LED Advantages and Disadvantages




The ultra energy-saving   light emitting diode (LED) light bulb   has taken the home and commercial lighting industry by surprising storm during the past ten years.  Resembling a traditional incandescent bulb, this “solid state” bulb is roughly 90 percent more efficient than its hot filament ancestor, runs much cooler, lasts fifty to a hundred times longer, yet only costs about ten times more.  Whether in home lighting, outdoor flood or spot lighting applications, the LED advantages clearly outweigh the incandescent predecessors markedly.

Prices are dropping every week too, as popularity grows.  It fits in most standard incandescent light fixtures, but because it operates at much lower temperatures, higher brightness LED bulbs can safely be installed in fixtures and enclosed spaces, where excessive heat production has been of concern traditionally.  However, always observe any installation restrictions printed on the bulb’s carton.  Generally though, you can safely run a 100-watt equivalent LED lamp in a fixture that specifies a maximum of 60 watts incandescent with little worry about it overheating.  The CREE LED bulb pictured next produces the same amount of light (lumens) as a 100-watt incandescent lamp, but only draws eighteen watts of power.  Much more of the LED bulb’s energy consumption produces actual light, and far less of it generates heat; thus, brighter LED bulbs can function where the same brightness incandescent bulbs would damage delicate fixture contacts and wiring.

 

Picture of a CREE LED Light Bulb, 100 Watt, the Front of its original carton.
CREE LED Light Bulb 100W, Carton Front

LED lights can survive far greater physical shock than either incandescent or compact fluorescent bulbs, and typically require less space than CFLs.  LED bulbs typically require no electronic ballasts, which increases their overall efficiency and reduces EMI (electromagnetic interference) and RFI (radio frequency interference) that typical fluorescent fixtures generate.  Further the absence of the ballast generally means that LED light bulbs work well with incandescent light dimmers, to provide a full range of brightness variance.  They’ll dim down to practically no light output, without flickering, buzzing, or clicking.  Finally, getting rid of the electronic circuitry of a solid state ballast further immunizes the LED light bulb from power surges and spikes.  With less components to fail in the LED circuitry, longer life becomes a virtual certainty.

The overall performance and affordability (increasingly lower costs) of LED bulbs has improved so much since 2010, that manufacture of traditional household incandescent lamps has now ceased here in the U.S.  While they’re still made for specialized applications, the standard tungsten filament-based bulb is no longer produced for wide-scale consumption.  As of this writing, stores still sell these, but only until existing reserves are used up.

 

Picture of a CREE LED Light Bulb, 100 Watt, back of original carton.
CREE LED Light Bulb100 Watt, Carton Back.

