Are LEDs cost-effective?
Costs of LED lighting products vary widely. Good quality LED products currently carry a significant cost premium compared to standard lighting technologies. However, costs are declining rapidly. In 2001, the cost of white light LED devices was more than $200 per thousand lumens (kilo-lumens). In 2007, average prices have dropped to around $30/klm. It is important to compare total lamp replacement, electricity, and maintenance costs over the expected life of the LED product.
Are LEDs energy-efficient?
The best white LED products can meet or exceed the efficiency of compact fluorescent lamps (CFLs). The best warm white LEDs available today can produce about 45-50 lumens per watt (lm/W). In comparison, incandescent lamps typically produce 12-15 lm/W. Good LED system and luminaire design is imperative to energy-efficient LED lighting fixtures.
How long do LEDs last?
Unlike other light sources, LEDs usually don’t “burn out;” instead, they get progressively dimmer over time. LED useful life is based on the number of operating hours until the LED is emitting 70% of its initial light output. Good quality white LEDs in well-designed fixtures are expected to have a useful life of 30,000 to 50,000 hours. A typical incandescent lamp lasts about 1,000 hours; a comparable CFL lasts 8,000 to 10,000 hours.
What other LED features might be important?
Depending on the application, other unique LED characteristics should be considered:
- Directional light
- Low profile/compact size
- Breakage and vibration resistance
- Improved performance in cold temperatures
- Life unaffected by rapid cycling
- Instant on/no warm up time
- Dimming and color controls
- No IR or UV emissions