LEDs are a relatively new type of light which were introduced in the 1960s, but really only gained prominence in since the new millennium. Short for light emitting diode, LEDs are a type of semiconductor light source. Rather than using an electrified filament (which can get very hot) like traditional light bulbs do, LEDs cause electrons to release photons, which results in a light called electroluminescence. While early bulbs were dim and available in very few colors, today’s LEDs come in a wide variety of colors and can be quite bright. They also do not emit heat which makes them very safe particularly outdoors or for uses like lighting a pine tree.
Applications for LEDs While individual LEDs are quite small, they can be grouped together to make large, bright fixtures. Many cars today are using LED lights in their tail lights and even head lamps, providing red, orange and white light bright enough to see and be seen. In just the past couple of years LEDs have begun to be used in home lighting. First, they made their way into exterior lights and holiday lights. But today they are appearing as lights inside appliances include refrigerators and microwaves, and even inside light bulbs where multiple LEDs are affixed inside a traditional looking light bulb which can be screwed into any conventional fixture.
Low powered LEDs are a great way to bring attention to an object, for example by illuminating a car’s license plate or a building’s exit sign. Higher powdered LEDs can produce a variety of lighting. They can be suitable for specific situations, like inside a fridge, exterior pathway lighting or even full out task lighting when inside as a group into a fixture or bulb.
One of the great things about LEDs is that they are incredibly long lasting. An LED can last anywhere from 25,000 to 100,000 hours – perhaps more. In fact, many LEDs that were put into use in the 1980s are still shining just as brightly today! This makes them an excellent choice for light bulb replacement in the home, particularly in areas that are hard to reach. For example, an LED placed in a fixture at the peak of a cathedral ceiling or above a staircase will likely never need to be replaced in the entire time that the original installer owns the house. Of course, there is a price to be paid as such LED bulbs currently costs upwards of $25 per bulb, but the price is worth it in longevity and lack of maintenance. In addition to being cost effective, long lasting, bright and safe, LEDs are also very energy efficient.
Energy Efficiency in LEDs Surprisingly, not all LEDs are energy efficient, well, depending upon how you look at it. Every LED uses less energy to run than a traditional light bulb. They also reduce far less heat. However, there is some heat, and a well designed, efficient and safe LED will include a small heat sink to capture and disperse this heat. Also creating white light with an LED presents certain challenges and puts stress on the design. Thus, Energy Star (a governmentally sponsored energy conservation group) has developed a system for rating LEDs.
When you purchase an LED, look for the Energy Star symbol on the package. This will tell you that the light meets a variety of requirements including safety, usefulness and energy efficiency. And Energy Star approved LEDs will meet the following standards: It will turn on instantly, without the delay inherent to some poorly designed LEDs; it will not flicker if dimmed by a dimmer switch or lack of current; it will provide excellent color quality, with a consistent color that stays true and crisp over time; the light will be well distributed and consistently bright over time; and it will be energy efficient, demonstrating the ability to be more efficient than fluorescent lighting and draws no power when in an “off” state.