Photon flux is crucial in determining the generation rate of solar cells. The energy of photon at a particular wavelength multiplied by the photon flux will yield the power density which is measured in Watts per m2 (W/m2). The power density at a particular wavelength is characterized by the spectral irradiance which is the most commonly used method to characterize a light source. These set of equations are crucial in selecting materials for designing solar cells so that we can effectively utilize the energy radiated by the Sun into the Earth’s
Nuclear power seems to be an answer for global warming, but concerns about terrorist attacks on Earth bound nuclear power plants have intensified environmentalist opposition to nuclear power. Earth based solar panels receives only a part of the solar energy. So it is desirable to place the solar panel in the space itself, where, the solar energy is collected and converted in to electricity which is then converted to a highly directed microwave beam for transmission. This microwave beam, which can be directed to any desired location on Earth surface, can be collected and then converted back to electricity. This concept is more advantageous than conventional methods.
Note that ηo represents the fraction of the solar radiation absorbed by the plate and depends mainly on transmittance of the transparent covers and on the absorbance of the plate . The energy loss coefficient includes the losses by the upper cover, the laterals, and the bottom of the collector. The upper cover losses prevail over the others, depending to a large extent on the temperature and emissivity of the absorbent bed, and besides, on the convective effect of the wind on the upper cover. The thermal efficiency of the solar collectors (ηI) is defined as the ratio between the energy gain and the solar radiation incident on the collector plane [6,7,8]: ηI=(ṁCp (Tout - Tin ))/IAC ……….. (7) Exergy analysis: This article focuses on the combination of the two laws of thermodynamics, which are described in the concept of exergy analysis. The assumptions made in the analysis presented in this study are [6,7,8,9]: (i) steady state, steady flow operation, (ii) negligible potential and kinetic energy effects and no chemical or nuclear reactions, (iii) air is an ideal gas with a constant specific heat, and its humidity content is
This planet is named after the messenger of the Roman gods, known as Hermes in Greek mythology. This is because of the speed in which Mercury orbits the Sun and the speed with which Mercury the Roman deity was able to deliver messages. This planet has just 38% of the gravity on Earth and so it isn’t able to hold the atmosphere it has, instead it gets blown away by solar winds thus it has a very thin atmosphere. However the same solar winds bring new gases, radioactive decay and dust which helps to replenish the atmosphere. Due to its low of gravity and lack of atmosphere, Mercury has no moons or rings.
PV cells are basically made up of a PN junction fabricated in a thin wafer or layer of semiconductor (usually silicon). To understand the electronic behavior of a solar cell, it is useful to create a model which is electrically equivalent, and is based on discrete electrical components whose behavior is well known. An ideal solar cell may be modeled by a current source in parallel with a diode; in practice no solar cell is ideal, so a shunt resistance (RSH) and a series resistance (RS) component are added to the model. The resulting equivalent circuit and the schematic representation of a solar cell are shown in figure 3.1
The term parallax is derived from the Greek term “parallelism” which means the ability to change. Parallax defines the displacement of stationary objects when viewed from different positions. Friedrich Wilhelm Bessel (1784 –1846) , a German astronomer and mathematician, was the first person to calculate the distance from the sun to another star in space. Alfa is parallax angle, of which stars B & C are seen to make from star A. The angle Alfa is variable due to rotation of the earth around the sun.
CHAPTER 3: SOLAR PHOTOVOLTAIC ENERGY CONVERSION 3.1 Introduction to Solar Energy Solar energy is gets by the radiation of the sun. Solar energy is available on the earth continuously and in abundant manner. Solar energy is freely available in the nature. It doesn’t produce any gases and it is pollution free. It is free of cost and has low maintenance cost.
What is Mars? Mars is the fourth planet away from the sun. It has a surface area of 144.8 million km2, while Earth’s surface area is 510.1 million km2. A day on Mars is 24 hours and 37 minutes meaning that its only 37 minutes longer than on Earth. If we decide to colonise, it wouldn 't be that difficult to adjust to the day length.
Solar energy is quite humbly the energy created directly by the sun and collected in a different place, typically the Earth. The sun creates its energy through a thermonuclear process that converts about 650,000,000 tons to hydrogen to helium every second. The process creates temperature and electromagnetic pollution. (Dmguion, 2011) The heat remains in the sun and is