Photovoltaics arrays

Pig. 1. An integrated high concentration photovoltaic array that achieved a solar conversion efficiency exceeding 20% in a 2000-W testbed (7). 

Unlike solar thermal systems or PV concentrator systems, the PV flat plate systems work well in cloudy locations because these latter convert diffuse as well as direct sunlight to electricity. On an aimualized basis, the energy produced by a photovoltaic array varies by only about 25% from an average value for the contiguous 48 states of the United States. As a result, it is practical to use photovoltaic systems in normally cloudy locations such as Seattle or northern Maine. 

Solar Power With improved technology and production methods considerable use is being made of solar power in remote locations. The output of photovoltaic arrays is used to maintain conventional storage batteries in a state of charge. The cathodic protection system is in turn energised from the batteries. It is usual to incorporate sufficient battery storage to accommodate a number of no-sun days. Whilst in theory the capacity of equipment is unlimited, a practical maximum would be ca. SOO W. 

Thomas, R. E. Gaines, B. G. "Methodology for Designing Accelerated Aging Tests for Predicting Life of Photovoltaic Arrays" Department of Energy/National Bureau of Standards Workshop on Stability of Thin Film Solar Cells and Materials, Washington, D.C., May 1-3, 1978. 

The Hydrogen Research Institute in Canada has developed and tested a stand-alone renewable energy system composed of a 10 kW wind turbine, a 1 kWpeak photovoltaic array, a 5 kW alkaline electrolyzer, and a 5 kW PEM fuel cell. The components of the system are electrically integrated on a 48 V DC bus [50]. 

Photovoltaic Array. For Case 1, a total of 588 individual modules are used in the simulation, and the array is configured with 147 parallel strings of 4 modules each. The panels are tilted at an angle of 45° to optimize electricity production during the winter months. Using the manufacturer s guaranteed power output of 100 W per module at standard test conditions (irradiance = 1000 W/m2, cell temperature = 25°C), the peak power output of the array is expected to be 58.8 kW. 

More specifically for photovoltaics a capital cost of 6,750 /kW was used in this analysis, resulting in a total capital cost 59,400 for a PV array with a total installed capacity of 8.8 kW. In addition the O M for photovoltaic arrays is considered practically zero. 

Moreover, the cost of diesel fuel was considered equal to 0.8 /L and the project lifetime was 16 years. The results of the existing PV-diesel power system simulation showed that 17% of system s electricity production comes from the photovoltaic array and the remaining 83% is produced by the diesel generator. 

The distribution of total annualised costs for the envisaged PV-hydrogen system of Rambla del Agua (using current costs of hydrogen technologies) is presented in Table 5.18. As can be seen from this table, a major cost factor for the proposed system is the photovoltaic array (approximately 59% of total annualised costs), followed by the fuel cell (only 13 % of total annualised costs). 

Tracking scheme of photovoltaic array single north-south axis... 

The assumed conditions used in evaluating characteristics of the systems are summarized in Table 2. The total areas of the solar collectors and photovoltaic arrays are assumed to be 10 ha. In the solar thermal and hybrid systems, the type of collector is parabolic trough, the condenser outlet pressure 0.1 kg/cm a, and the capacity (maximum net power output) has been determined so as to minimize the unit cost of generated power energy. In the solar photovaltaic system, the conversion efficiency at the array is assumed to be 15 %. The tracking scheme of the solar collector and photovoltaic array is single north-south axis. 

Fig. 14.7. Photovoltaic array located at Padre Cocha in Peru.

Continue to develop additional modules in the Simulink library, including a photovoltaic array, an electrolyzer, a battery, a wind turbine, and an autothermal reformer. 

Carmichael, D. C. "Studies of Encapsulation Materials for Terrestrial Photovoltaic Arrays" 5th Quarterly Progress Report" ERDA/JPL-954328-76/6 Battelle Columbus Laboratories Columbus, OH, 1976. 

Encapsulants are necessary for electrical Isolation of the photovoltaic circuit. They also provide mechanical protection for the solar cell wafers and corrosion protection for the metal contacts and circuit interconnect system over the 20-year design life of a photovoltaic array. The required components Include the solar cell circuit, the rigid or structural member, the pottant, and the outer cover/insulator. Surface modifications may be needed to develop strong, stable bonds at the Interfaces in the composite. If the module is to be framed, edge sealants may also be required. The functions of the Individual components and the performance requirements as they are now known are described. Costs are ccmipared where possible and candidate materials identified. 

Hybrid Renewable Energy System - A renewable energy system that Includes two different types of renewable energy technologies that produce the same type of energy for e.g., a wind turbine and a solar photovoltaic array combined to meet a power demand. 

Kapton s high specific strength and good thermal stability make it good space structural material. Space station designs envision large Kapton blankets as supports for photovoltaic arrays. Erosion of the Kapton would cause texturing of the surface... 

The output forecast for photovoltaic integrated in foil and membrane constructions is significantly more complex than for standard photovoltaic arrays, for the following reasons ... 

Sadok, M., Mehdaoui, A. Outdoor testing of photovoltaic arrays in the Saharan region. Renew. Energy 33(12), 2516-2524 (2008)... 

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