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Want gianormous yields? Cylindrical grow wheels and LED lighting are revolutionizing the way we grow...and grow...and grow! By Diana Campos WHILE LED LIGHTS may not have been successful when they first appeared on the Cannabis cultivation scene — having failed to meet the appropriate intensity requirements needed to sustain plant life — they have certainly grown to be an efficient and effective alternative choice of artificial lighting for gardeners all around the world. Recent improvements to the technology have made it possible for LED grow lights to take some of the trickiest but most rewarding plants to nurture all the way from sprouting to flowering with less of an impact on the environment and on overall running costs than their competition.
SO WHAT EXACTLY IS AN LED AND HOW CAN IT BE USED TO GROW PLANTS? To begin with, LED stands for light emitting diode. These diodes operate by an optical occurrence known as electroluminescence, which is the direct conversion of electric energy into light. On paper, a single LED is structurally simple: two pieces of semiconducting material form a chip which is held together inside of a transparent plastic case by terminal pins. This case is specifically designed to release emitted beams of light through the rounded end at the Left: The Volksgarden.
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top of a bulb — otherwise known as the lens — at different angles. Without this lens, the emission would typically be absorbed back up by the semiconductors. But how exactly does this chip produce light? In order to explain this phenomenon, let’s take a closer look at the materials that make it up: the two bonded semiconductors. One side of the chip is made up of P-type material and the other side is made up of N-type material. The P-type half of the chip contains more positively charged particles due to empty holes within the material, whereas the N-type half has more negatively charged particles. Once bonded, the two materials form a P-N junction in which free electrons (the negatively charged particles) move to fill up the positively charged empty holes. By doing so, the charges cancel out, forming what is known as a depletion zone in the middle of the chip. Without enough voltage, no current is able to flow across this “dead” zone. This is where electricity comes in. When the P-type end of the chip is connected to the positive side of a circuit and the N-type end is connected to the negative side of the same circuit, the depletion zone disappears as holes are emptied of electrons. These electrons are
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