As a society, we are looking for lighting solutions that are effective, inexpensive and healthy for the environment. The last decade has seen an explosion in lighting technology. Twenty years ago, incandescent bulbs were the only widely available lighting option. Today, there are various new lighting technologies competing for consumers’ attention. This article compares and contrasts two types of lighting: induction and LED light.
First, it’s helpful to understand why both induction and LED technology are superior to the original incandescent bulb designed by Edison. An incandescent light bulb consists of a vacuum glass envelope, two electrodes connected to an electrical source, and a filament suspended between the electrodes. When electric power is flipped on, the electrodes complete a circuit through a tungsten filament. This filament glows white hot, creating usable light.
Certainly, Edison was a genius for discovering the incandescent light bulb, but there are still a few weaknesses in his design. First, the interior of the bulb must either be a vacuum or filled with an inert gas. If any oxygen enters the bulb, it causes the tungsten filament to evaporate, which in turn breaks the electrical circuit and renders the bulb useless. Another flaw in the Edison light bulb is its inefficiency; 95 percent of the electricity used in an incandescent bulb is lost as heat.
How LED Lights Work
LED technology is much more efficient and much more complicated. LED stands for light emitting diode. Engineers can create diodes by pairing a negatively charged semiconductor with a positively charged semiconductor. A semiconductor is simply any material that can conduct electricity.
On an atomic level, every particle has either a negative or a positive charge. These two charges want to balance each other out – one negative particle plus one positive particle equals an energy neutral situation. The developers of LED technology took advantage of this natural phenomenon by placing a negatively charged “N-type” semiconductor with a positively charged “P-type” semiconductor. When the LED light is turned off, balance is in place – every negative particle has a partnering positive particle.
However, by connecting the N-type material to the negative end of a battery or power circuit and the P-type material to the positive end of a battery or power circuit, engineers can force imbalance between the two semiconductors. As electrons are freed from their partners, they begin to jump to a different energy level (called an orbital in chemistry) and release light. Of course, not all conducive materials will release light in this situation. LED technology gurus have found the right type of materials for creating different colors of light.
How Induction Lighting Works
An induction lamp uses an entirely different approach. Induction bulbs operate on the same principles as fluorescent bulbs. In a fluorescent bulb, a filament connects two diodes that bring an electrical current into a sealed glass envelope. Mercury vapor within the bulb is suspended in an inert gas. As electricity hits the mercury vapor, it becomes excited and emits UV light. A coating of phosphors inside the fluorescent bulb converts UV light into visible light. Different phosphors create different colors of light.
Induction bulbs solve a weakness in fluorescent technology. The tungsten filament is the weakest part of a fluorescent bulb; it can break or become stripped by electrical current. Additionally, the glass envelope around a fluorescent bulb can become leaky, which allows atmospheric gases into the bulb and throws off the balance of inert gasses inside. Induction lamps solve this problem by removing the filament and internal diodes from the equation. Instead of exciting the mercury with a filament, they turn it on with a powerful electromagnet outside of the bulb itself. Once the mercury is excited, it emits UV light that is converted into visible light, just as in a fluorescent bulb.
Given this introduction to the science behind lighting, we are ready to understand the pros and cons of induction and LED technology.
Advantages of LED Lights
- No hazardous materials. An LED light contains no mercury, which is a toxic substance for humans and animals alike.
- Can be used in cold environments.
- Produces no UV light. Over time, UV light can cause damage to products; for instance, under a UV light, plastic becomes yellow and brittle.
- Extremely long lifespan. A single LED bulb may burn for 50,000 hours or more.
- LED lights can be dimmed.
- LED lights can also be directed – their light beams may be focused to provide flood lighting or more laser-like focused lighting.
Disadvantages of LED Lights
- Color matching can be challenging. Many LED lights emit a slightly bluish light, although advancements in technology have alleviated this problem in higher-end flashlights.
- High upfront cost. As LED technology develops, this downside is disappearing.
Advantages of Induction Lighting
- Even longer lifespan than LED lights. Some induction bulbs can last for 100,000 hours.
- More consistency with color matching.
- High efficiency. Induction bulbs are usually more efficient than LED lights.
Disadvantages of Induction Lighting
- Doesn’t operate well in cold conditions. An induction bulb requires time to warm up when operating in cold conditions.
- Hazardous materials mean induction bulbs must be recycled separately. Mercury is an extremely dangerous material.
- They create high amounts of electrical radiation, which may explain why people sometimes complain of headaches after working around an induction bulb.
- Induction bulbs cannot be dimmed.
- Induction light cannot be focused; it can only provide flood lighting.
- Produces UV light that can harm products.