LED lights – an alternative to conventional lights

energy-efficient and rapidly-developing lighting technologies. Quality LED light bulbs last longer, are more durable, and offer comparable or better light quality than other types of lighting. Residential LEDs especially ENERGY STAR rated products use at least 75% less energy, and last 25 times longer, than incandescent lighting.

LED lighting is very different from other lighting sources such as incandescent bulbs and CFLs. Key differences include the following:

• Light Source: LEDs are the size of a fleck of pepper, and a mix of red, green, and blue LEDs is typically used to make white light.

• Direction: LEDs emit light in a specific direction, reducing the need for reflectors and diffusers that can trap light. This feature makes LEDs more efficient for many uses such as recessed downlights and task lighting. With other types of lighting, the light must be reflected to the desired direction and more than half of the light may never leave the fixture.

• Heat: LEDs emit very little heat. In comparison, incandescent bulbs release 90% of their energy as heat and CFLs release about 80% of their energy as heat.

Advantages of LED Lighting

• Energy Efficiency: LED is the most efficient way of illumination and lighting, with an estimated energy efficiency of 80%-90% when compared to traditional lighting and conventional light bulbs. This means that about 80% of the electrical energy is converted to light whereas traditional incandescent light bulbs that operate at 20% energy efficiency only, 80% of the electricity is lost as heat.

• Long Life: The life of a high-power white LED is projected to be from 35,000 to 50,000 hours, compared to 750 to 2,000 hours for an incandescent bulb, 8,000 to 10,000 hours for a compact fluorescent bulb and 20,000 to 30,000 hours for a linear fluorescent bulb. The long operational life time span mentioned above means also that one LED light bulb can save material and production of 25 incandescent light bulbs. A big step towards a greener future.

• Safety: LEDs are much cooler than incandescent lights, reducing the risk of combustion or burnt fingers.

• Environment friendly: Most conventional fluorescent lighting bulbs contain materials like mercury which is dangerous for the environment. LED lights contain no toxic materials or other harmful gasses and thus help in reducing carbon footprint by one third. LED illumination produces little infrared light and close to no UV emissions.

• Design flexibility: Well-designed LED illumination systems can achieve fantastic lighting effects, not only for the eye but also for the mood and the mind. LED mood illumination is already being used in airplanes, classrooms and many more locations and we can expect to see a lot more LED mood illumination in our daily lives within the next few years.

• Low Voltage: A low voltage power supply is sufficient for LED illumination. This makes it easy to use LED lighting also in outdoor settings, by connecting an external solar-energy source and is a big advantage when it comes to using LED technology in remote or rural areas.

Disadvantages of LED Lighting

• High cost: LEDs are currently more expensive than conventional lighting sources. However, the high initial cost of LED-based systems is offset by lower energy consumption, lower maintenance costs and other factors.

• Temperature dependence: LED performance largely depends on the ambient temperature of the operating environment. Driving the LED hard in high ambient temperatures may result in overheating of the LED package, eventually leading to device failure.

• Light quality:Most cool-white LEDs have spectra that differ significantly from a black body radiator like the sun or an incandescent light. The spike at 460 nm and dip at 500 nm can cause the color of objects to be perceived differently under cool-white LED illumination than sunlight or incandescent sources, due to metamerism, red surfaces being rendered particularly badly by typical phosphor-based cool-white LEDs. However, the color-rendering properties of common fluorescent lamps are often inferior to what is now available in state-of-art white LEDs.

• Impact on insects: LEDs are much more attractive to insects than sodium-vapor lights, so much so that there has been speculative concern about the possibility of disruption to food webs.

With performance improvements and dropping prices, LED lamps can replace 40, 60, and even 75 Watt incandescent bulbs. It’s important to read the Lighting Facts Label to make sure the product is the right brightness and color for the intended location. When chosen carefully, LED replacement products can be an excellent option.