What is a LASER? Stimulated Emission and Population Inversion

LASER Population Inversion
The word “laser” is an acronym for “light amplification by the stimulated emission of radiation.” Lasers of all kinds consist of several basic components: an active medium, an outside energy source, and an optical cavity with carefully designed mirrors on both ends. One of the mirrors is 100 percent reflective while the other is somewhat less reflective, so a beam can be emitted. The active medium is inside the optical cavity and is excited with an external energy source (typically electricity). For the cavity to emit laser radiation, the active medium has to achieve an unusual energy state called “population inversion.” (more…)

Solar Dryer: Agriculture and Food Drying Systems

Solar dryers are special structures that enhance the drying power of the sun and protect the agricultural product from dust, dirt, and insects. Table below shows a block diagram of an active solar drying system, consisting of solar air collectors, a drying unit or chamber, and an air handling unit. An active solar drying system can accommodate the use of a backup heat source when there in not enough solar heat available. (more…)

Geothermal Power Stations and Non Condensable Gas (NGC)

The total installed geothermal power generating capacity in the world is approximately 9000 MWe from 21 countries, with the United States leading at nearly 3000 MWe and The Philippines with nearly 2000 MWe (Table II). Other major countries are Italy, Mexico, Indonesia, Japan, and New Zealand, with between 400 and 800 MWe each. (more…)

Characteristics Of Repulsive-Force-Based Suspension Systems: Electrodynamic Suspension

In contrast to electromagnetic suspension systems, electrodynamic suspension systems can provide stable suspension without a feedback system. Imagine a magnet held above a moving flat sheet of aluminum or copper. Following Ampere’s law of induction, an electric field is induced in the moving metal surface that causes eddy currents to flow in closed loops near its surface. The eddy currents in turn set up their own magnetic field, whose polarity, in accordance with Lenz’s law, opposes that of the magnet’s field. Consequently, the magnet is repelled from the moving metal surface, countering the force of gravity. If the magnet is pushed down toward the moving metal surface, the induced currents and the resultant repulsive force increase, restoring the equilibrium position automatically. Conversely, if the magnet is moved upward, the levitating force decreases. (more…)

Natural Cooling and Passive Heating System for Energy Efficiency

Several passive heating systems, if provided with proper ventilation, can ensure to provide cooling. Passive heating and cooling for houses can be done in several ways, one of which is called geothermal energy. Passing the water through pipelines via ground can achieve and distribute the heating and cooling all over the house. (more…)

Energy Efficiency — 6 Tips on Saving Lighting

These days we have two main concerns in the world of business and finance. First the greenhouse global warming and second the financial crisis around the globe. We have the opportunity to improve these concerns by “Going Green”. One part of “Going Green” is choosing to upgrade your lighting system to an Energy Efficiency Saving Lighting. The benefits using thousands of qualified lighting products around the house, commercial business and industrial areas: (more…)

Heat-Actuated Heat Pumps | Energy Application of Micro Technology

Heat-actuated heat pumps are cooling systems requiring no electricity for operation. Rather, a heat source is used, avoiding the need for batteries. This consideration is critical for portable applications because on a weight basis, a stored liquid fuel has anywhere from 35 to 300 times the energy content of batteries, depending on the battery technology considered. Thus, although the simple solution of combining an electric motor, a battery package, and a vapor compression refrigerator may sound appealing, it actually suffers a severe volume and weight disadvantage when compared with a heat-actuated system. (more…)