Solar Panels

Solar Panels

Introduction

Solar energy is abundant and inexhaustible, but in the United States less than one-tenth of 1 percent of the nation's electricity supply is obtained from solar energy. In all other large economies, whether they are located in regions of abundant direct sunlight or in regions with intermittent direct sunlight, the situation is similar: Solar power makes a very small contribution to the energy mix. To understand the challenges involved in using solar energy, it is necessary to understand the resource in some detail. This entry begins with a description of the characteristics of sunlight.

When sunlight is intercepted on Earth's surface (rather than in space), the characteristics of Earth's surface and its atmosphere become extremely important. Earth's surface is curved, and Earth rotates rapidly. Consequently, the amount of sunlight striking a flat plate placed parallel to the surface varies enormously from one location to the next and from one hour to the next. Understanding local conditions contributes to an appreciation of why solar energy has been so difficult to harness. This entry concludes with a description of some of the ways that the geometry of Earth and the properties of Earth's atmosphere complicate the harnessing of solar energy.

Discussion

The solar panels are constituted by hundreds of these cells, which wirings voltages sufficient to adequately provide for example a battery recharge. They are useful in many fields, from the domestic to the satellite artificial. When light energy strikes the cell barrier, there is a detachment of electrons from the atoms begin to move freely within the material. If you measure the voltage between both ends of the material (positive and negative) will observe that there is a difference in potential between 0.5 and 0.6 volts.

If we apply an electric charge, we see that it is possible to obtain a current of 28 milliamperes per square centimeter lit. We have converted the device into a kind of battery that will remain indefinitely in both providing energy received enlightenment. But this small amount of energy is inadequate and useless, if we are not able to get higher voltages and currents that allow practical applications. To this end are designed in each wafer hundred diodes, which are interconnected in series and parallel are capable of delivering voltages of several volts and currents of the order of amperes.

This basic system of power generation by means of sunlight can obtain a higher yield if devices are arranged Control suitable. Subsequently, the obtained energy must be stored so it can be used at night, in the absence of light cannot directly obtain. Solar panels can be coupled in a modular fashion; it allows them to move from a domestic power generation to a more powerful industries or installations of high consumption.

The disadvantages of this system of power generation, not so much the source of that energy, the Sun, which exceeds our needs, nor the raw material from which silicon is extracted, consisting of abundant common sand on our beaches, is technique is the construction of the wafers, overly ...