Thinner crystalline silicon cells are under development, but must be provided with the discussed optical properties, resulting in increased. Solar cell technology university of massachusetts boston. Types of solar cells experiment 3 generations generation 1. A photovoltaic device produces a current or a voltage at its output in the presence of light. These notes introduce important solar energy facts and contain links to sites that best explain various solar concepts. Solar cells are described as being photovoltaic, irrespective of whether the source is sunlight or an artificial light. The use of solar power for home, office, barn, etc.
In this paper, a distributed spicemodel for a solar cell is worked out. Gray purdue university, west lafayette, indiana, usa 3. Many of the topics that are discussed in this book are also covered in the massive open online course mooc on solar energy delftx, et. Sunlight enters the cell through the transparent sno 2. Voltage is generated by solar cells made from specially treated semiconductor materials, such as silicon. Lecture 3 types of solar cells experiment 3 generations. Cheaper than silicon, especially in thinfilm solar cell technology not as efficient band gap 1. For instance, in the fabrication of a photovoltaic solar cell, silicon, which. The amorphous word with respect to solar cell means that the comprising silicon material of the cell lacks a definite arrangement of atoms in the lattice, noncrystalline structure, or. Solar cells are used on spaceships like the international space station pictured below, but are also used on earth in places that get lots of sunlight throughout the year.
Cbse ncert notes class 12 physics semiconductor electronics. Sep 21, 2014 electronic materials, devices, and fabrication by prof s. Fundamental properties of solar cells, principles and. When photons of light fall on the cell, they transfer. The solar cell traps all the electrons released by the silicon and pushes them in one direction, which creates an electric current. The physics of solar cells by jenny nelson, imperial college press, 2003. The following sections address some materials aspects of iiiv solar cell development with a focus on design for maximum efficiency resting on the flexibility afforded by this family of materials.
A solar cell is basically a semiconductor pn junction device. The solar cell is the basic building block of solar photovoltaics. Let us note some qualities of the barrier figure 26d. Three generations of solar cells, crystalline silicon solar cells, thin lm solar cells and photoelectrochemical cells, are described by means of their.
Questions on the solar system funnily turn up in both geography and science. Solar spectrum on earth is black body radiation modified by molecular absorption in the atmosphere. It is a form of photoelectric cell, defined as a device whose electrical characteristics, such as current, voltage, or resistance, vary when exposed to light individual solar cell devices can be. Electronic materials, devices, and fabrication by prof s.
It consist of silicon, germanium pn junction with a glass windows on the top surface layer of ptype, the ptype material is made very thin and wide so that the. The common single junction silicon solar cell can produce a maximum opencircuit voltage of approximately 0. We give the upper limit to the solar cell e ciency. Individual solar cell devices can be combined to form modules, otherwise known as solar panels. An overview of solar cell technology mike mcgehee materials science and engineering global climate and energy projectglobal climate and energy project center for advanced molecular photovoltaics precourt institute stanford university konarka nanosolar john benner provided the slides with the nrel logo. Single and polycrystalline silicon growth, impurity diffusion, contacts. Lecture 8 the solar cell lecture mit opencourseware. Application of pn junctions within solar cells is discussed. Dye sensitized solar cell dssc lecture for eng 230. When solar light falls on a pn junction, it generates emf.
Silicon is the most commonly used semiconducting material in solar energy. Solar cell types there are several types of solar cells being developed. Usually sandwiched with cadmium sulfide cds to form a pn junction photovoltaic solar cell. Many different solar cell technologies are being developed, for various applications rooftops, solar power plants, satellites, backpacks or clothing, etc. This chapter only discusses the use of solar energy for the direct production of electricity photovoltaic solar energy.
This seminar is a short overview of current photovoltaics. Introduction solar cells based on cuin,gase 2 cigs. Options for harnessing solar energy thermal, catalysis, combined technologies, photovoltaic, and their respective current and projected costspotential, compared to traditional sources. The triiodide then recovers its missing electron by mechanically diffusing to the bottom of the cell, where the counter electrode reintroduces the electrons after flowing through the external circuit. Study of iv characteristic of a solar cell illuminated by an incandescent lamp, at. The national renewable energy laboratory nrel maintains a plot of compiled values of highest confirmed conversion efficiencies for research cells, from 1976 to the present, for a range of photovoltaic technologies. Science of silicon pv cells scientific base for solar pv electric power generation is solidstate physics of semiconductors silicon is a popular candidate material for solar pv cells because. It is the sum of the i 2 r losses for each of the resistors plus the losses in each of the diodes. Todd kaiser montana state university solar cell lab manual july 2009 this manual was designed for use with the montana microfabrication facility at montana state university. Sunlight is composed of photons like energy accumulations, or particles of solar energy. Lecture notes fundamentals of photovoltaics mechanical. Solar electric system design, operation and installation an overview for builders in the pacific northwest.
