Realistic generation cost of solar photovoltaic electricity

Solar photovoltaic (SPV) power plants have long working life with zero fuel cost and negligible maintenance cost but requires huge initial investment. The generation cost of the solar electricity is mainly the cost of financing the initial investment. Therefore, the generation cost of solar electricity in different years depends on the method of returning the loan. Currently levelized cost based on equated payment loan is being used. The static levelized generation cost of solar electricity is compared with the current value of variable generation cost of grid electricity. This improper cost comparison is inhibiting the growth of SPV electricity by creating wrong perception that solar electricity is very expensive. In this paper a new method of loan repayment has been developed resulting in generation cost of SPV electricity that increases with time like that of grid electricity. A generalized capital recovery factor has been developed for graduated payment loan in which capital and interest payment in each installment are calculated by treating each loan installment as an independent loan for the relevant years. Generalized results have been calculated which can be used to determine the cost of SPV electricity for a given system at different places. Results show that for SPV system with specific initial investment of 5.00 $/kWh/year, loan period of 30 years and loan interest rate of 4% the levelized generation cost of SPV electricity with equated payment loan turns out to be 28.92 ¢/kWh, while the corresponding generation cost with graduated payment loan with escalation in annual installment of 8% varies from 9.51 ¢/kWh in base year to 88.63 ¢/kWh in 30th year. So, in this case, the realistic current generation cost of SPV electricity is 9.51 ¢/kWh and not 28.92 ¢/kWh. Further, with graduated payment loan, extension in loan period results in sharp decline in cost of SPV electricity in base year. Hence, a policy change is required regarding the loan repayment method. It is proposed that to arrive at realistic cost of SPV electricity long-term graduated payment loans may be given for installing SPV power plants such that the escalation in annual loan installments be equal to the estimated inflation in the price of grid electricity with loan period close to working life of SPV system.     

Reliability analysis of solar photovoltaic system using hourly mean solar radiation data

This paper presents the hourly mean solar radiation and standard deviation as inputs to simulate the solar radiation over a year. Monte Carlo simulation (MCS) technique is applied and MATLAB program is developed for reliability analysis of small isolated power system using solar photovoltaic (SPV). This paper is distributed in two parts. Firstly various solar radiation prediction methods along with hourly mean solar radiation (HMSR) method are compared. The comparison is carried on the basis of predicted electrical power generation with actual power generated by SPV system. Estimation of solar photovoltaic power using HMSR method is close to the actual power generated by SPV system. The deviation in monsoon months is due to the cloud cover. In later part of the paper various reliability indices are obtained by HMSR method using MCS technique. Load model used is IEEE-RTS. Reliability indices, additional load hours (ALH) and additional power (AP) reduces exponentially with increase in load indicates that a SPV source will offset maximum fuel when all of its generated energy is utilized. Fuel saving calculation is also investigated. Case studies are presented for Sagardeep Island in West Bengal state of India.     

Electricity generation cost between proposed photovoltaic station and conventional units in Kuwait

A full analysis is shown in this paper for the cost of kWh generated from a photovoltaic station located in Kuwait. By using 21 years of weather data for Kuwait, the yearly generated energy was found by proposing the PV station capacity with known panel tilt angle. The cost of kWh generated from the PV station was compared with the kWh generated from conventional units in the country. A sensitivity analysis was done to some factors: capital cost per installed PV peak watt, discount rate, and operating peak hours, which affect the cost of kWh production from both PV and conventional units. If the PV station is proposed to be installed in Kuwait, the capital cost per PV installed peak watt must be less than today's prices.     

Cost and sensitivity analysis for photovoltaic station in Kuwait

A full analysis is shown in this paper for the cost of kWh generated from photovoltaic station located in Kuwait. By using a 21 years weather data for Kuwait, the yearly generated energy was found by proposing the PV station capacity with known panels tilt angle. The cost of kWh generated from PV station was compared with the kWh generated from conventional units in the country. A sensitivity analysis was done to some factors; capital cost per installed PV peak watt, discount rate, and operating peak hours, which affect the cost of kWh production from both PV and conventional units. If the PV station is proposed to be installed in Kuwait, the capital cost per PV installed peak watt must be less than today's prices.     