LED Advantages, Benefits, Pros, and Features

  • LEDs save much energy.  This 80 to 90 percent less power consumption than incandescent bulbs makes LED bulbs a blessing for aging and under-rated power grids worldwide.  By reducing energy consumption by this high extent, we can avoid (or at least delay) costly upgrades to city power distribution circuits.  These savings can also reduce dependence on foreign oil and overly rapid depletion of domestic natural resources.
  • Increased reliability.  LED light bulbs have come a long way in recent years.  The fail less often, last longer, emit a more solid, flicker-free, full spectrum light, and more of them last as long as or in many cases, longer, than advertised.  They hold up better than incandescent lamps and compact fluorescents when frequently switched on and off.
  • Product less heat.  Since more of the energy drawn is converted into visible light, less is transmuted into wasteful heat. This can lower air-conditioning costs in establishments and homes that replace many incandescent and CFL bulbs with LED units.
  • Silent operation.  LED lamps demonstrate virtually noise free lighting.  Even when fed from a light dimmer, buzzing, ringing, or whistling of any kind is virtually unheard of.
  • Produce less EMI and RFI.  The 120 volt LED bulb units feature a series string of individual LED lamps.  By connecting them in series, the total input voltage required to light these lamps to full brightness increases as more lamps are added.  Choose the right lamp count, and you get an integrated unit that operates directly from the 120 volt line; requiring no electrical conditioning except for perhaps, the conversion from AC to DC.  Components to accomplish this are simple to arrange, and no switch mode power supply drivers are needed.  Thus, less to no electromagnetic and radio frequency interference is generated during normal operation.
  • LED bulbs are getting cheaper.  As the LED production technology matures, prices are falling, and you can now buy packs of two bulbs for significantly lower prices than if you bought each lamp separately.
  • LEDs provide MUCH longer bulb life.  Though some LEDs fail before reaching life expectancy, as has happened to us once or twice in recent years, in theory, they should outlast incandescent bulbs by several to as much as fifteen times if properly cared for.  They probably will last longer without being so delicate, once manufacturers make more robust the ballast circuitry. The CREE bulb pictured above comes with a ten year limited warranty.  We’ve run the 60-watt version as a bathroom night light, nonstop, for nearly four years now, and it’s still going strong, and glowing as brightly as it did when first purchased.
  • Wide color choices with LEDs.  Unlike incandescent bulbs, LED lamps are available in several colors such as the 2700k (warm white), 3000 K (less warm white), 5000 K (cool white), and 6500 K (daylight white, which is a sky-blue shade of white).  Manufacturers attempted this with incandescent lamps but never got the colors above 3000 K or so, to work well.  Efficiency and life span of incandescent bulbs drop as you move their color output more toward blue.  CFLs are highly efficient however, regardless of color temperature output.
  • LEDs fit same lamp fixtures as incandescent and CFL light bulbs.  You needn’t replace your standard light fixtures and lamps to take advantage of  LEDs.   With almost non existent heat output, LED lights can generally be used any place designed for a regular incandescent bulb, so long as the LED bulb itself physically fits into that space.
  • Instant, full brightness. Whether hot or cold climates, LED lamps illuminate to full brightness instantly upon energizing.  No warm up time required, and they provide steady, fluctuation free lighting.  Usually no flickering.  If you do observe flicker, you may be running a dimmer on a non dimmable LED light.  Also, flickering is a sign that the bulb itself may be burning out.
  • Less temperature sensitive.  LEDs emit the same amount of light for a given voltage, over a wide range of temperatures.
  • Less long-term brightness reduction. While tungsten deposits accumulate on the inner walls of incandescent lamps over many hours of operation, and cause notable reductions in light output, LED light bulbs suffer far fewer of these difficulties.  Typically, they burn nearly as brightly at the end of their lives as at the beginning, although some solarization and other deteriorations of the plastic housing and reflective surfaces may cause noticeable dimming and color changes over time.
  • Long extinguishing time.  Today’s LEDs feature an interior phosphor that continues emitting usable light for a few milliseconds after power has been switched off.  Then, the output dims down that same way and incandescent bulb does as its filament cools off once turned off.  This helps further solidify the outputted light by guarding against AC flicker that it so often seen in those old technology fluorescent lamps.
  • Physically and electronically more rugged.  No delicate glass tubes to break.  These state of the art bulbs are typically constructed of thick metals and hard plastics, that resist shattering.  Also, with less supporting electronics in the 120 volt varieties, LED bulbs tend to fail less frequently than CFLs or incandescents.
  • More Environmentally Safe.  Since LEDs should be recycled, and since appropriate recycling stations have not yet been set up in many market areas, the consumer must store them until such facilities become available.  Fortunately however, since LED bulbs contain no hazardous gasses, and since they’re difficult to break accidently, long term storage until neighborhood recycling becomes widely available should pose few if any problems.
  • Improving technology over all.  Over time, efficiencies in LEDs have risen, in terms of energy consumption as well as initial purchases prices.  Indications are that this trend will continue for the foreseeable future.  So obsolescence should not occur for at least a decade, and probably more.

 

Picture of an LED Lamp, 60 Watt Equivalent, Cool White 5000 K, Glowing at full brightness.
LED Lamp, 60 Watt Equivalent, Cool White 5000 K, Glowing at full brightness.

LED Disadvantages, Cons, Problems, and Concerns

  • Among the most expensive home lighting solution.  LED bulbs are currently priced at the high end of affordability in home lighting markets.  However, we expect this condition to be quite temporary.  As with other popular technologies, the growing widespread use of LED light bulbs in homes and offices, will quickly drive down prices.
  • Heavy compared to CFls and incandescent lamps.  Most LED bulbs incorporate an integrated metal heat sink, as shown in the picture of the glowing LED light above.  This makes them heavier than similarly sized filament and CFL lamps. This added weight, adds to the overall expense of the bulb (shipping costs increase).
  • LEDs should not be thrown in the trash.  You can’t just throw away burned-out LED bulbs, as they are considered hazardous waste due to the printed circuit boards and solder that many contain.  However, as solid state lighting such as LEDs moves into the main stream markets, recycling stations and services are being set up nationwide for proper disposal.

Thus, considering all of this, our energy-savings strategy has, and will continue to incorporate SOME CFLs around the apartment.  But we will not replace ALL of them with LEDs until the cost per LED bulb drops a bit more. Then,  upgrades of all lights to LEDs will be completed, with much excitement.

 

References

 

Revision History

  • 2017-01-19: Adjusted tags, and simplified the title to: LED Advantages and Disadvantages
  • 2016-01-05: Added more appropriate tags.
  • 2015-09-27: Added appropriate tags.
  • 2015-07-06: Originally published.