Fluorescent Light Bulbs Facts
Energy-saving bulbs continues to make inroads into the mainstream market. A recent example is the Pali Momi Medical Center in Hawaii. This system has replaced more than about 2300 fluorescent lamps and compact fluorescent lamps with LED technology, which limits their utility bills over 50%!
While LED lamps have an initial cost estimate much larger than compact fluorescent lamps, makes their lives for them. LEDs can last up to 100,000 hours, compared to compact fluorescent lamps, which can last10000-15000 hours. The higher cost is usually paid in the first year of use, from year to year in a row as a pure savings. A spokesman for the Pali Momi Medical Center expects its investments in LED savings in about 15 months to be repaid with the savings continue for years to come.
Substantial savings to the airport in Honolulu was seen, where large-scale retrofit of parking structure lighting saves $100,000 a month in electricity. When you have performed updates similar to other airport facilities, the savings would be incredible. LED lights not only save a lot of money in the long run, but they are better for the environment than CFLs. Energy efficient light bulbs contain mercury and emit UV light, while LEDs do not contain toxic chemicals, and UV damage.
Airports are not the only places that can benefit from the LED lamps. Each business or government is saving huge amounts of money by replacing incandescent bulbs with these energy efficient lighting solutions. Besides saving money and electricity, switching to LEDs is a good way to go green.
LED Bulbs: The Future Of Lighting
Article by David Fessler
December 7, 2011
Like worn out rechargeable batteries, CFLs contain hazardous chemicals (in their case, a small amount of Mercury) and must be disposed of properly. Setting up that recycling infrastructure will probably happen at the store level. But the average consumer will just throw them in the trash.
LEDs are really the future of lighting. Many Christmas lights are already LED-based, and commercial lighting is heading in that direction and will drive costs down at the retail level.
When I checked on the price for a 100-watt equivalent LED bulb the other day at Home Depot, it was around $26. That’s steep, but still represents significant savings over the lifetime of the bulb. Prices will continue to drop though, and I expect we’ll see prices in the $4 to $5 range in just a couple of years.
Written by John Kowalski of Green Ray LED.
Comparing the lumen output of LEDs to a discharge source is not an accurate way of measuring effective light output of a Luminaire. HID lamp lumens are measured spherically, counting all the lumens being produced over 360 degrees. The discharge arc tube is NOT a point source and is difficult to optimize optically, making for poor light collection efficiency and utilization. Many light fixtures have to redirect most of the lumens produced by a bulb, losing as much as 50% of the output.
LEDs on the other hand are directional and have practically no wasted lumens. Virtually every LED lumen is directed and placed to maximize efficiency. A more accurate evaluation is to measure actual foot-candles or LUX on the ground. In addition, HPS and MH lamps have a considerable initial light output loss within the first 6 months. LEDs have no such drop and deliver useful light [with only 30% depreciation] for 12 to 15 years before needing replacement.
Photopic lumens’ refers to the amount of light emitted from a light source as measured by a light meter. The typical light meter is most sensitive to the yellow-green part of the color band. This is the light that is seen by the cone receptors in the eye, the eye’s cone activated or photopic vision.
However, the rod receptors in the eye also receive light, called rod activated or scotopic vision. This light, which is rich in the blue portion of the spectrum, isn’t measured by the typical light meter. Therefore, until now, lighting manufacturers have only measured light output based on the eye’s sensitivity to one type of vision (photopic). A true evaluation of lumen effectiveness comes from the combination of the light received by the rods and cones (photopic and scotopic); or ‘seeable lumens.’ Therefore, measuring only photopic lumens is misleading when comparing different colors of light. This is why even though a lower lumen reading is obtained with a LED vs. HPS or Metal Halide; the LED will produce more seeable light.