Array, photovoltaic cells

A photovoltaic material generates a voltage when it is exposed to light and photovoltaic can be considered as a specialized area of optoelectronics. The principle has been known for many decades but it became a industrial reality only in 1958 when an array of photovoltaic cells, based on single-crystal silicon, provided power for a space vehicle. 

Another solar firm, SolFocus (www.solfocus.coml has developed solar arrays that use just one-thousandth as much semiconductor material as standard solar panels. The arrays are set with curved mirrors that focus sunlight onto solar cells measuring one-square centimeter, which concentrates the light 500 times. These cells efficiency is greater than 38%, compared to the 13% to 19% efficiency for silicon photovoltaic cells. SolFocus projects that costs per kilowatt-hour will fall from 24 to 28 cents in 2008 to 13 to 14 cents by 2010. 

Array of solar panels (photovoltaic cells) on the roof of terraced houses in Heerhugowaard in the Netherlands. This is part of a Dutch government pilot project to investigate clean, renewable energy forms such as solar power. The 10 houses in this terrace (only two seen here) have a total of 200 square meters of solar panels on their roofs. The total power output of these solar panels is 24.6 kilowatts. The photovoltaic cells contain a semiconducting material that converts sunlight directly into electricity. Solar power is relatively cheap, as once the panels are installed, they continue to produce electricity indefinitely. (Courtesy of Martin Bond/Science Photo Library)... 

There are a number of different types of photon detectors, including the photomultiplier tube, the silicon photodiode, the photovoltaic cell, and a class of multichannel detectors called charge transfer devices. Charge transfer detectors include photodiode arrays, charge-coupled devices (CCDs), and charge-injection devices (ClDs). These detectors are used in the UV/VIS and IR regions for both atomic and molecular spectroscopy. 

A photovoltaic cell is a device that converts the sun s energy into electricity. We can group photovoltaic cells together in an array (see Figure 9-6). The cells are grouped together because... 

We can combine one or more arrays with batteries to store the electricity generated by the photovoltaic cells. We use photovoltaic to power emergency phones along highways, satellites, the international space station, private houses, and even solar cars. 

AI2O3/multilayer array of chlorophyll a/Ag photovoltaic cell characteristics by treatment of the aluminium electrode, J. Phys. Chem. 88 950 (1984). 

Conjugated polymers, in the undoped state, exhibit the electronic and optical properties of semiconductors in combination with the mechanical properties of general polymers, making them potentially useful for a wide array of applications particularly in organic optoelectronic devices such as polymer LEDs, photodetectors, photovoltaic cells, etc. Development in the performance of such devices has advanced rapidly, and prototype devices now meet realistic specifications for practical applications. In spite of such successful achievements in the scope of device application, however, there is still controversy over the nature of the electronic structure and the appropriate description of the underlying physics of elementary excitations. Since these issues are both scientifically interesting and critically important to the assessment of the future potential of devices based on conjugated polymers, more detailed... 

Mor GK, Shankar K, Paulose M, Vaighese OK, Grimes CA (2007) High efficiency double heterojunction polymer photovoltaic cells using highly ordered Tr02 nanotube arrays. Appl Phys Lett 91 152111. doi 10.1063/1.2799257... 

Polymer-templated fullerene nano-arrays can be produced using ionic interactions between charged polymers and fuUerene derivatives [93]. Schanze, Reynolds and coworkers have reported that the layer-by-layer self-assembly approach can be used to fabricate an active material layer made up of PPE-SOj 15, PPE-EDOT-SOJ 16 and [60]fullerene 17 for photovoltaic cells (EDOT = 3,4-ethylenedioxythiophene) (Figure 9.20) [94]. Multiple, layer-by-layer deposition of the polymers and com-... 

Semiconductor NCs have been incorporated into solar cells in different configurations, for example (a) photoelectrodes composed of quantum dot arrays, (b) metal-semiconductor photovoltaic cells,(c) NC-polymer solar cells and (d) quantum dot sensitized solar cells. This field has been the focus of intense research in recent years because of the possibility that quantum dot-based solar cells can overcome the Shockley-Queisser photoconversion limit. This possibility relies on two feasible processes hot carrier extraction and multiple exciton generation (MEG). 

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]. 

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