Parametric cost analysis of photovoltaic systems

A parametric cost analysis of photovoltaic systems based on different design philosophies has been carried out. The analysis takes into account the fixed costs involved in a photovoltaic installation (such as site preparation, array foundations and structure, inversion equipment, backup capacity, etc.) the cost of concentrators at different concentration ratios ranging from unity (i.e. flat plate array) to 10³, solar cell cost-per-unit area, system efficiency, etc. Resulting parametric curves allow the determination of the cost of electricity for a given set of system constraints. They also allow one to determine the optimum concentration ratio for a given solar cell cost per unit area. The analysis confirms many of the accepted conclusions, presents them in a concise form, and, in addition, allows one to see the relationship between the various system design regimes and the sensitivity of the total cost of electricity produced to the cost of the various system components.     

利用计算机模拟太阳能光伏发电

太阳能光伏发电是利用太阳能电池这种半导体电子器件有效地吸收太阳光辐射能,并使之转换成电能的直接发电方式。开发利用太阳能这种可再生的清洁能源发电是解决能源短缺、保护环境的重要途径。本文概述了太阳能光伏发电技术的研究情况,根据传热学及相关知识建立数学模型,并运用Lab VIEW软件对该系统进行动态模拟与仿真。     

Thermodynamic analysis of solar photovoltaic cell systems

The thermodynamic characteristics of solar photovoltaic (PV) cells are investigated from a perspective based on exergy. A new efficiency is developed that is useful in studying PV performance and possible improvements. Exergy analysis is applied to a PV system and its components, and exergy flows, losses and efficiencies are evaluated. Energy efficiency is seen to vary between 7% and 12% during the day. In contrast, exergy efficiencies, which incorporate the second law of thermodynamics and account for solar irradiation exergy values, are lower for electricity generation using the considered PV system, ranging from 2% to 8%. Values of “fill factors” are determined for the system and observed to be similar to values of exergy efficiency.     

Network analysis of fault-tolerant solar photovoltaic arrays

Large solar photovoltaic array networks have been investigated to find a configuration that is comparatively less susceptible to electrical mismatches due to manufacturer's tolerances in solar cell characteristics and shadow problems. Three network configurations have been selected for comparison: series-parallel, total-crossed-tied and bridge-linked. Explicit mathematical analysis based on randomly generated parameters of solar cell characteristics is presented. Series resistance of the constituent cells has been taken into account. The computational schemes for the array configurations of arbitrary size have been developed and implemented in numerical algorithms and computer programs. The illustrative numerical computations have shown that the bridge-linked array interconnection network under most conditions is superior to and never worse than the total-cross-tied and significantly superior to the series-parallel network in its fault-tolerance due to shadow effects and manufacturer's tolerances in cell characteristics.     

一种聚光型太阳能光伏系统的研究

讨论了多平面镜作直线布置的聚光器设计原理,给出了单镜面的面积计算方法和平面镜二维旋转角度的计算方法,并分析了在太阳能电池接收最佳光强Em可获得最佳发电量控制策略要求。实验采用9平面镜构成抛物面聚光器,太阳能电池接收光源达到额定光强的5倍左右,在太阳能电池标准配置下很大地提高了光伏系统的输出功率。     

太阳能光伏冰箱技术的应用分析

文章结合太阳能制冷技术的特点,指出了太阳能光伏冰箱研发的重要性,并对太阳能光伏冰箱系统的基本组成及工作原理进行了介绍;进而,分别从光伏转换效率和优化设计两个方面,对太阳能光伏冰箱系统的实际应用中存在的关键问题进行了分析。最后,结合太阳能光伏冰箱技术的研究现状和当前太阳能电池的生产成本变化,指出了太阳能光伏冰箱技术应用的市场前景广阔。     