It is a device which converts the light energy into electrical energy. Nph is computed by summing the number of photons in. Many different solar cell technologies are being developed, for various applications. When charged by the sun, this basic unit generates a dc photovoltage of 0. Solar system gk notes in pdf our little corner of the universe is called the solar system. Semiconductors have the capacity to absorb light and to deliver a portion of the energy of the absorbed photons to carriers of electrical current electrons and holes. As the solar radiation is incident at the junction, the junction area is kept much larger for more power generation. Principlethese photo voltaic devices convert the optical radiation into electricity. Since the voltage is too small for most applications, to produce a useful voltage, the cells are connected in series into. Courtesy of the national renewable energy laboratory. Silicon is a popular candidate material for solar pv cells because. Table of contents solar energy 1 energy from the sun 1 early solar energy commercial adaption 3 applications of solar technology 3 architecture and urban planning 4 agriculture and horticulture 4 transport and reconnaissance 5 solar thermal 7. Photovoltaic solar energy opre 6389 lecture note compiled at 18.
Table of contents solar energy 1 energy from the sun 1 early solar energy commercial adaption 3 applications of solar technology 3 architecture and urban planning 4. You can find a few questions on the solar system in many competitive recruitment exams like railways rrb, ssc cgl, sbi po, sbi clerk, ibps clerk, and ibps po. The physics of the solar cell sharif university of. Sep 01, 2011 this introduction to solar cells covers the basics of pn junctions, optical absorption, and iv characteristics. Calculate size of solar panel, no of solar panel and size of inverter for following electrical load electrical load detail. It consist of silicon, germanium pn junction with a glass windows on the top surface layer of ptype, the ptype material is made very thin and wide so that the incident light photon may easily reach to pn junction. When light is allowed to fall on this cell, the cell generates a voltage across its terminals. Parasuraman,department of metallurgy and material science,iit madras. Solar energy notes sunwind solar car kits and solar. F top contact, striking the dye on the surface of the tio 2. The amorphous word with respect to solar cell means that the comprising silicon material of the cell lacks a definite arrangement of atoms in the lattice, noncrystalline structure, or not highly structured.
This introduction to solar cells covers the basics of pn junctions, optical absorption, and iv characteristics. The solar modules or mounts may fall if the installation is not strong enough, for example when parts are not. Today it is a rapidly growing and increasingly important renewable alternative to conventional fossil fuel electricity generation, but compared to other electricity generating technologies, it is a relative newcomer, with the first practical photovoltaic devices demonstrated in the 1950s. Explanatory notes for nrels best research cell efficiencies chart. Sunlight is composed of photons like energy accumulations, or. Stand alone systems, concept of microgrid and its components, hybrid systems hybrid with diesel, with fuel cell, solarwind, wind hydro systems, mode controller, load sharing, system sizing. Introduction to solar cells horizon energy curriculum. Semiconductor materials commonly used to build photovoltaic devices need to have bandgaps that match the solar spectrum. Solar cells absorb some of the photons from sunlight and convert it to a useable amount of direct current electricity. After discussing some basics from electrodynamics in chapter 4 and solar radiation in chapter 5, we spend several.
Since the voltage is too small for most applications, to produce a. Solar cells made of these materials can thus have a thickness clearly below 10. Therefore, asi amorphous solar cell is comparatively cheaper and widely available. Part ii aims to cover all the physical fundamentals that are required for understanding solar cells in general and the different technologies in particular. A solar cell is an electronic device which directly converts sunlight into electricity. Because the earths atmosphere is a spectrally selective filter which modifies the sunlight, the solar energy incident on a cell at the earths surface will be quite different, both spectrally and in magnitude, from that incident solar cells 6. All waves have a certain distance between peaks called the wavelength figure 11. Rohsenow heat and mass transfer laboratory, mit images removed due to restrictions. Special attention is paid to the problems of nonhomogeneous current distribution and the effective series resistance. For this reason it is useful to characterize light radiation by parameters associated with waves. The costs of solar power have been declining steadily and.
Photovoltaics is the process of converting sunlight directly into electricity using solar cells. A solar cell is an example of a photovoltaic device, i. Shading one cell will essentially turn off all the cells in its group. An overview of solar cell technology mike mcgehee materials science and engineering global climate and energy projectglobal climate and energy project center for advanced molecular photovoltaics precourt institute stanford university konarka nanosolar. The internally generated heat in the solar cell is calculated according to the equivalent circuit diagram, shown at the beginning of the reference page, in the solarinduced current section. Solar cells and photodetectors are devices that convert an optical input into current. European commission photovoltaic solar energy development and current research. Solar absorbed light is transferred to the electrons of the pv cell atoms exiting them and producing the electrical current with the help of a builtin electric field which provides the needed voltage. Solar electric system design, operation and installation.
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