paper will help policy makers quickly review developments surrounding SmartGrid and also identify its potential to support NZ Energy Strategy in the electricity infrastructure. This paper will also help researchers and power system stakeholders for identifying international standardization, projects and potential partners in the area of future grid technologies.     

Strategic selection of suitable projects for hybrid solar-wind power generation systems

Because of the pressing need for maintaining a healthy environment with reasonable costs, China is moving toward the trend for generating electricity from renewable resources. Both solar energy and wind power have received a tremendous attention from private associations, political groups, and electric power companies to generate power on a large scale. A drawback is their unpredictable nature and dependence on weather. Fortunately, the problems can be partially tackled by using the strengths of one source to overcome the weakness of the other. Especially, a large fraction of the solar resource is available at times of peak electrical load. However, the complexity of using two different resources together makes the hybrid solar-wind generation systems more difficult to analyze. Accordingly, this paper first briefly introduces the solar-wind generation system and next develops its critical success criteria. Then, a fuzzy analytic hierarchy process associated with benefits, opportunities, costs and risks, is proposed to help select a suitable solar-wind power generation project.     

某15MW太阳能屋顶光伏发电工程的应用分析

在对太阳能屋顶光伏发电系统构成及发展意义阐述的基础上,通过对某15MW屋顶光伏发电工程大量实际数据的分析,表明太阳能屋顶光伏发电工程具有良好的社会、经济效益和广阔的发展前景。     

Interface effects on the carrier transport and photovoltaic properties of hydrogenated amorphous silicon/crystalline silicon solar cells

Current-voltage-temperature (I-V-T) characteristics evaluated near 150K and 300K were used to study the photovoltaic property variations in hydrogenated amorphous silicon (a-Si:H)/crystalline silicon (c-Si) solar cells. The possible carrier transport mechanisms in such devices were examined from the I-V-T data which indicated a significant influence of the amorphous /crystalline interface on the short-circuit current density (J_sc) and open-circuit voltage (V_oc) of the solar cells. Carrier transport near 300K for forward biases was by a multi-tunneling mechanism and became space charge limited with increasing bias. For devices having low J_sc and V_oc an additional region was seen in both forward and reverse biases, at low temperatures, where the current simply varied linearly with the applied bias. This characteristic manifested in both high and low temperatures region for devices with still lower photovoltaic properties, which has been reasoned to be due to a higher interface density. Passivating the c-Si surface with HF just prior to the amorphous layer deposition resulted in a large improvement in the properties. The most significant effect was on the J_sc which improved by an order of magnitude. The treatment also affected the lower temperature I-V-T data in that the current fell to very low levels. The spectral response of the treated solar cells showed enhanced blue/violet response compared with the unpassivated devices. The interface passivation plus reducing a-Si thickness has improved the solar cell efficiency from 0.39% to 9.5%.     

Assessment of massive integration of photovoltaic system considering rechargeable battery in Japan with high time-resolution optimal power generation mix model

Maximizing renewables in the country's power system has been a key political agenda in Japan after the Fukushima nuclear disaster. This paper investigates the potential of PV resource, which could be systematically integrated into the Japanese power system, using a high time-resolution optimal power generation mix model. The model allows us to explicitly consider actual PV and wind output variability in 10-min time resolution for 365 days. Simulation results show that, as PV expands, the growth of PV integration into the grid slows down when the installed PV capacity is more than the scale of the peak demand, although Japan has immense potential of installable PV capacity – equivalent to 40 times of the peak. Secondly, the results imply that a large-scale PV integration potentially decreases the usage ratio of LNG combined cycle (LNGCC) in specific seasons, which is a challenge for utility companies to ensure that LNGCC is used as a profitable compensating generator for PV variability. Finally, a sensitivity analysis on rechargeable battery cost suggests that the reason for suppressing the PV output instead of storing its surplus output by the battery can be attributed to the high battery cost; hence, the improvement of its economic performance is significant to integrate the massive PV energy.