Effective solar radiation based benefit and cost analyses for solar water heater development in Taiwan

To reduce greenhouse gases emissions, promoting solar water heaters (SWHs) has become an essential national policy in Taiwan. To implement this policy effectively, the applicability of SWHs in different regions must be analyzed. Previous studies generally performed SWH benefit-cost analyses based on total annual solar radiation; however, this method may overestimate energy production benefits because, for an SWH, the solar energy captured today cannot be preserved. Therefore, this study proposes the concept of effective solar radiation (ESR), which is based on potential heat output estimated using tap water temperature and solar radiation in each region. The benefits of SWHs are then assessed based on the number of effective days and ESR, instead of using total annual solar radiation. A procedure is established to evaluate the applicability of SWHs in each region based on proposed benefit-cost analyses. Possible outcomes of a national SWH program are estimated. The sensitivities of essential factors, including collector efficiency, installation cost, and discount rate, are also analyzed. Analytical results show that the ratios of ESR to total annual solar radiation for regions in Taiwan are about 82-89%. The payback periods vary at 6-15 years for different regions and heater types being replaced. The national program is expected to reduce greenhouse gases emissions by approximately 150,000 tons eCO₂ annually.     

The Indian solar photovoltaic industry: a life cycle analysis

This paper applies the product life cycle framework to analyze the impact of global trends on the Indian photovoltaic industry. The author believes that consolidation in the Indian industry simultaneous with exploiting its comparative advantage of flexible and low cost production techniques would help it stand on its own feet beyond the protectionist subsidy era. Service provision and financing are likely to represent significant revenue opportunities while dwindling margins on module manufacture would expedite formation of vertically integrated energy service delivery chains.     

Light-splitting photovoltaic system utilizing two dual-junction solar cells

There are many difficulties limiting the further development of monolithic multi-junction solar cells, such as the growth of lattice-mismatched material and the current matching constraint. As an alternative approach, the light-splitting photovoltaic system is investigated intensively in different aspects, including the energy loss mechanism and the choice of energy bandgaps of solar cells. Based on the investigation, a two-dual junction system has been implemented employing lattice-matched GaInP/GaAs and InGaAsP/InGaAs cells grown epitaxially on GaAs and InP substrates, respectively.     

Economic analysis of photovoltaic-powered solar domestic hot water systems in Kuwait

The present paper first presents a comparison between the photovoltaic four-parameter and five-parameter models. The comparison was performed using polycrystalline and amorphous silicon solar cells. The results showed that the four-parameter model can accurately determine the I–V characteristics of single- and polycrystalline solar cells. On the other hand, the five-parameter model can be used to accurately determine the I–V characteristics of amorphous solar cells in addition to its capability of predicting the I–V characteristics of single- and polycrystalline solar cells.Secondly, the economic feasibility of photovoltaic-powered solar water heating systems in Kuwait has been examined. The system includes photovoltaic arrays instead of solar collectors used in common solar water heating systems. The five-parameter model was used to simulate the performance of amorphous silicon modules used with the photovoltaic-powered solar water heating systems. Oil prices in the range of US$20–30 per barrel were studied. At the current prices of photovoltaic modules and a low oil price, photovoltaic-powered solar water heating systems were found to be economical. On the other hand, assuming a low oil price, the price of photovoltaic modules should be reduced to 50% of their current prices to make photovoltaic-powered solar water heating systems feasible in the Kuwaiti climate.     

Experimental study and analysis on novel thermo-electric cooler driven by solar photovoltaic system

Experimental study and analysis on thermoelectric cooler driven by solar photovoltaic system has been carried out. Here the research attention is on testing of system performance under solar insolation. Experimental results revealed that unit could maintain the temperature in the cooler at 10–15°C and have a coefficient of performance (COP) of about 0.34. Analysis of thermoelectric cooling system has been conducted on the basis of COP, cooling capacity and environmental issues. Further investigations verified that the performance of the system is a function of solar insolation rate and temperature difference of hot and cold sides of thermoelectric module etc. There subsist most favorable solar insolation rate which allows COP and cooling production to be maximum value respectively. It is anticipated that the cooler would have prospective for cold storage of vaccine, food and drink in remote and rural areas or outdoor conditions where electricity is not available.     

Experimental study of photovoltaic solar assisted heat pump system

A novel photovoltaic solar assisted heat pump (PV-SAHP) system has been proposed in this study. Performance tests with a range of condenser supply water temperature were conducted on an experimental rig. The dynamic performance of this PV-SAHP system in a 4-day period with very similar weather conditions was analyzed and the influencing factors were identified. The results indicate that this PV-SAHP system has a superior coefficient of performance (COP) than the conventional heat pump system and at the same time, the photovoltaic efficiency is also higher. The COP of the heat pump was able to reach 10.4 and the average value was about 5.4. The average photovoltaic efficiency was around 13.4%. The highest overall coefficient of performance (COP_p/t), bringing into consideration both the photovoltaic and thermal efficiency, was about 16.1.     

风光互补发电系统中光伏方阵最佳倾角的计算方法

介绍一种计算风光互补发电系统中光伏方阵的最佳倾角的方法。用最小二乘法确定光伏方阵的最佳倾角:先计算出倾角β下各月倾斜面上的太阳能方阵发电量与风机发电量之和,然后减去各月负载耗电量的差,再求出一年内上述差值的平方和,能使得此平方和取得最小值的倾角即为方阵最佳倾角β。根据此方法确定出的最佳倾角可以使太阳能和风机发电量相对不足的月份的发电量尽量接近负载需求量,同时又可以解决有的月份风光发电量远大于负载需求,造成极大浪费的问题。     

内蒙古偏远牧区户用光伏发电系统的经济性与环境效益分析

离网光伏发电系统的经济性,主要体现在系统成本与投资收益的对比关系上。通过在内蒙古某偏远牧区安装小型家用离网光伏发电系统进行监测及数据采集,从投资成本、系统收益及环保贡献方面对离网光伏发电系统经济性的影响进行分析。结果表明:离网光伏发电系统的投资收益并不明显,但针对偏远地区用电不便的问题,却有很大帮助及改善,并且在节能减排方面也有很大贡献。而且从长远看,系统成本的降低对其经济性的提高有很大的影响。所以希望通过政策补贴等的方式,提高离网系统在发展初期的投资收益,并为在内蒙古地区推广离网光伏发电系统提供积极的示范作用。     

Energy and cost analysis of semi-transparent photovoltaic in office buildings

Solar energy conversion systems and daylighting schemes are important building energy strategies to produce clean energy, reduce the peak electrical and cooling demands and save the building electricity expenditures. A semi-transparent photovoltaic (PV) is a building component generating electricity via PV modules and allowing daylight entering into the interior spaces to facilitate daylighting designs. This paper studies the thermal and visual properties, energy performance and financial issue of such solar facades. Data measurements including solar irradiance, daylight illuminance and output power for a semi-transparent PV panel were undertaken. Using the recorded results, essential parameters pertaining to the power generation, thermal and optical characteristics of the PV system were determined. Case studies based on a generic reference office building were conducted to elaborate the energy and cooling requirements, and the cost implications when the PV facades together with the daylight-linked lighting controls were being used. The findings showed that such an integrated system could produce electricity and cut down electric lighting and cooling energy requirements to benefit the environmental, energy and economic aspects.     

基于太阳能光伏热利用的光伏/热电(PV/TV)建筑一体化试验研究

将太阳能电池板、集热器、热电发电片结合起来,设计并制成了一套光伏/热电(PV/TV)系统,在利用太阳能电池发电的同时,收集热量并利用其发电。在北京地区进行了该系统的室外模拟试验,测试并讨论了该系统在不同结构和不同环境下的性能,探讨该系统在光伏建筑中的应用。试验结果表明,与单纯的光伏发电系统或太阳能热水系统相比,PV/TV系统具有占地面积小、综合效率高等优点。